Starter motor E-Bike

[MetroMPG]

Originally Posted by WannabeEVer

anyone know where to find cheap atv or motorcycle batteries?

You can probably also get cheap or free SLA batteries from alarm companies. They replace them when they're down to 80% capacity.

Know anyone at the local hospital? A lot of their electronic equipment has battery backup that gets replaced often as well (so I'm told).

[almightybmw]

Question: The last starter I played with the starter gear pops out via a solenoid to engage, and withdraws when the power is cut. Couldn't you use that with a friction wheel to work instead of an armature to lift the whole assembly? This may have only applied to a certain starter I had (no idea what it was though), but I thought it was a universal thing. I have a super beefy V8 starter at home I'd like to play with, weighs about 25lbs (holy crap heavy). I'm really curious what a low amperage would do for longevity's sake. Batteries should be easy to come by, there's a few (SLA) sitting on the back desk for at least 5 months now.

[Ryland]

air plane starters tend to be built better then car starters, I'm not sure why it would be ok for a car starter to fail but not ok for an air plane to fail... maybe it has to do with being in the air and peoples fear of heights.
I wouldn't choose a car starter because I like things to last, I've put 1000's of miles on electric bicycles and never had one brake down on me, I like to keep it that way.

[Christ]

Originally Posted by almightybmw

Question: The last starter I played with the starter gear pops out via a solenoid to engage, and withdraws when the power is cut. Couldn't you use that with a friction wheel to work instead of an armature to lift the whole assembly? This may have only applied to a certain starter I had (no idea what it was though), but I thought it was a universal thing. I have a super beefy V8 starter at home I'd like to play with, weighs about 25lbs (holy crap heavy). I'm really curious what a low amperage would do for longevity's sake. Batteries should be easy to come by, there's a few (SLA) sitting on the back desk for at least 5 months now.

I've seen only very few starters that don't work this way, b/c once they've stopped applying torque to the flywheel, they disengage so as not to be damaged by engine speed.

If you've ever had a starter "stick" to the flywheel, it makes a horrible whining noise as the engine spins up to idle.

[WannabeEVer]

Alright, sorry about the delay on the updates for this but I've got the roller in, i just knurled a piece of metal, drilled a hole in the centre just a little smaller than the end of the sprocket, then heated up the knurled piece, froze the sprocket and they fit perfectly. I put a couple tack welds on just to make sure nothing would come loose. Talking about the solenoid thing, on the starter i have there's actually a separate power connection for the actual motor to the solenoid. So normally the power would go into the solenoid, then to the motor then back out, but if i just disconnect the solenoid part then it should be all good. Now I've just gotta go shopping for my electrical stuff and if everything works well I've got myself an electric bike.

[almightybmw]

awesome. Post up pictures of the setup when you can. Wish I had more free time to mess with the spare starter I've got. I'd love to begin biking to work again.

[order99]

Wish I had more time AND money.

Looks like you may be the first of us to finish-don't forget the pictures!

[rob_fed]

Originally Posted by Ryland

starter motors are designed to only run for a few hours total in their life and only for up to 10 seconds at a time or they tend to overheat, look at the size of them, they are around 2 horse power and the size of a quart jar, the 2 horse power continues use motor that is in my garage is about the size of a water melon.
starter motors also tend to have very small soft copper brushes, instead of the larger carbon brushes, they can handle more current but they tend to wear really fast, but if the motor only needs to last a few hours then that's ok.

I made this in 1999: "www".evalbum.com/251

For the most part, when a gear reduction starter motor is designed for intermittent use, not continuous duty. But a GR motor can be modified to allow for more continuous use. My nephew rode this go cart for over an hour, the motor was hot and the 90amp Hawker battery was down to 10.5 volts. But with many, many hours of use, I never have had to change any of the brushes (incidentally, most starter motor brushes are carbon based). Also, this motor was not brand new to start with, it was 15 years old from the auto wrecking yard.

[rob_fed]

Take away the quotes in the www, I had to add them because this is my first post on this forum.