UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 3,712
Default Tandems with two sets of gears?

Why aren't tandems made with two sets of gears? Then riders wouldn't have to pedal at the same rate, and changing your gear wouldn't have to be announced to the other rider.
  #2   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default Tandems with two sets of gears?

On Sun, 11 Jun 2017 12:00:49 +0100, "James Wilkinson Sword"
wrote:

Why aren't tandems made with two sets of gears? Then riders wouldn't have to pedal at the same rate, and changing your gear wouldn't have to be announced to the other rider.


Because the pedals would clash.

Cheers, T i m

  #3   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 2,640
Default Tandems with two sets of gears?

T i m wrote:
On Sun, 11 Jun 2017 12:00:49 +0100, "James Wilkinson Sword"
wrote:

Why aren't tandems made with two sets of gears? Then riders wouldn't have to pedal at the same rate, and changing your gear wouldn't have to be announced to the other rider.


Because the pedals would clash.

Cheers, T i m

Is that really the case Tim? I've looked at several online images of
tandem bikes and there would appear to be lots of clearance between the
swept diameter of the pedals even allowing for feet/toes overhanging.
I could imagine some balance problems with unsyncronised power strokes
perhaps.
Bob
  #4   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 2,580
Default Tandems with two sets of gears?

On 11/06/2017 12:11, T i m wrote:
On Sun, 11 Jun 2017 12:00:49 +0100, "James Wilkinson Sword"
wrote:

Why aren't tandems made with two sets of gears? Then riders wouldn't have to pedal at the same rate, and changing your gear wouldn't have to be announced to the other rider.


Because the pedals would clash.


You can get tandems with independent drive - both driving an
intermediate shaft via a freewheel. Though tandems have got longer as
people understood how to use big tubes to make a strong frame.

However I suspect different gearing would feel dreadful as the riders
went in and out of phase.

  #5   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 3,712
Default Tandems with two sets of gears?

On Sun, 11 Jun 2017 16:24:40 +0100, Clive George wrote:

On 11/06/2017 12:11, T i m wrote:
On Sun, 11 Jun 2017 12:00:49 +0100, "James Wilkinson Sword"
wrote:

Why aren't tandems made with two sets of gears? Then riders wouldn't have to pedal at the same rate, and changing your gear wouldn't have to be announced to the other rider.


Because the pedals would clash.


You can get tandems with independent drive - both driving an
intermediate shaft via a freewheel. Though tandems have got longer as
people understood how to use big tubes to make a strong frame.

However I suspect different gearing would feel dreadful as the riders
went in and out of phase.


I was thinking being out of phase would make the overall drive smoother, especially going up a steep hill, where a normal bicycle is very uneven.

--
"An abstract noun," the teacher said, "is something you can think of, but you can't touch it. Can you give me an example of one?"
"Sure," a teenage boy replied. "My father's new car."


  #6   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 950
Default Birdbrain Macaw (now "James Wilkinson" LOL), the SociopathicAttention Whore

On 11/06/2017 19:20, The Peeler wrote:
On Sun, 11 Jun 2017 18:48:39 +0100, Birdbrain Macaw (now "James Wilkinson"),
the pathological attention whore of all the uk ngs, blathered again:

I was thinking


THERE's the snag again, Birdbrain! BG



How do you have the energy or the time to reply to him?

--
Adam
  #7   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 2,580
Default Tandems with two sets of gears?

On 11/06/2017 18:48, James Wilkinson Sword wrote:
On Sun, 11 Jun 2017 16:24:40 +0100, Clive George


However I suspect different gearing would feel dreadful as the riders
went in and out of phase.


I was thinking being out of phase would make the overall drive smoother,
especially going up a steep hill, where a normal bicycle is very uneven.


Being 90 degrees out of phase is preferred by some teams - as you note,
it makes the load on the drive train components easier. But only some
teams - others, like us, don't like it. It feels wrong.

Note that's permanently out-of-phase, ie still pedalling at the same
rate. Different gearing would being you in and out of phase, which would
be worse.



  #8   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default Tandems with two sets of gears?

On Sun, 11 Jun 2017 15:54:34 +0100, Bob Minchin
wrote:

T i m wrote:
On Sun, 11 Jun 2017 12:00:49 +0100, "James Wilkinson Sword"
wrote:

Why aren't tandems made with two sets of gears? Then riders wouldn't have to pedal at the same rate, and changing your gear wouldn't have to be announced to the other rider.


Because the pedals would clash.


Is that really the case Tim?


I think it can be yes.

I've looked at several online images of
tandem bikes and there would appear to be lots of clearance between the
swept diameter of the pedals even allowing for feet/toes overhanging.


On our tandem and two riders with feet the same of mine, they might
still just miss (I've just checked). ;-)

But then the cranks for the stoker are slightly shorter ...

I could imagine some balance problems with unsyncronised power strokes
perhaps.


I just think it would look funny?

Cheers, T i m
  #9   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 2,570
Default Birdbrain Macaw (now "James Wilkinson" LOL), the SociopathicAttention Whore

On 11/06/2017 19:35, ARW wrote:
On 11/06/2017 19:20, The Peeler wrote:
On Sun, 11 Jun 2017 18:48:39 +0100, Birdbrain Macaw (now "James
Wilkinson"),
the pathological attention whore of all the uk ngs, blathered again:

I was thinking


THERE's the snag again, Birdbrain! BG



How do you have the energy or the time to reply to him?


The consequence of being jilted, though why anyone would want Peter's arse!

Haven't you had you fair share of stalkers, though not on the 'net?
  #10   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 2,570
Default Birdbrain Macaw (now "James Wilkinson" LOL), the SociopathicAttention Whore

On 11/06/2017 19:59, The Peeler wrote:
On Sun, 11 Jun 2017 20:20:55 +0200, The Peeler wrote:


I was thinking


THERE's the snag again, Birdbrain! BG


It's FUN! ;-)


It may be fun to you, but to us, only a sad desperate person could stalk
PHucker.


  #11   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 2,300
Default Birdbrain Macaw (now "James Wilkinson" LOL), the Sociopathic Attention Whore


"The Peeler" wrote in message
web.com...
On Sun, 11 Jun 2017 22:58:57 +0100, Fredxxx, the resident smartass,
smartassed again:


It's FUN! ;-)


It may be fun to you, but to us, only a sad desperate person could stalk
PHucker.


It's ESPECIALLY funny to see a notorious smartass like you actually
standing
up for the man he obviously has a liking for! VBG

Blimey


  #12   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 10,998
Default Tandems with two sets of gears?

Your mind does hop about a lot these days.
You almost want something like a reverse differential so that the power can
be shared.
Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please!
"James Wilkinson Sword" wrote in message
news
Why aren't tandems made with two sets of gears? Then riders wouldn't have
to pedal at the same rate, and changing your gear wouldn't have to be
announced to the other rider.



  #14   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default Tandems with two sets of gears?

On Mon, 12 Jun 2017 08:32:07 +0100, "Brian Gaff"
wrote:

Would that not depend on the spacing though?


It could do yes, but the chances are Tandems were smaller (shorter)
than they can be today and therefore they were more likely to clash.

Once the precedence was set ... ?

Cheers, T i m
  #15   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default Tandems with two sets of gears?

On Mon, 12 Jun 2017 08:31:22 +0100, "Brian Gaff"
wrote:

Your mind does hop about a lot these days.
You almost want something like a reverse differential so that the power can
be shared.


Funny you should say that ... I was looking at a tandem pedal boat the
other day where the two crew sit facing each other and pedal in a
recumbent style and both pedal forwards driving the same prop courtesy
of a small reverse diff. ;-)

Cheers, T i m


  #16   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 3,712
Default Tandems with two sets of gears?

My aunt just bought a tandem, and I thought it insane that they both have to pedal at the same speed.


On Mon, 12 Jun 2017 08:31:22 +0100, Brian Gaff wrote:

Your mind does hop about a lot these days.
You almost want something like a reverse differential so that the power can
be shared.
Brian



--
I was on a Southwest flight once that was delayed at the gate after everyone boarded. The flight attendant said over the intercom, "We're sorry for the delay. The machine that normally rips the handles off your luggage is broken, so we're having to do it by hand. We should be finished and on our way shortly."
  #17   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 3,712
Default Tandems with two sets of gears?

If you do a google image search (sorry Brian), all the results have the pedals nowhere near each other. I would have thought if they were close enough to touch, the two riders would be uncomfortably close together (or comfortably if they were naked).


On Mon, 12 Jun 2017 10:27:41 +0100, T i m wrote:

On Mon, 12 Jun 2017 08:32:07 +0100, "Brian Gaff"
wrote:

Would that not depend on the spacing though?


It could do yes, but the chances are Tandems were smaller (shorter)
than they can be today and therefore they were more likely to clash.

Once the precedence was set ... ?

Cheers, T i m



--
Please do not look into laser with remaining eye.
  #18   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default Tandems with two sets of gears?

On Mon, 12 Jun 2017 17:32:50 +0100, "James Wilkinson Sword"
wrote:

If you do a google image search (sorry Brian), all the results have the pedals nowhere near each other.


Quite, they are all about as far away from each other as the length
between the bottom brackets will allow with the pedals in sync.

I would have thought if they were close enough to touch, the two riders would be uncomfortably close together (or comfortably if they were naked).


And they used to be like that and even today on my fairly modern
tandem, if the pedals were 180 degrees out of sync and with both
riders with feet as large as mine, they would nearly touch and could
easily touch if you were getting you feet in / out of traps whilst
pedaling.

Cheers, T i m
  #19   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 3,712
Default Tandems with two sets of gears?

On Mon, 12 Jun 2017 18:13:40 +0100, T i m wrote:

On Mon, 12 Jun 2017 17:32:50 +0100, "James Wilkinson Sword"
wrote:

If you do a google image search (sorry Brian), all the results have the pedals nowhere near each other.


Quite, they are all about as far away from each other as the length
between the bottom brackets will allow with the pedals in sync.


I don't understand that sentence. Did you say something in reverse?

I would have thought if they were close enough to touch, the two riders would be uncomfortably close together (or comfortably if they were naked).


And they used to be like that and even today on my fairly modern
tandem, if the pedals were 180 degrees out of sync and with both
riders with feet as large as mine, they would nearly touch and could
easily touch if you were getting you feet in / out of traps whilst
pedaling.


I've never known a tandem like that. Do you have a picture or a link to that model?

--
"All you need is love, money, broadband, good health, satellite TV, a fast car, ......." - The Beatles
  #20   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default Tandems with two sets of gears?

On Mon, 12 Jun 2017 18:33:55 +0100, "James Wilkinson Sword"
wrote:

On Mon, 12 Jun 2017 18:13:40 +0100, T i m wrote:

On Mon, 12 Jun 2017 17:32:50 +0100, "James Wilkinson Sword"
wrote:

If you do a google image search (sorry Brian), all the results have the pedals nowhere near each other.


Quite, they are all about as far away from each other as the length
between the bottom brackets will allow with the pedals in sync.


I don't understand that sentence. Did you say something in reverse?


Nope. Basically I was saying that if you rotated one crank 180 Degrees
to be as you suggested, the rider and stokers feet would probably
clash at some point.

I would have thought if they were close enough to touch, the two riders would be uncomfortably close together (or comfortably if they were naked).


And they used to be like that and even today on my fairly modern
tandem, if the pedals were 180 degrees out of sync and with both
riders with feet as large as mine, they would nearly touch and could
easily touch if you were getting you feet in / out of traps whilst
pedaling.


I've never known a tandem like that.


Like what?

Do you have a picture or a link to that model?


This is a classic example (not us or our tandem).

http://www.mark-ju.net/tandem/images/tandem1.jpg

Imagine the riders right foot at the 9 o'clock position, her heel
could easily be on the middle of the 'o' of 'Thorn' and if the stokers
foot was at the 3 o'clock at the same time, that could easily be
halfway over the 'h'. Put traps on those pedals and if she was pulling
her foot out backwards whilst they were pedaling ...

Cheers, T i m



  #21   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 2,454
Default Tandems with two sets of gears?

T i m wrote:
On Mon, 12 Jun 2017 18:33:55 +0100, "James Wilkinson Sword"
wrote:

On Mon, 12 Jun 2017 18:13:40 +0100, T i m wrote:

On Mon, 12 Jun 2017 17:32:50 +0100, "James Wilkinson Sword"
wrote:

If you do a google image search (sorry Brian), all the results
have the pedals nowhere near each other.

Quite, they are all about as far away from each other as the length
between the bottom brackets will allow with the pedals in sync.


I don't understand that sentence. Did you say something in reverse?


Nope. Basically I was saying that if you rotated one crank 180 Degrees
to be as you suggested, the rider and stokers feet would probably
clash at some point.

I would have thought if they were close enough to touch, the two
riders would be uncomfortably close together (or comfortably if
they were naked).

And they used to be like that and even today on my fairly modern
tandem, if the pedals were 180 degrees out of sync and with both
riders with feet as large as mine, they would nearly touch and could
easily touch if you were getting you feet in / out of traps whilst
pedaling.


I've never known a tandem like that.


Like what?

Do you have a picture or a link to that model?


This is a classic example (not us or our tandem).

http://www.mark-ju.net/tandem/images/tandem1.jpg

Imagine the riders right foot at the 9 o'clock position, her heel
could easily be on the middle of the 'o' of 'Thorn' and if the stokers
foot was at the 3 o'clock at the same time, that could easily be
halfway over the 'h'. Put traps on those pedals and if she was pulling
her foot out backwards whilst they were pedaling ...

Cheers, T i m


You must know that you are feeding PHucker.


  #22   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default Tandems with two sets of gears?

On Mon, 12 Jun 2017 19:38:10 +0100, "Mr Pounder Esquire"
wrote:

snip

Imagine the riders right foot at the 9 o'clock position, her heel
could easily be on the middle of the 'o' of 'Thorn' and if the stokers
foot was at the 3 o'clock at the same time, that could easily be
halfway over the 'h'. Put traps on those pedals and if she was pulling
her foot out backwards whilst they were pedaling ...


You must know that you are feeding PHucker.

I do, but everyone should get a chance to behave normally now and
again. ;-)

Cheers, T i m
  #23   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 3,712
Default Tandems with two sets of gears?

On Mon, 12 Jun 2017 19:14:26 +0100, T i m wrote:

On Mon, 12 Jun 2017 18:33:55 +0100, "James Wilkinson Sword"
wrote:

On Mon, 12 Jun 2017 18:13:40 +0100, T i m wrote:

On Mon, 12 Jun 2017 17:32:50 +0100, "James Wilkinson Sword"
wrote:

If you do a google image search (sorry Brian), all the results have the pedals nowhere near each other.

Quite, they are all about as far away from each other as the length
between the bottom brackets will allow with the pedals in sync.


I don't understand that sentence. Did you say something in reverse?


Nope. Basically I was saying that if you rotated one crank 180 Degrees
to be as you suggested, the rider and stokers feet would probably
clash at some point.


You said "as far away as the brackets will allow" which would be a very long distance. Didn't you mean as close as they could be without touching the pedals in sync? And the pictures to me look like 180 degrees out of sync would still leave a gap of about a foot (12 inches not a cyclist's foot).

I would have thought if they were close enough to touch, the two riders would be uncomfortably close together (or comfortably if they were naked).

And they used to be like that and even today on my fairly modern
tandem, if the pedals were 180 degrees out of sync and with both
riders with feet as large as mine, they would nearly touch and could
easily touch if you were getting you feet in / out of traps whilst
pedaling.


I've never known a tandem like that.


Like what?


That close.

Do you have a picture or a link to that model?


This is a classic example (not us or our tandem).

http://www.mark-ju.net/tandem/images/tandem1.jpg

Imagine the riders right foot at the 9 o'clock position, her heel
could easily be on the middle of the 'o' of 'Thorn' and if the stokers
foot was at the 3 o'clock at the same time, that could easily be
halfway over the 'h'. Put traps on those pedals and if she was pulling
her foot out backwards whilst they were pedaling ...


They should miss with a 6 inch gap as long as nobody's foot comes off.

Also, interesting foot position, I always put the pedal into the arch of my foot, all the power comes from my upper legs, not pivoting at the ankle.

--
Brazil nuts are an STD. If you eat a Brazil nut then have sex with someone who has nut allergies, they will have an allergic reaction.
  #24   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 13,431
Default Tandems with two sets of gears?

On Mon, 12 Jun 2017 19:57:45 +0100, "James Wilkinson Sword"
wrote:

snip
Quite, they are all about as far away from each other as the length
between the bottom brackets will allow with the pedals in sync.

I don't understand that sentence. Did you say something in reverse?


Nope. Basically I was saying that if you rotated one crank 180 Degrees
to be as you suggested, the rider and stokers feet would probably
clash at some point.


You said "as far away as the brackets will allow" which would be a very long distance.


No, it will be the size of the frame.

Didn't you mean as close as they could be without touching the pedals in sync?


No, it would be dependant on the size of a frame.

And the pictures to me look like 180 degrees out of sync would still leave a gap of about a foot (12 inches not a cyclist's foot).


Ok. I have a tandem, I have a foot (or two), I've measured both and
told you what I *measured*. So, what you think it looks like is of no
consequence.

I would have thought if they were close enough to touch, the two riders would be uncomfortably close together (or comfortably if they were naked).

And they used to be like that and even today on my fairly modern
tandem, if the pedals were 180 degrees out of sync and with both
riders with feet as large as mine, they would nearly touch and could
easily touch if you were getting you feet in / out of traps whilst
pedaling.

I've never known a tandem like that.


Like what?


That close.

So you can't see the pictures properly then?

Do you have a picture or a link to that model?


This is a classic example (not us or our tandem).

http://www.mark-ju.net/tandem/images/tandem1.jpg

Imagine the riders right foot at the 9 o'clock position, her heel
could easily be on the middle of the 'o' of 'Thorn' and if the stokers
foot was at the 3 o'clock at the same time, that could easily be
halfway over the 'h'. Put traps on those pedals and if she was pulling
her foot out backwards whilst they were pedaling ...


They should miss with a 6 inch gap as long as nobody's foot comes off.


Nope. Measure it up accurately and you will see you are wrong.

Also, interesting foot position, I always put the pedal into the arch of my foot, all the power comes from my upper legs, not pivoting at the ankle.


And that's why you are asking the stupid questions.

Cheers, T i m

  #25   Report Post  
Posted to uk.d-i-y
external usenet poster
 
Posts: 3,712
Default Tandems with two sets of gears?

On Mon, 12 Jun 2017 21:12:28 +0100, T i m wrote:

On Mon, 12 Jun 2017 19:57:45 +0100, "James Wilkinson Sword"
wrote:

snip
Quite, they are all about as far away from each other as the length
between the bottom brackets will allow with the pedals in sync.

I don't understand that sentence. Did you say something in reverse?

Nope. Basically I was saying that if you rotated one crank 180 Degrees
to be as you suggested, the rider and stokers feet would probably
clash at some point.


You said "as far away as the brackets will allow" which would be a very long distance.


No, it will be the size of the frame.


Which can be any size. But the pedals will be precisely frame size apart. So the allow part doesn't make sense.

Didn't you mean as close as they could be without touching the pedals in sync?


No, it would be dependant on the size of a frame.

And the pictures to me look like 180 degrees out of sync would still leave a gap of about a foot (12 inches not a cyclist's foot).


Ok. I have a tandem, I have a foot (or two), I've measured both and
told you what I *measured*. So, what you think it looks like is of no
consequence.


I've seen the photo you showed me, their feet wouldn't touch.

I would have thought if they were close enough to touch, the two riders would be uncomfortably close together (or comfortably if they were naked).

And they used to be like that and even today on my fairly modern
tandem, if the pedals were 180 degrees out of sync and with both
riders with feet as large as mine, they would nearly touch and could
easily touch if you were getting you feet in / out of traps whilst
pedaling.

I've never known a tandem like that.

Like what?


That close.

So you can't see the pictures properly then?


Yes I can, it's you hat's seeing them wrong.

Do you have a picture or a link to that model?

This is a classic example (not us or our tandem).

http://www.mark-ju.net/tandem/images/tandem1.jpg

Imagine the riders right foot at the 9 o'clock position, her heel
could easily be on the middle of the 'o' of 'Thorn' and if the stokers
foot was at the 3 o'clock at the same time, that could easily be
halfway over the 'h'. Put traps on those pedals and if she was pulling
her foot out backwards whilst they were pedaling ...


They should miss with a 6 inch gap as long as nobody's foot comes off.


Nope. Measure it up accurately and you will see you are wrong.


You even agreed with me by telling me the letter they'd line up with, so they'd miss.

Also, interesting foot position, I always put the pedal into the arch of my foot, all the power comes from my upper legs, not pivoting at the ankle.


And that's why you are asking the stupid questions.


No, that's why my foot doesn't slip off the pedal.

--
Why is Bin Laden like a pair of tights?
Because he irritates bush!
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Tandems with two sets of gears? James Wilkinson Sword[_4_] Home Repair 2 June 11th 17 03:12 PM
O.T. Tandems and how you pedal them Murmansk UK diy 6 August 18th 13 10:22 AM
03/17/07 Reuters: Two bodies found in Mosul: The bodies of two men and two women were found in various districts of Mosul on Friday. Two infants were found alive beside the two dead women, police said. BGKM Woodworking 0 March 17th 07 08:14 PM
Swap? Atlas 10F change gears, need 618 gears Rex B Metalworking 6 February 15th 06 03:41 AM
Wooden gears to metal gears. Don Stauffer Metalworking 5 January 30th 06 09:53 PM


All times are GMT +1. The time now is 04:37 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"