That would probably be best, sounds like the old mech. speed controls.

Jeff

Using just the servo tester for the throttle, I am pretty sure I am geared too high. Minimum throttle is probably 10 mph. Got a broken pin and some good, long squeals from my motor too. I'll look into gearing down with new gears...

What would I need, 3/16, #35 roller chain? Where do I get sprockets? Could I weld a gear onto the freewheel after cutting the stock plastic pos off?

Mcmastercarr.com

You can get Sprockets from a local industrial salvage yard. Yea you can weld a sprocket to the freewheel. You can also try sprockets for #25 chain, will be easier to get the reduction you need...

Looking around I found a 90t #25 sprocket ($20) I can use with my 13t "pinion", or I can get a "pinion" from mcmaster car with set screws ($5)... Chain will cost me $10 from mcmaster, I need probably 2.5-3'. It would be nice to get all three Items ($35). I'm working 16 hours this weekend so I could get this stuff as a reward...

I found a 5k ohm sliding pot that could be hooked up into a throttle pretty easily. Just put a small rubber band on it (gluing the ends) to return the throttle to neutral and I'm set..

http://www.electricscooterparts.com/images5/POT-5KS.jpg

Can you give me an example of an "industrial salvage yard"? I live by a city of 200k and there's nothing even close to that around here... jesus it's probably 400 miles to a place like minneapolis or Kansas city. :angel:

Got a link to this sliding pot? I get alot of entertainment out of electrifing/motorizing things, so I'll probably so a lot of these conversions, and that would come in handy. Oh also, nice find on the #25 stuff! The place I went to doesn't have a website, but it is basically a place that buys stuff from industrial companies that are going out of biz usually, with a old guy behind the counter, where you just go, pick out what you need out of piles and shelves of crap, and the guy gives ya a price (usually real cheap) and you walk outta there..

There's a tool place kinda like that around here... But the stuff isn't strewn about and the prices aren't quite as low.:eyes:

The 90t sprocket I found at monster scooter parts - http://www.monsterscooterparts.com/9...-scooters.html

I found the pot at electric scooter parts .com under the throttles section - http://www.electricscooterparts.com/throttles.html

they also have the 90t sprocket but it's $10 more. Everything is a little more expensive here then at other places. I'd go with mcmaster for everything, but they don't have the 90t sprocket.

I'll take the wheel to a bike place and see if they can screw off the old freewheel. I have anoter freewheel I can bolt a sprocket on off of another scooter. It has a 72t #25 sprocket, but I'll need a little bigger one. Want to gear for about 20-25mph on 24v, and the 72/11 combo I have now will get me 27mph, too much.

New Plan
I can get a 9t sprocket from mcmaster carr, use my 72t sprocket, and add some chain to the mix and then I'll have saved $20 on the 90t sprocket. How much do you think a machinist would charge to machine a 1/4" hole to a 10mm hole?

sprocket is part number 6793K1 and chain is part number 6261K283. McMaster Link is 6261K108

What pitch is your 72t sprocket?

#25, 1/4". It's from an old electric scooter. I sent an email to a couple machine shops getting quotes for modding a sprocket.

Cool. Is the shaft on your motor 1/4" though?

Assuming your motor has a 8mm shaft, you can get this sprocket:
https://sdp-si.com/eStore/PartDetail...63&GroupID=649

My shaft is 10mm. The #25 sprocket from on old scooter I had has the same shaft, so it must be pretty common in china.

http://www.hobbycity.com/hobbycity/s...idProduct=5144 - This is supposed to be my motor, but it looks longer and has some screws in the bell now. The shaft might be 12mm on the newer ones... But mine is 10mm.

OMG. I test drove it today. You have to be rolling at 2-5mph depending on battery charge to make sure the motor doesn't lose sync at start up. That's one of the problems of being overgeared...

The brakes didn't do much. They are crap because if I tighten them any more they rub a little...

Once you got going, it was a great ride. First, top speed was 10-15 mph. My friend could sprint beside me. We charged up the battery for an hour and a half, and top speed was MUCH higher. Probably 25+. It's faster then it sounds on a little bike like this, especially with no brakes. I'm charging the battery right now, and I'll see if I can try it out tomorrow with a full charge. That will be fast.

Temps were averaging 90-105 on the motor/controller and about 90 on the battery. I don't think I'll be running 36v on this motor any time soon.

I am still planning the #25 chain conversion. I'll re-do the rear wheel so that will be smoother, and replace the off-centered pinion. The belt is already showing signs of wear and the whole setup is iffy. The chain will be nice... Can't wait.

I'll post up a video once I get a chance to open it up will full batteries. That might be tomorrow, monday, or tuesday.

And Ian, I hope the detta comes tomorrow; didn't get it today.

NICE! You got it running. About the detta- I wasn't able to get to the post office till the day after I said I would. Sorry about that- it should come today.

Hey that's fine, I got it today. A good gift after getting up 4 hours early and working 8 hours.:sleep:

I will order the gear and chain from mcmaster soon. Then it should be a really tight bike.:intello:

Now just get yours done and we can compare them. :whip:

Well, yours is 10mm, so hopefully his will be larger... :rofl: