Homemade starter

[brendonv]

Skip to about 7mins.

http://www.youtube.com/watch?v=n_mQjlUwYmI

Never thought of that lol. I got a lil 2 arm puller in the shed somewhere. Ill have to go fish it out.

 

[Cam]

Hey brendon, what about if you got a flexplate off an automatic? they are about 3mm thick and are made for the job - they are not a flywheel they are bolted to automatic torque converters, ill show ya what u mean -

why not bolt that on to your flywheel?

I just think its going to be way too hard to get that cog off and to put a chain drive in there, why not use it how it was designed?

My 2c
Cheers cam

 

[oscaryu1]

Heavy as hell, and I doubt he wants a 2 foot diameter plate rotating with his motor.

 

[Cam]

They are not that heavy, and you can get small ones for little automatics.

 

[brendonv]

Mounting it is the problem. I would have to make up a flange with a keyway. All equals money. Ill take my motor to my dads mate n see if he can get the bearing off for me. My puller wont do it. Its only a piddly lil thing. A sprocket or pulley is about 2-5 bucks so its a lot cheaper than a $70-$100 machined flange.

 

[brendonv]

how much hp does it take to turn over a starter motor? Mines going to be constantly turning so i dont want it to steal to much power.

 

[Cam]

Hey i found this in the shed, its a one way hub off a bike, sits out about 20mm, if you had one of these mounted somewhere it wouldn't need to be constantly turning, and it has a bike chain sprocket on it for mounting, no idea on how hard it is to turn a starter i wouldn't think they were designed for it however:

http://img69.imageshack.us/img69/8218/p1040132.jpg

http://img641.imageshack.us/img641/3010/p1040133.jpg

http://img687.imageshack.us/img687/6261/p1040130g.jpg

If you mounted that on your motor or flywheel do you think it would be better than having the motor rotating?

Cheers Cam.

 

[brendonv]

hrmm, dunno how it would go spinning at 5000rpm. Also the pitch of the sprocket is no good. I was thinking that i could hook up a voltage regulator to the starter motor so when it isnt powering the motor its instead working as a generator and putting power back to the battery or something for lights.

 

[Kaptain Krunch]

I dont know if you would even be able to generate power with a starter, arent most not even permanent magnet? I dont think its worth it...and honestly if you dont have the strength to pull over a 7hp robin...

 

[brendonv]

I have the strength i would just rather not have to do it. Its just cool to start it with a key i think.

 

[Cam]

Well that's what i meant Krunch, if it isn't putting any power out and is slowing down the engine then don't have it running! , im using one of those one ways on my kick starter, i had it apart they are very simple they are for back bike hubs, they will handle high speed, just pack em with grease!..

effectively it would work like a car starter, engage start disengage.

Your choice, cheers Cam.

 

[EagleTalons]

Have you see this yet? http://microbusa.synthasite.com/march-2009.php

 

[Cam]

When you go to start an engine that is not bolted on always kneel on it rather than stand, if you stand on it, when you go to pull you pull your weight off the motor making it bounce off the compression and kick out , i can start a 9hp Lifan kneeling on it, but standing on it, it wants to bounce and kick out, Cheers.

 

[brendonv]

Have you see this yet? http://microbusa.synthasite.com/march-2009.php

I have seen the videos but never the starter. His explanation is very brief, anyone care to explain in better detail?. I have a bike wheel in the shed (actually i got like 5) that i could rip apart. Seems like a good idea and a lot cheaper since i already got bike sprockets and chain.

Went to the bearing shop today and he has the pulleys i need. The engine pulley, the smallest i can get is around 56mm, which is around 8 bucks. The axle pulley which is about 300mm is about 30-35 bucks. So i need an idler pulley as well so in total including belt im looking at about 50 bucks in pulleys and dunno how much a belt is, say 15-20 bucks for a belt so about 70 bucks in total. A lot more than i expected but o well. Ill have double the power i got now and a clutch.

 

[brendonv]

Alrighty so i got an old wheel out of the shed and cut all the spokes off with some tin snips. Now i got the cassette and the hub. Im going to cut the hub in half and weld a big plate to it. Then ill weld the plate to the pull start on the engine. That way i can still use the manual pull start and i can cut the sprocket off the pulley if i take the engine off the kart later on. Ill also rip the internals out of the hub so i got a big hole through the middle so i can still access the bolt to remove the flywheel.

The tricky part of all this is getting it welded spot on so the sprocket doesnt wobble. Ill just tack it on, check check check check check then tack a bit more, check check check then weld. The good part about this is it freewheels afterwards so the engine wont be loosing any power.

Ill get all my pulleys tomorrow and ill get started on that maybe this week.

Should have this thing all on the kart within a month.

 

[brendonv]

http://www.youtube.com/watch?v=jNG9XdujMrg

 

[anderkart]

Looking good man.

Hey did you ever test your starter to make sure it spins in the direction your going to need here?

 

[anderkart]

If your starter spins the wrong direction you can mod it to run the other way. You'll just need to extend 1 or both of the wires attached to your brushes so they'll be long enough to reach around and be installed in the opposite sides brush holder. Just make sure you electrical tape the brush wires really well so they cant short out against anything.