On Wed, 29 Jul 2015 23:24:58 +0000 (UTC), John Doe
wrote:

Took it out in sunny afternoon 98°F weather for a 6 mile trip. The 20V
5AH battery shows one out of three bars remaining. Drill got hot but
there was no performance change.

This is really interesting, but I'm having trouble with some of the
numbers. Say the "two bars" consumption equals, roughly, 3 A-hr. At 20
volts, we have 60 W-hr. Just guessing here, but say you travelled that
6 miles at 12 mph.

That means the drill was drawing an average of 120 W for a half-hour.
Let's be generous and say that the system efficiency is 80% from
storage to power at the drill shaft. So, given chain and friction
losses at the tire, you have 1/8 hp driving the bike.

Will that be enough to move you at 12 mph? I'm not familiar with the
actual power consumed by these bikes, but that sounds low. Am I
missing something?

--
Ed Huntress






First made a push stick for in-line skating...

https://farm6.staticflickr.com/5270/...79e62d61_z.jpg

Got a little real-world use out of it. It was fun. Eventually the
right angle gear broke from normal wear and tear. Having no support on
the other side of the wheel, that was no surprise.

That did not take advantage of a clutch, mainly because there is no
clutch on DeWalt's right angle drill. Stopped skating. Started
cycling. Now I get to take advantage of all the cool stuff that a
cordless drill includes, including the clutch...

https://farm4.staticflickr.com/3681/...deaab67a_c.jpg

https://farm1.staticflickr.com/538/1...d07dec60_c.jpg

Apparently the drivetrain has loosened up a bit. Using the highest
clutch setting (before drilling) worked fine for going up slight hills
today. The clutch only slipped once, when I was at a stop and
accidentally slapped down on the throttle. Worked just like it's
supposed to.

Bought some aluminum and plastic suitable for rebuilding the sprockets
without wood. I might try to eliminate all the wood in the structure,
but wood is useful for making unplanned additions. Or maybe I will try
using thick PVC slabs. It's lighter than aluminum.

Also want to upgrade the drill to one that includes a soft start
feature. The soft start sounds cool for more smoothly powering a
bicycle. It might not be necessary, but I'm sure it's better.