I seem to recall someone (or more than one ...) here is/was involved in
building tube frames for race cars . I'm debating building a trike rear end
to put on an older Honda CB750 , and need a bit of guidance ... my wife
wants to ride but doesn't like to lean .
Looks like the best-handling option is going to be unequal length A-frames
with CV jointed half shafts and dual inboard disc brakes . I'm undecided
about springing options , whether coil-over shocks , maybe a single
transverse leaf . Either option will require a torsion bar to control body
roll . Going to have to have an enclosed spider differential setup , with a
sprocket mounted for chain drive - maybe from an ATV ? Front suspension hubs
from a FWD car look like the cheapest option ...
And it all needs to fit into a 14 x 14 x 27 inch package , plus the width
of the A-frames , and the mounting points extending to the front to bolt it
to the M/C frame . I'm considering using 1" sq tube and 1x2" tube for the
frame members . I'd like to use the original swingarm and shock absorber
mount points , since they're designed to support the loads ... and I
haven'rt even begun to consider body work to cover it all .
--
Snag
Wannabe Machinist

On Sun, 3 Oct 2010 08:06:22 -0500, "Snag"
wrote:

I seem to recall someone (or more than one ...) here is/was involved in
building tube frames for race cars . I'm debating building a trike rear end
to put on an older Honda CB750 , and need a bit of guidance ... my wife
wants to ride but doesn't like to lean .
Looks like the best-handling option is going to be unequal length A-frames
with CV jointed half shafts and dual inboard disc brakes . I'm undecided
about springing options , whether coil-over shocks , maybe a single
transverse leaf . Either option will require a torsion bar to control body
roll . Going to have to have an enclosed spider differential setup , with a
sprocket mounted for chain drive - maybe from an ATV ? Front suspension hubs
from a FWD car look like the cheapest option ...
And it all needs to fit into a 14 x 14 x 27 inch package , plus the width
of the A-frames , and the mounting points extending to the front to bolt it
to the M/C frame . I'm considering using 1" sq tube and 1x2" tube for the
frame members . I'd like to use the original swingarm and shock absorber
mount points , since they're designed to support the loads ... and I
haven'rt even begun to consider body work to cover it all .


There's a manufacturer for trike conversions right in my hometown.
They are a major supplier for the entire country. My son has even
sub-contracted for them. I bet "the kid" could get you a kit for
wholesale if you're interested in that route. He'd want to make a
couple $ for his trouble.

Karl

Karl Townsend wrote:
On Sun, 3 Oct 2010 08:06:22 -0500, "Snag"
wrote:

I seem to recall someone (or more than one ...) here is/was
involved in building tube frames for race cars . I'm debating
building a trike rear end to put on an older Honda CB750 , and need
a bit of guidance ... my wife wants to ride but doesn't like to lean
.
Looks like the best-handling option is going to be unequal length
A-frames with CV jointed half shafts and dual inboard disc brakes .
I'm undecided about springing options , whether coil-over shocks ,
maybe a single transverse leaf . Either option will require a
torsion bar to control body roll . Going to have to have an
enclosed spider differential setup , with a sprocket mounted for
chain drive - maybe from an ATV ? Front suspension hubs from a FWD
car look like the cheapest option ... And it all needs to fit into
a 14 x 14 x 27 inch package , plus the width of the A-frames , and
the mounting points extending to the front to bolt it to the M/C
frame . I'm considering using 1" sq tube and 1x2" tube for the frame
members . I'd like to use the original swingarm and shock absorber
mount points , since they're designed to support the loads ... and I
haven'rt even begun to consider body work to cover it all .


There's a manufacturer for trike conversions right in my hometown.
They are a major supplier for the entire country. My son has even
sub-contracted for them. I bet "the kid" could get you a kit for
wholesale if you're interested in that route. He'd want to make a
couple $ for his trouble.

Karl

I'd settle for a set of sketches of the geometry ... the budget on this
one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that hot on
leaning into turns , and my budget is whatever I can get for it . Probably
somewhere in the $700-$900 range - which will buy the materials (I hope !) .
--
Snag
Wannabe Machinist

On Sun, 3 Oct 2010 08:06:22 -0500
"Snag" wrote:

snip
I'm debating building a trike rear end
to put on an older Honda CB750...

Have you considered a trike front end? In my eyes this would be a
simpler task. I think it was Wes who took a picture of one several years
ago. It was an older motorcycle, like a 750. He might still have the
picture around somewhere. Pretty sure I saved it too, but where on the
hard drive is the question I'll go searching for it (picture) if you
want to pursue this idea.

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

Leon Fisk wrote:
On Sun, 3 Oct 2010 08:06:22 -0500
"Snag" wrote:

snip
I'm debating building a trike rear end
to put on an older Honda CB750...

Have you considered a trike front end? In my eyes this would be a
simpler task. I think it was Wes who took a picture of one several
years ago. It was an older motorcycle, like a 750. He might still
have the picture around somewhere. Pretty sure I saved it too, but
where on the hard drive is the question I'll go searching for it
(picture) if you want to pursue this idea.

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

I'm assuming you mean two wheels up front and single rear drive wheel ?
There's a fairly new production unit , the Trans-Am Spyder with that setup .
I've heard that setup handles better than the two-in-the-rear trikes , but
they still look funny to me ... however , that is a consideration , and I
might just have to drag her out the the Spyder dealer here to see what she
thinks .
It would be a lot easier that way , without drive components complicating
things . If you can find that snapshot I'd appreciate it ! My reply-to is
good ...
--
Snag
Wannabe Machinist

On Sun, 3 Oct 2010 16:24:23 -0400, Leon Fisk
wrote:

On Sun, 3 Oct 2010 08:06:22 -0500
"Snag" wrote:

snip
I'm debating building a trike rear end
to put on an older Honda CB750...

Have you considered a trike front end? In my eyes this would be a
simpler task. I think it was Wes who took a picture of one several years
ago. It was an older motorcycle, like a 750. He might still have the
picture around somewhere. Pretty sure I saved it too, but where on the
hard drive is the question I'll go searching for it (picture) if you
want to pursue this idea.
A WHOLE LOT more surefooted in the handling department. Think Morgan
vs Reliant Robin.

On 10/03/2010 04:00 PM, Snag wrote:
Leon Fisk wrote:
On Sun, 3 Oct 2010 08:06:22 -0500
wrote:

snip
I'm debating building a trike rear end
to put on an older Honda CB750...

Have you considered a trike front end? In my eyes this would be a
simpler task. I think it was Wes who took a picture of one several
years ago. It was an older motorcycle, like a 750. He might still
have the picture around somewhere. Pretty sure I saved it too, but
where on the hard drive is the question I'll go searching for it
(picture) if you want to pursue this idea.

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

I'm assuming you mean two wheels up front and single rear drive wheel ?
There's a fairly new production unit , the Trans-Am Spyder with that setup .
I've heard that setup handles better than the two-in-the-rear trikes , but
they still look funny to me ... however , that is a consideration , and I
might just have to drag her out the the Spyder dealer here to see what she
thinks .
It would be a lot easier that way , without drive components complicating
things . If you can find that snapshot I'd appreciate it ! My reply-to is
good ...

My understanding is that two in front is much more stable than two in
back. The Morgan Trike and it's brethren were winning car races back in
the late '20's, until they were outlawed for not having enough wheels.

With two in back, she'll love you until she finds herself under a
motorcycle. You don't want that.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html

I'd settle for a set of sketches of the geometry ... the budget on this
one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that hot on
leaning into turns , and my budget is whatever I can get for it . Probably
somewhere in the $700-$900 range - which will buy the materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the Honda
750, its chain drive) Then take the smallest rear wheel drive car you
can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would be a
nightmare to design.

Karl

Karl Townsend wrote:
I'd settle for a set of sketches of the geometry ... the budget on
this one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get for
it . Probably somewhere in the $700-$900 range - which will buy the
materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the Honda
750, its chain drive) Then take the smallest rear wheel drive car you
can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would be a
nightmare to design.

Karl

Well , the thing is that I already have the CB750 , and it's paid for .
Got some ideas for casting a housing for the diff out of aluminum I have on
hand ... start with a lost-foam casting , or maybe make a wood pattern that
I can alter for offset depth to accomodate the sprocket , since it's
off-center . Might be able to incorporate a single 4-pot caliper on the diff
housing , that'd simplify things a lot too .
Ideas , ideas , streaming thru my head ... I had a hard time getting to
sleep last night .
--
Snag
Wannabe Machinist

Tim Wescott wrote:


My understanding is that two in front is much more stable than two in
back. The Morgan Trike and it's brethren were winning car races back
in the late '20's, until they were outlawed for not having enough
wheels.
With two in back, she'll love you until she finds herself under a
motorcycle. You don't want that.

--

Tim Wescott

You're right about that !!

--
Snag
Wannabe Machinist

On 10/3/2010 3:24 PM, Leon Fisk wrote:
On Sun, 3 Oct 2010 08:06:22 -0500
wrote:

snip
I'm debating building a trike rear end
to put on an older Honda CB750...

Have you considered a trike front end? In my eyes this would be a
simpler task. I think it was Wes who took a picture of one several years
ago. It was an older motorcycle, like a 750. He might still have the
picture around somewhere. Pretty sure I saved it too, but where on the
hard drive is the question I'll go searching for it (picture) if you
want to pursue this idea.


I like those things a lot. Bombardier makes one most like what you would
want:

http://spyder.brp.com/en-US/

I saw a new one yesterday at the TX state fair. T-Rex

http://www.gizmag.com/go/3535/picture/7357/



--
I can see November from my front porch

On Oct 4, 8:00*am, "Snag" wrote:
Karl Townsend wrote:
*I'd settle for a set of sketches of the geometry ... the budget on
this one is "do it yourself or you can't afford it" .
*We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get for
it . Probably somewhere in the $700-$900 range - which will buy the
materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the Honda
750, its chain drive) Then take the smallest *rear wheel drive car you
can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would be a
nightmare to design.

Karl

* Well , the thing is that I already have the CB750 , and it's paid for

Cross-Slide wrote:
On Oct 4, 8:00 am, "Snag" wrote:
Karl Townsend wrote:
I'd settle for a set of sketches of the geometry ... the budget on
this one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get for
it . Probably somewhere in the $700-$900 range - which will buy the
materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the Honda
750, its chain drive) Then take the smallest rear wheel drive car
you can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would be a
nightmare to design.

Karl

Well , the thing is that I already have the CB750 , and it's paid
for .
Got some ideas for casting a housing for the diff out of aluminum I
have on hand ... start with a lost-foam casting , or maybe make a
wood pattern that I can alter for offset depth to accomodate the
sprocket , since it's off-center . Might be able to incorporate a
single 4-pot caliper on the diff housing , that'd simplify things a
lot too .
Ideas , ideas , streaming thru my head ... I had a hard time getting
to sleep last night .
--
Snag
Wannabe Machinist

Pay close attention to the "Roll Center" of you suspension.
It is what made the Beetle, and the Corvair so "Exciting" to drive.

With a four bar linkage, the links point off into space to the
"reaction point" that imaginary point where the linkages intersect off
in space. THAT is the (instantaneous) point where the wheel pivots
around as it moves up and down.
As the wheel moves up and down that point in space moves too.

You can draw a line from the point of contact on the road to that
instantaneous center and where it crosses above or below you center of
mass is the Roll Center.
If the Roll center gets too high, it tries to jack up that corner of
the vehicle, and tuck that tire underneath. That is wha the Beetles
and Corvair did in a hard corner.

They basically swiveled the rear axle shaft from a single U-joint on
the trans-axle, and that became the Roll center.

If you look at a Corvette or a Jaguar independent suspension, they
have two u-joints and the roll centers are established by the
linkages. The instantaneous center can be anywhere, as set by the
geometry of the linkages.

A Front wheel drive will typically use McPherson struts with a single
lower A arm. That might not be acceptable for your layout. So, finding
the appropriate uprights will be one of the many tricks, or problems
to solve.

Another consideration will be camber gain/loss as the suspension
travels.
And any amount of bump steer. (!)
If on the front of a vehicle, a wheel hits a bump, and that for
example causes that wheel to turn towards the center line, the car
will react as if it is going into a turn, And exaggerate the bump, and
exaggerate the unintended turn, etc.
The vehicle will dart about on a bumpy road.
For example, the right front tire turns so very slightly to the left
as it hits a bump, and visa-versa. The vehicle will dart and skitter
over bumps or ripples. If the wheel bump steers in the other direction
it will be more stable.
This is also important in the back of the vehicle.

There is also anti-dive built into suspension. The brake reaction
torque on the front end will try to make it rise slightly, to overcome
the tendency to nose-dive on braking. This is a function of the front
end A-Arm geometry.
This also affects the rear end.

I don't have enough life expectancy to spend it re-typing several
entire books here.
But there are some important considerations. It is not too complicated
once you understand the principles.

It is no more complicated than understanding gear ratios before you
set out to design or build a transmission from a stack of totally
random gears. You would need to understand ratios, ratio spreads and
other stuff to make it work. But you at least have to know something
about it before you started to make it work "acceptably" the first
time.

Getting a suspension system nearly correct might be perfectly fine
until you hit that first pothole with the wrong wheel while going
around a corner, with just a little mist on the road.......

This might a good place to start.
http://www.carrollsmith.com/books/

I hit a website Sat. night that explained all this you've said in great
detail . And that's the reason I choose to use an unequal length a-frame
type of suspension . I can build in the proper camber characteristics , set
the drive components so there's no "zero movement" in the CV joints , and of
course set it up so the instantaneous roll center stays close to or below
the center of mass . I'm still studying , and will not cut the first chunk
of steel until I'm satisfied that my design will do what I intend it to do .
The woman I love will be ridin' this thing , should it ever come to more
than just talk . And you can bet your sweet a$$ I'm going to make sure she's
as safe as I can possibly make her .
My first car was a '62 Pontiac Tempest , used that infamous Corvair
transaxle that Ralphie got in such a tizzy over . You're right , it was
unsafe under certain conditions . But it left the coolest burnouts ...
( )
--
Snag
Wannabe Machinist

On Sun, 3 Oct 2010 18:00:03 -0500
"Snag" wrote:

snip
It would be a lot easier that way , without drive components complicating
things . If you can find that snapshot I'd appreciate it ! My reply-to is
good ...

It took some digging...

This is the web page that Wes made:

http://garage-machinist.com/BuckleyOldeEngineShow/2008/

Take a look at the first four pictures. Not quite how I remembered it
but maybe it will give you some ideas...

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

Leon Fisk wrote:
On Sun, 3 Oct 2010 18:00:03 -0500
"Snag" wrote:

snip
It would be a lot easier that way , without drive components
complicating things . If you can find that snapshot I'd appreciate
it ! My reply-to is good ...

It took some digging...

This is the web page that Wes made:

http://garage-machinist.com/BuckleyOldeEngineShow/2008/

Take a look at the first four pictures. Not quite how I remembered it
but maybe it will give you some ideas...

--
Leon Fisk
Grand Rapids MI/Zone 5b
Remove no.spam for email

Very interesting indeed ! Thanks for the link .

--
Snag
Wannabe Machinist

On Mon, 4 Oct 2010 08:00:32 -0500, "Snag"
wrote:

Karl Townsend wrote:
I'd settle for a set of sketches of the geometry ... the budget on
this one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get for
it . Probably somewhere in the $700-$900 range - which will buy the
materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the Honda
750, its chain drive) Then take the smallest rear wheel drive car you
can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would be a
nightmare to design.

Karl

Well , the thing is that I already have the CB750 , and it's paid for .
Got some ideas for casting a housing for the diff out of aluminum I have on
hand ... start with a lost-foam casting , or maybe make a wood pattern that
I can alter for offset depth to accomodate the sprocket , since it's
off-center . Might be able to incorporate a single 4-pot caliper on the diff
housing , that'd simplify things a lot too .
Ideas , ideas , streaming thru my head ... I had a hard time getting to
sleep last night .
You do NOT want a single rear wheel brake on a trike - trust me.

On Sun, 03 Oct 2010 19:29:02 -0400, wrote:

On Sun, 3 Oct 2010 16:24:23 -0400, Leon Fisk
wrote:

On Sun, 3 Oct 2010 08:06:22 -0500
"Snag" wrote:

snip
I'm debating building a trike rear end
to put on an older Honda CB750...

Have you considered a trike front end? In my eyes this would be a
simpler task. I think it was Wes who took a picture of one several years
ago. It was an older motorcycle, like a 750. He might still have the
picture around somewhere. Pretty sure I saved it too, but where on the
hard drive is the question I'll go searching for it (picture) if you
want to pursue this idea.
A WHOLE LOT more surefooted in the handling department. Think Morgan
vs Reliant Robin.

Snowmobile ski suspension components will work for most of the setup.
- trailing arms back to footpeg area etc.

On 10/04/2010 12:36 PM, Leon Fisk wrote:
On Sun, 3 Oct 2010 18:00:03 -0500
wrote:

snip
It would be a lot easier that way , without drive components complicating
things . If you can find that snapshot I'd appreciate it ! My reply-to is
good ...

It took some digging...

This is the web page that Wes made:

http://garage-machinist.com/BuckleyOldeEngineShow/2008/

Take a look at the first four pictures. Not quite how I remembered it
but maybe it will give you some ideas...

It sure looks cool!

I would have done the same thing with a double wishbone suspension, and
maybe little car tires. If you go that way, keep in mind that the
geometry that's right for a single motorcycle wheel may lead to
horrendous bump steer and other difficulties on a vehicle that will
essentially handle like a car.

But it sure looks cool.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html

wrote:
On Mon, 4 Oct 2010 08:00:32 -0500, "Snag"
wrote:

Karl Townsend wrote:
I'd settle for a set of sketches of the geometry ... the budget on
this one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get for
it . Probably somewhere in the $700-$900 range - which will buy the
materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the Honda
750, its chain drive) Then take the smallest rear wheel drive car
you can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would be a
nightmare to design.

Karl

Well , the thing is that I already have the CB750 , and it's paid
for . Got some ideas for casting a housing for the diff out of
aluminum I have on hand ... start with a lost-foam casting , or
maybe make a wood pattern that I can alter for offset depth to
accomodate the sprocket , since it's off-center . Might be able to
incorporate a single 4-pot caliper on the diff housing , that'd
simplify things a lot too . Ideas , ideas , streaming thru my head
... I had a hard time getting to sleep last night .
You do NOT want a single rear wheel brake on a trike - trust me.

It wouldn't be on a wheel , but on the spider/differential housing . Still ,
there is a chance of unequal braking with a normal differential - but if
it's limited slip ...

--
Snag
Wannabe Machinist

On Mon, 4 Oct 2010 16:21:34 -0500, "Snag"
wrote:

wrote:
On Mon, 4 Oct 2010 08:00:32 -0500, "Snag"
wrote:

Karl Townsend wrote:
I'd settle for a set of sketches of the geometry ... the budget on
this one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get for
it . Probably somewhere in the $700-$900 range - which will buy the
materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the Honda
750, its chain drive) Then take the smallest rear wheel drive car
you can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would be a
nightmare to design.

Karl

Well , the thing is that I already have the CB750 , and it's paid
for . Got some ideas for casting a housing for the diff out of
aluminum I have on hand ... start with a lost-foam casting , or
maybe make a wood pattern that I can alter for offset depth to
accomodate the sprocket , since it's off-center . Might be able to
incorporate a single 4-pot caliper on the diff housing , that'd
simplify things a lot too . Ideas , ideas , streaming thru my head
... I had a hard time getting to sleep last night .
You do NOT want a single rear wheel brake on a trike - trust me.

It wouldn't be on a wheel , but on the spider/differential housing . Still ,
there is a chance of unequal braking with a normal differential - but if
it's limited slip ...
Likited slip on a short coupled trike with a light front end is
asking for trouble. You DO want to be able to steer it on damp or wet
pavement.

Be safe. Use a brake on each rear wheel (inboard or outboard doesn't
matter) and an open differential.

On Mon, 04 Oct 2010 13:43:54 -0700, Tim Wescott
wrote:

On 10/04/2010 12:36 PM, Leon Fisk wrote:
On Sun, 3 Oct 2010 18:00:03 -0500
wrote:

snip
It would be a lot easier that way , without drive components complicating
things . If you can find that snapshot I'd appreciate it ! My reply-to is
good ...

It took some digging...

This is the web page that Wes made:

http://garage-machinist.com/BuckleyOldeEngineShow/2008/

Take a look at the first four pictures. Not quite how I remembered it
but maybe it will give you some ideas...

It sure looks cool!

I would have done the same thing with a double wishbone suspension, and
maybe little car tires. If you go that way, keep in mind that the
geometry that's right for a single motorcycle wheel may lead to
horrendous bump steer and other difficulties on a vehicle that will
essentially handle like a car.

But it sure looks cool.
Put a "bug" front axle on it. You can narrow it easily - and lighten
the torsion rods (or remove them and install coil-overs)

wrote:
On Mon, 4 Oct 2010 16:21:34 -0500, "Snag"
wrote:

wrote:
On Mon, 4 Oct 2010 08:00:32 -0500, "Snag"
wrote:

Karl Townsend wrote:
I'd settle for a set of sketches of the geometry ... the budget
on this one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get
for it . Probably somewhere in the $700-$900 range - which will
buy the materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the
Honda 750, its chain drive) Then take the smallest rear wheel
drive car you can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would
be a nightmare to design.

Karl

Well , the thing is that I already have the CB750 , and it's paid
for . Got some ideas for casting a housing for the diff out of
aluminum I have on hand ... start with a lost-foam casting , or
maybe make a wood pattern that I can alter for offset depth to
accomodate the sprocket , since it's off-center . Might be able to
incorporate a single 4-pot caliper on the diff housing , that'd
simplify things a lot too . Ideas , ideas , streaming thru my head
... I had a hard time getting to sleep last night .
You do NOT want a single rear wheel brake on a trike - trust me.

It wouldn't be on a wheel , but on the spider/differential housing .
Still , there is a chance of unequal braking with a normal
differential - but if it's limited slip ...
Likited slip on a short coupled trike with a light front end is
asking for trouble. You DO want to be able to steer it on damp or wet
pavement.

Be safe. Use a brake on each rear wheel (inboard or outboard doesn't
matter) and an open differential.

And it's just this sort of input I was looking for ! Everyone who has
contributed to this thread has given me a perspective on the project that I
might have missed . And I want to thank all of you for your help !!
Got some studying to do . I understand the basic principles of the subject
, now to really dig in and learn some of the finer points . Balsa wood and
straight pins , since I don't have the modeling software I can do some scale
models to verify that my calcs are right ... and to better understand how
changing one thing can affect the entire system .
--
Snag
Inboard brakes lower unsprung weight ...

Snag wrote:
wrote:
On Mon, 4 Oct 2010 16:21:34 -0500, "Snag"
wrote:

wrote:
On Mon, 4 Oct 2010 08:00:32 -0500, "Snag"
wrote:

Karl Townsend wrote:
I'd settle for a set of sketches of the geometry ... the budget
on this one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get
for it . Probably somewhere in the $700-$900 range - which will
buy the materials (I hope !) .
If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the
Honda 750, its chain drive) Then take the smallest rear wheel
drive car you can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would
be a nightmare to design.

Karl
Well , the thing is that I already have the CB750 , and it's paid
for . Got some ideas for casting a housing for the diff out of
aluminum I have on hand ... start with a lost-foam casting , or
maybe make a wood pattern that I can alter for offset depth to
accomodate the sprocket , since it's off-center . Might be able to
incorporate a single 4-pot caliper on the diff housing , that'd
simplify things a lot too . Ideas , ideas , streaming thru my head
... I had a hard time getting to sleep last night .
You do NOT want a single rear wheel brake on a trike - trust me.
It wouldn't be on a wheel , but on the spider/differential housing .
Still , there is a chance of unequal braking with a normal
differential - but if it's limited slip ...
Likited slip on a short coupled trike with a light front end is
asking for trouble. You DO want to be able to steer it on damp or wet
pavement.

Be safe. Use a brake on each rear wheel (inboard or outboard doesn't
matter) and an open differential.

And it's just this sort of input I was looking for ! Everyone who has
contributed to this thread has given me a perspective on the project that I
might have missed . And I want to thank all of you for your help !!
Got some studying to do . I understand the basic principles of the subject
, now to really dig in and learn some of the finer points . Balsa wood and
straight pins , since I don't have the modeling software I can do some scale
models to verify that my calcs are right ... and to better understand how
changing one thing can affect the entire system .
--
Snag
Inboard brakes lower unsprung weight ...




Welcome to real engineering, Snag!

It outta be a fun project.



--

Richard Lamb

On 10/04/2010 06:19 PM, wrote:
On Mon, 04 Oct 2010 13:43:54 -0700, Tim
wrote:

On 10/04/2010 12:36 PM, Leon Fisk wrote:
On Sun, 3 Oct 2010 18:00:03 -0500
wrote:

snip
It would be a lot easier that way , without drive components complicating
things . If you can find that snapshot I'd appreciate it ! My reply-to is
good ...

It took some digging...

This is the web page that Wes made:

http://garage-machinist.com/BuckleyOldeEngineShow/2008/

Take a look at the first four pictures. Not quite how I remembered it
but maybe it will give you some ideas...

It sure looks cool!

I would have done the same thing with a double wishbone suspension, and
maybe little car tires. If you go that way, keep in mind that the
geometry that's right for a single motorcycle wheel may lead to
horrendous bump steer and other difficulties on a vehicle that will
essentially handle like a car.

But it sure looks cool.
Put a "bug" front axle on it. You can narrow it easily - and lighten
the torsion rods (or remove them and install coil-overs)

There's a lot of options there. Just about anything from out of a car
would be hard to make look good. Whomping up a dual-wishbone IFS from
tubing would look good -- even painted it'd look good -- but would take
some time in jigging, and you'd be at the mercy of your own ignorance
with the handling. You could do a straight axle, at the cost of some
really horrendous and hard to control oversteer. You could do a "1960's
Ford pickup" style front axle, i.e. a straight axle that's been split
and the ends overlapped, for a simplified, but probably still
prone-to-oversteer front end.

So Snag: When it comes to oversteer vs. understeer, does your wife
prefer to go into the pucker brush front-first, or back-first?

Spindles would be an issue, wouldn't they? You could make 'em, and take
the "wannabe" out of your tag line when you're done. Or you could try
to find a suitable donor car (egad).

Other than the bug I can't think of many really small rear-wheel drive
cars, unless you want to cruise the junk yards looking for Toyotas &c
from the early 70's. Or maybe something like a Honda or Mazda rear
spindle could be adapted? I have Absolutely No Clue (TM) how much of a
pain this would be -- you'd almost want to have a spindle part that you
kept, then machine off all the features on the back and bolt it to a
backing plate/steering adapter with the same bolts that would normally
bolt the brakes on.

Motorcycle spindles wouldn't work 'cause they're designed to hang the
axle on both sides.

Etc.

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html

T -- but would take
some time in jigging, and you'd be at the mercy of your own ignorance
with the handling. You could do a straight axle, at the cost of some
really horrendous and hard to control oversteer. You could do a "1960's
Ford pickup" style front axle, i.e. a straight axle that's been split
and the ends overlapped, for a simplified, but probably still
prone-to-oversteer front end.

So Snag: When it comes to oversteer vs. understeer, does your wife
prefer to go into the pucker brush front-first, or back-first?


What Tim said, Snag.

Best option, as a rider, ride two wheels.

That's the best option there is...

Best maneuverability...

Best survivability...

Ride the damned bike.

K?

In article ,
says...

Cross-Slide wrote:
On Oct 4, 8:00 am, "Snag" wrote:
Karl Townsend wrote:
I'd settle for a set of sketches of the geometry ... the budget on
this one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get for
it . Probably somewhere in the $700-$900 range - which will buy the
materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the Honda
750, its chain drive) Then take the smallest rear wheel drive car
you can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would be a
nightmare to design.

Karl

Well , the thing is that I already have the CB750 , and it's paid
for .
Got some ideas for casting a housing for the diff out of aluminum I
have on hand ... start with a lost-foam casting , or maybe make a
wood pattern that I can alter for offset depth to accomodate the
sprocket , since it's off-center . Might be able to incorporate a
single 4-pot caliper on the diff housing , that'd simplify things a
lot too .
Ideas , ideas , streaming thru my head ... I had a hard time getting
to sleep last night .
--
Snag
Wannabe Machinist

Pay close attention to the "Roll Center" of you suspension.
It is what made the Beetle, and the Corvair so "Exciting" to drive.

With a four bar linkage, the links point off into space to the
"reaction point" that imaginary point where the linkages intersect off
in space. THAT is the (instantaneous) point where the wheel pivots
around as it moves up and down.
As the wheel moves up and down that point in space moves too.

You can draw a line from the point of contact on the road to that
instantaneous center and where it crosses above or below you center of
mass is the Roll Center.
If the Roll center gets too high, it tries to jack up that corner of
the vehicle, and tuck that tire underneath. That is wha the Beetles
and Corvair did in a hard corner.

They basically swiveled the rear axle shaft from a single U-joint on
the trans-axle, and that became the Roll center.

If you look at a Corvette or a Jaguar independent suspension, they
have two u-joints and the roll centers are established by the
linkages. The instantaneous center can be anywhere, as set by the
geometry of the linkages.

A Front wheel drive will typically use McPherson struts with a single
lower A arm. That might not be acceptable for your layout. So, finding
the appropriate uprights will be one of the many tricks, or problems
to solve.

Another consideration will be camber gain/loss as the suspension
travels.
And any amount of bump steer. (!)
If on the front of a vehicle, a wheel hits a bump, and that for
example causes that wheel to turn towards the center line, the car
will react as if it is going into a turn, And exaggerate the bump, and
exaggerate the unintended turn, etc.
The vehicle will dart about on a bumpy road.
For example, the right front tire turns so very slightly to the left
as it hits a bump, and visa-versa. The vehicle will dart and skitter
over bumps or ripples. If the wheel bump steers in the other direction
it will be more stable.
This is also important in the back of the vehicle.

There is also anti-dive built into suspension. The brake reaction
torque on the front end will try to make it rise slightly, to overcome
the tendency to nose-dive on braking. This is a function of the front
end A-Arm geometry.
This also affects the rear end.

I don't have enough life expectancy to spend it re-typing several
entire books here.
But there are some important considerations. It is not too complicated
once you understand the principles.

It is no more complicated than understanding gear ratios before you
set out to design or build a transmission from a stack of totally
random gears. You would need to understand ratios, ratio spreads and
other stuff to make it work. But you at least have to know something
about it before you started to make it work "acceptably" the first
time.

Getting a suspension system nearly correct might be perfectly fine
until you hit that first pothole with the wrong wheel while going
around a corner, with just a little mist on the road.......

This might a good place to start.
http://www.carrollsmith.com/books/

I hit a website Sat. night that explained all this you've said in great
detail . And that's the reason I choose to use an unequal length a-frame
type of suspension . I can build in the proper camber characteristics , set
the drive components so there's no "zero movement" in the CV joints , and of
course set it up so the instantaneous roll center stays close to or below
the center of mass . I'm still studying , and will not cut the first chunk
of steel until I'm satisfied that my design will do what I intend it to do .
The woman I love will be ridin' this thing , should it ever come to more
than just talk . And you can bet your sweet a$$ I'm going to make sure she's
as safe as I can possibly make her .
My first car was a '62 Pontiac Tempest , used that infamous Corvair
transaxle that Ralphie got in such a tizzy over . You're right , it was
unsafe under certain conditions . But it left the coolest burnouts ...

Have you seen "My Cousin Vinnie"? If not, I think you might want to.
After you've seen it you'll know what made me think of it.

CaveLamb wrote:
T -- but would take
some time in jigging, and you'd be at the mercy of your own ignorance
with the handling. You could do a straight axle, at the cost of some
really horrendous and hard to control oversteer. You could do a
"1960's Ford pickup" style front axle, i.e. a straight axle that's
been split and the ends overlapped, for a simplified, but probably
still prone-to-oversteer front end.

So Snag: When it comes to oversteer vs. understeer, does your wife
prefer to go into the pucker brush front-first, or back-first?


What Tim said, Snag.

Best option, as a rider, ride two wheels.

That's the best option there is...

Best maneuverability...

Best survivability...

Ride the damned bike.

K?

Hey , you don't have to sell me ! My ride is a '90 Harley FLHTCU , and my
chicken strips are as narrow as they can get without draggin' hard parts .
If I had my way she'd be ridin' that Kaw EX250 until she outgrew it , then
on to something bigger . But she wants what she wants , and I love her and
want her to be happy . May end up talkin' to a guy that lives near Memphis
who has built several car-based trikes , might be better off with something
bigger and heavier than a CB750 based unit . Start with a FWD subframe ...
We saw some awesome trikes at Mountains , Music , and Motorcycles up in
Mountain View Ar. last month , I think that's where that particular seed got
planted .
--
Snag
Wannabe Machinist

On 10/4/2010 2:34 PM, Snag wrote:
Cross-Slide wrote:
On Oct 4, 8:00 am, wrote:
Karl Townsend wrote:
I'd settle for a set of sketches of the geometry ... the budget on
this one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get for
it . Probably somewhere in the $700-$900 range - which will buy the
materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the Honda
750, its chain drive) Then take the smallest rear wheel drive car
you can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would be a
nightmare to design.

Karl

Well , the thing is that I already have the CB750 , and it's paid
for .
Got some ideas for casting a housing for the diff out of aluminum I
have on hand ... start with a lost-foam casting , or maybe make a
wood pattern that I can alter for offset depth to accomodate the
sprocket , since it's off-center . Might be able to incorporate a
single 4-pot caliper on the diff housing , that'd simplify things a
lot too .
Ideas , ideas , streaming thru my head ... I had a hard time getting
to sleep last night .
--
Snag
Wannabe Machinist

Pay close attention to the "Roll Center" of you suspension.
It is what made the Beetle, and the Corvair so "Exciting" to drive.

With a four bar linkage, the links point off into space to the
"reaction point" that imaginary point where the linkages intersect off
in space. THAT is the (instantaneous) point where the wheel pivots
around as it moves up and down.
As the wheel moves up and down that point in space moves too.

You can draw a line from the point of contact on the road to that
instantaneous center and where it crosses above or below you center of
mass is the Roll Center.
If the Roll center gets too high, it tries to jack up that corner of
the vehicle, and tuck that tire underneath. That is wha the Beetles
and Corvair did in a hard corner.

They basically swiveled the rear axle shaft from a single U-joint on
the trans-axle, and that became the Roll center.

If you look at a Corvette or a Jaguar independent suspension, they
have two u-joints and the roll centers are established by the
linkages. The instantaneous center can be anywhere, as set by the
geometry of the linkages.

A Front wheel drive will typically use McPherson struts with a single
lower A arm. That might not be acceptable for your layout. So, finding
the appropriate uprights will be one of the many tricks, or problems
to solve.

Another consideration will be camber gain/loss as the suspension
travels.
And any amount of bump steer. (!)
If on the front of a vehicle, a wheel hits a bump, and that for
example causes that wheel to turn towards the center line, the car
will react as if it is going into a turn, And exaggerate the bump, and
exaggerate the unintended turn, etc.
The vehicle will dart about on a bumpy road.
For example, the right front tire turns so very slightly to the left
as it hits a bump, and visa-versa. The vehicle will dart and skitter
over bumps or ripples. If the wheel bump steers in the other direction
it will be more stable.
This is also important in the back of the vehicle.

There is also anti-dive built into suspension. The brake reaction
torque on the front end will try to make it rise slightly, to overcome
the tendency to nose-dive on braking. This is a function of the front
end A-Arm geometry.
This also affects the rear end.

I don't have enough life expectancy to spend it re-typing several
entire books here.
But there are some important considerations. It is not too complicated
once you understand the principles.

It is no more complicated than understanding gear ratios before you
set out to design or build a transmission from a stack of totally
random gears. You would need to understand ratios, ratio spreads and
other stuff to make it work. But you at least have to know something
about it before you started to make it work "acceptably" the first
time.

Getting a suspension system nearly correct might be perfectly fine
until you hit that first pothole with the wrong wheel while going
around a corner, with just a little mist on the road.......

This might a good place to start.
http://www.carrollsmith.com/books/

I hit a website Sat. night that explained all this you've said in great
detail . And that's the reason I choose to use an unequal length a-frame
type of suspension . I can build in the proper camber characteristics , set
the drive components so there's no "zero movement" in the CV joints , and of
course set it up so the instantaneous roll center stays close to or below
the center of mass . I'm still studying , and will not cut the first chunk
of steel until I'm satisfied that my design will do what I intend it to do .
The woman I love will be ridin' this thing , should it ever come to more
than just talk . And you can bet your sweet a$$ I'm going to make sure she's
as safe as I can possibly make her .
My first car was a '62 Pontiac Tempest , used that infamous Corvair
transaxle that Ralphie got in such a tizzy over . You're right , it was
unsafe under certain conditions . But it left the coolest burnouts ...

Speedo-cable driveshaft?

It would do burnouts? Who knew?

--
I can see November from my front porch

On 10/4/2010 8:43 PM, Snag wrote:
wrote:
On Mon, 4 Oct 2010 16:21:34 -0500,
wrote:

wrote:
On Mon, 4 Oct 2010 08:00:32 -0500,
wrote:

Karl Townsend wrote:
I'd settle for a set of sketches of the geometry ... the budget
on this one is "do it yourself or you can't afford it" .
We've decided to sell her Kawasaki since she's just not all that
hot on leaning into turns , and my budget is whatever I can get
for it . Probably somewhere in the $700-$900 range - which will
buy the materials (I hope !) .

If you're rolling yer own...

Can you start with a shaft drive bike? (That would not be the
Honda 750, its chain drive) Then take the smallest rear wheel
drive car you can find for drive and suspension parts.

I've seen a few people that can just do this. For most it would
be a nightmare to design.

Karl

Well , the thing is that I already have the CB750 , and it's paid
for . Got some ideas for casting a housing for the diff out of
aluminum I have on hand ... start with a lost-foam casting , or
maybe make a wood pattern that I can alter for offset depth to
accomodate the sprocket , since it's off-center . Might be able to
incorporate a single 4-pot caliper on the diff housing , that'd
simplify things a lot too . Ideas , ideas , streaming thru my head
... I had a hard time getting to sleep last night .
You do NOT want a single rear wheel brake on a trike - trust me.

It wouldn't be on a wheel , but on the spider/differential housing .
Still , there is a chance of unequal braking with a normal
differential - but if it's limited slip ...
Likited slip on a short coupled trike with a light front end is
asking for trouble. You DO want to be able to steer it on damp or wet
pavement.

Be safe. Use a brake on each rear wheel (inboard or outboard doesn't
matter) and an open differential.

And it's just this sort of input I was looking for ! Everyone who has
contributed to this thread has given me a perspective on the project that I
might have missed . And I want to thank all of you for your help !!
Got some studying to do . I understand the basic principles of the subject
, now to really dig in and learn some of the finer points . Balsa wood and
straight pins , since I don't have the modeling software I can do some scale
models to verify that my calcs are right ... and to better understand how
changing one thing can affect the entire system .
--
Snag
Inboard brakes lower unsprung weight ...

I'd be looking at ATVs. They have sophisticated front suspensions scaled
correctly to your project, usually of welded tubes that look good. All
the geometry is done. And they have rear differentials and IRS
all-around. So you could get components for either 2(front)-1(Rear) or
1-2 configuration.
I'd keep an eye out on both Craigslist and also any active hunting
forums. You might find a wrecked or locked-up ATV for cheap. You might
also see if there is someone who repairs them, who might have some in
back that he salvages from.
Sounds like you are leaning toward 1-2. I'd prefer the 2-1, but then
I'm a sporty-car kinda guy.

Here's an example. Sounds like he values it around $500

http://dallas.craigslist.org/dal/rvs/1989355251.html

Wow, here's your deal:

http://dallas.craigslist.org/ndf/rvs/1988740364.html


--
I can see November from my front porch

RBnDFW wrote:
On 10/4/2010 2:34 PM, Snag wrote:
My first car
was a '62 Pontiac Tempest , used that infamous Corvair transaxle
that Ralphie got in such a tizzy over . You're right , it was unsafe
under certain conditions . But it left the coolest burnouts ...

Speedo-cable driveshaft?

It would do burnouts? Who knew?

--
I can see November from my front porch

That driveshaft was a piece of steel bar stock about an inch or better in
diameter with a flanged stub shaft into the clutch hub . Enclosed in a tube
, with at least one mid support bearing . The shifter lever on that ol' 3
speed would often pop the ball outta the socket , leaving you in 2nd gear if
you shifted too hard . I carried a 7/16 wrench to pull the cover off to fix
it .
Those were the daze , 35 MPG and gas at two bits a gallon .
--
Snag
Wannabe Machinist

RBnDFW wrote:

I'd keep an eye out on both Craigslist and also any active hunting
forums. You might find a wrecked or locked-up ATV for cheap. You might
also see if there is someone who repairs them, who might have some in
back that he salvages from.
Sounds like you are leaning toward 1-2. I'd prefer the 2-1, but
then I'm a sporty-car kinda guy.

Here's an example. Sounds like he values it around $500

http://dallas.craigslist.org/dal/rvs/1989355251.html

Wow, here's your deal:

http://dallas.craigslist.org/ndf/rvs/1988740364.html


--
I can see November from my front porch

Too bad that second one is in Texas !

--
Snag
Wannabe Machinist

On 10/5/2010 10:02 AM, Snag wrote:
RBnDFW wrote:

I'd keep an eye out on both Craigslist and also any active hunting
forums. You might find a wrecked or locked-up ATV for cheap. You might
also see if there is someone who repairs them, who might have some in
back that he salvages from.
Sounds like you are leaning toward 1-2. I'd prefer the 2-1, but
then I'm a sporty-car kinda guy.

Here's an example. Sounds like he values it around $500

http://dallas.craigslist.org/dal/rvs/1989355251.html

Wow, here's your deal:

http://dallas.craigslist.org/ndf/rvs/1988740364.html


--
I can see November from my front porch

Too bad that second one is in Texas !


For $75 I'd try to get him to ship it.
I'd almost run over and buy it myself for that kind of money.

--
I can see November from my front porch

On 10/5/2010 10:02 AM, Snag wrote:
RBnDFW wrote:

I'd keep an eye out on both Craigslist and also any active hunting
forums. You might find a wrecked or locked-up ATV for cheap. You might
also see if there is someone who repairs them, who might have some in
back that he salvages from.
Sounds like you are leaning toward 1-2. I'd prefer the 2-1, but
then I'm a sporty-car kinda guy.

Here's an example. Sounds like he values it around $500

http://dallas.craigslist.org/dal/rvs/1989355251.html

Wow, here's your deal:

http://dallas.craigslist.org/ndf/rvs/1988740364.html


--
I can see November from my front porch

Too bad that second one is in Texas !


look at the rear view of this thing - it's perfect!

http://www.amazon.com/Honda-300EX-Re.../dp/B002SZAEGA

--
I can see November from my front porch

On 10/03/2010 06:06 AM, Snag wrote:
I seem to recall someone (or more than one ...) here is/was involved in
building tube frames for race cars . I'm debating building a trike rear end
to put on an older Honda CB750 , and need a bit of guidance ... my wife
wants to ride but doesn't like to lean .
Looks like the best-handling option is going to be unequal length A-frames
with CV jointed half shafts and dual inboard disc brakes . I'm undecided
about springing options , whether coil-over shocks , maybe a single
transverse leaf . Either option will require a torsion bar to control body
roll . Going to have to have an enclosed spider differential setup , with a
sprocket mounted for chain drive - maybe from an ATV ? Front suspension hubs
from a FWD car look like the cheapest option ...
And it all needs to fit into a 14 x 14 x 27 inch package , plus the width
of the A-frames , and the mounting points extending to the front to bolt it
to the M/C frame . I'm considering using 1" sq tube and 1x2" tube for the
frame members . I'd like to use the original swingarm and shock absorber
mount points , since they're designed to support the loads ... and I
haven'rt even begun to consider body work to cover it all .

I think you need to check out this page:

http://reversetrike.com/home.html

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html

Tim Wescott wrote:
On 10/03/2010 06:06 AM, Snag wrote:
I seem to recall someone (or more than one ...) here is/was
involved in building tube frames for race cars . I'm debating
building a trike rear end to put on an older Honda CB750 , and need
a bit of guidance ... my wife wants to ride but doesn't like to lean
. Looks like the best-handling option is going to be unequal
length A-frames with CV jointed half shafts and dual inboard disc
brakes . I'm undecided about springing options , whether coil-over
shocks , maybe a single transverse leaf . Either option will require
a torsion bar to control body roll . Going to have to have an
enclosed spider differential setup , with a sprocket mounted for
chain drive - maybe from an ATV ? Front suspension hubs from a FWD
car look like the cheapest option ... And it all needs to fit
into a 14 x 14 x 27 inch package , plus the width of the A-frames ,
and the mounting points extending to the front to bolt it to the M/C
frame . I'm considering using 1" sq tube and 1x2" tube for the frame
members . I'd like to use the original swingarm and shock absorber
mount points , since they're designed to support the loads ... and I
haven'rt even begun to consider body work to cover it all .

I think you need to check out this page:

http://reversetrike.com/home.html

--

Tim Wescott

There's a new subfolder in my favorites folger , and it's called trike links
.. That one's in there ... alone so far , but I hope to change that !

--
Snag
Wannabe Machinist

On 10/05/2010 03:22 PM, Snag wrote:
Tim Wescott wrote:
On 10/03/2010 06:06 AM, Snag wrote:
I seem to recall someone (or more than one ...) here is/was
involved in building tube frames for race cars . I'm debating
building a trike rear end to put on an older Honda CB750 , and need
a bit of guidance ... my wife wants to ride but doesn't like to lean
. Looks like the best-handling option is going to be unequal
length A-frames with CV jointed half shafts and dual inboard disc
brakes . I'm undecided about springing options , whether coil-over
shocks , maybe a single transverse leaf . Either option will require
a torsion bar to control body roll . Going to have to have an
enclosed spider differential setup , with a sprocket mounted for
chain drive - maybe from an ATV ? Front suspension hubs from a FWD
car look like the cheapest option ... And it all needs to fit
into a 14 x 14 x 27 inch package , plus the width of the A-frames ,
and the mounting points extending to the front to bolt it to the M/C
frame . I'm considering using 1" sq tube and 1x2" tube for the frame
members . I'd like to use the original swingarm and shock absorber
mount points , since they're designed to support the loads ... and I
haven'rt even begun to consider body work to cover it all .

I think you need to check out this page:

http://reversetrike.com/home.html

--

Tim Wescott

There's a new subfolder in my favorites folger , and it's called trike links
. That one's in there ... alone so far , but I hope to change that !

What I was really looking for was a site for a shop in Washington that
custom builds Morgan-inspired, Harley-powered trikes. They cost over
$40000 new, IIRC, and they are absolutely gorgeous. I was going to say
"don't show her this link!!!".

--

Tim Wescott
Wescott Design Services
http://www.wescottdesign.com

Do you need to implement control loops in software?
"Applied Control Theory for Embedded Systems" was written for you.
See details at http://www.wescottdesign.com/actfes/actfes.html

On Tue, 05 Oct 2010 11:33:54 -0500, RBnDFW
wrote:

On 10/5/2010 10:02 AM, Snag wrote:
RBnDFW wrote:

I'd keep an eye out on both Craigslist and also any active hunting
forums. You might find a wrecked or locked-up ATV for cheap. You might
also see if there is someone who repairs them, who might have some in
back that he salvages from.
Sounds like you are leaning toward 1-2. I'd prefer the 2-1, but
then I'm a sporty-car kinda guy.

Here's an example. Sounds like he values it around $500

http://dallas.craigslist.org/dal/rvs/1989355251.html

Wow, here's your deal:

http://dallas.craigslist.org/ndf/rvs/1988740364.html


--
I can see November from my front porch

Too bad that second one is in Texas !


look at the rear view of this thing - it's perfect!

http://www.amazon.com/Honda-300EX-Re.../dp/B002SZAEGA
Removing the "suspension" tires I'm not sure if I'd want the
unsupported axles on a road machine. The diff and brakes would be a
good start though.

On Mon, 04 Oct 2010 20:43:33 -0700, Tim Wescott
wrote:

On 10/04/2010 06:19 PM, wrote:
On Mon, 04 Oct 2010 13:43:54 -0700, Tim
wrote:

On 10/04/2010 12:36 PM, Leon Fisk wrote:
On Sun, 3 Oct 2010 18:00:03 -0500
wrote:

snip
It would be a lot easier that way , without drive components complicating
things . If you can find that snapshot I'd appreciate it ! My reply-to is
good ...

It took some digging...

This is the web page that Wes made:

http://garage-machinist.com/BuckleyOldeEngineShow/2008/

Take a look at the first four pictures. Not quite how I remembered it
but maybe it will give you some ideas...

It sure looks cool!

I would have done the same thing with a double wishbone suspension, and
maybe little car tires. If you go that way, keep in mind that the
geometry that's right for a single motorcycle wheel may lead to
horrendous bump steer and other difficulties on a vehicle that will
essentially handle like a car.

But it sure looks cool.
Put a "bug" front axle on it. You can narrow it easily - and lighten
the torsion rods (or remove them and install coil-overs)

There's a lot of options there. Just about anything from out of a car
would be hard to make look good. Whomping up a dual-wishbone IFS from
tubing would look good -- even painted it'd look good -- but would take
some time in jigging, and you'd be at the mercy of your own ignorance
with the handling. You could do a straight axle, at the cost of some
really horrendous and hard to control oversteer. You could do a "1960's
Ford pickup" style front axle, i.e. a straight axle that's been split
and the ends overlapped, for a simplified, but probably still
prone-to-oversteer front end.

So Snag: When it comes to oversteer vs. understeer, does your wife
prefer to go into the pucker brush front-first, or back-first?

Spindles would be an issue, wouldn't they? You could make 'em, and take
the "wannabe" out of your tag line when you're done. Or you could try
to find a suitable donor car (egad).

Other than the bug I can't think of many really small rear-wheel drive
cars, unless you want to cruise the junk yards looking for Toyotas &c
from the early 70's. Or maybe something like a Honda or Mazda rear
spindle could be adapted? I have Absolutely No Clue (TM) how much of a
pain this would be -- you'd almost want to have a spindle part that you
kept, then machine off all the features on the back and bolt it to a
backing plate/steering adapter with the same bolts that would normally
bolt the brakes on.

Motorcycle spindles wouldn't work 'cause they're designed to hang the
axle on both sides.

Etc.
Unless you get a uni-strut / uni-fork type MC suspension.

On 10/5/2010 6:37 PM, wrote:
On Tue, 05 Oct 2010 11:33:54 -0500,
wrote:

On 10/5/2010 10:02 AM, Snag wrote:
RBnDFW wrote:

I'd keep an eye out on both Craigslist and also any active hunting
forums. You might find a wrecked or locked-up ATV for cheap. You might
also see if there is someone who repairs them, who might have some in
back that he salvages from.
Sounds like you are leaning toward 1-2. I'd prefer the 2-1, but
then I'm a sporty-car kinda guy.

Here's an example. Sounds like he values it around $500

http://dallas.craigslist.org/dal/rvs/1989355251.html

Wow, here's your deal:

http://dallas.craigslist.org/ndf/rvs/1988740364.html


--
I can see November from my front porch

Too bad that second one is in Texas !


look at the rear view of this thing - it's perfect!

http://www.amazon.com/Honda-300EX-Re.../dp/B002SZAEGA
Removing the "suspension" tires I'm not sure if I'd want the
unsupported axles on a road machine. The diff and brakes would be a
good start though.

I agree, this particular model is a lightweight 300cc.
Some of it's bigger brothers have a nice double-wishbone suspension
front and rear. Those also tend to be the models that get totaled out
more frequently, I'd imagine.

--
I can see November from my front porch

On Wed, 06 Oct 2010 08:44:02 -0500, RBnDFW
wrote:

On 10/5/2010 6:37 PM, wrote:
On Tue, 05 Oct 2010 11:33:54 -0500,
wrote:

On 10/5/2010 10:02 AM, Snag wrote:
RBnDFW wrote:

I'd keep an eye out on both Craigslist and also any active hunting
forums. You might find a wrecked or locked-up ATV for cheap. You might
also see if there is someone who repairs them, who might have some in
back that he salvages from.
Sounds like you are leaning toward 1-2. I'd prefer the 2-1, but
then I'm a sporty-car kinda guy.

Here's an example. Sounds like he values it around $500

http://dallas.craigslist.org/dal/rvs/1989355251.html

Wow, here's your deal:

http://dallas.craigslist.org/ndf/rvs/1988740364.html


--
I can see November from my front porch

Too bad that second one is in Texas !


look at the rear view of this thing - it's perfect!

http://www.amazon.com/Honda-300EX-Re.../dp/B002SZAEGA
Removing the "suspension" tires I'm not sure if I'd want the
unsupported axles on a road machine. The diff and brakes would be a
good start though.

I agree, this particular model is a lightweight 300cc.
Some of it's bigger brothers have a nice double-wishbone suspension
front and rear. Those also tend to be the models that get totaled out
more frequently, I'd imagine.
And when the 300s are totalled, the rear end is most likely severely
damaged.