I Need a clutch

S

SpiderSpartan

New Member
Does anyone know where I can get a clutch for my weed eater bike project. I know basically nothing about clutches and how they work, except that when the engine speeds up they engage and spin the sprocket. Anyway, if you have any idea where I could get one I'd appreciate a tip. Thanks.
 
I would say find out what brand you have and that will give your answer to were to start looking, anway thats what I would do, Im sure some one in the fourm will give you the answer your probably looking for, maybe post a pic of it
 
First of all I don't use the clutch parts from my weed eater when I build. So this may be all wrong but here goes.

The clutch consists of the bell, that is the outter part that you can see. Then underneath that is a mechanizm threaded onto the shaft of the motor. When he motor reaches a certain speed the mechanism spreads out to engage the bell and spins it. I think that is pretty much how a centrifugal clutch works.

So what parts do you have? Do you need it all or do you just need a different bell with a different kind of end on it. Since I don't know where you could get either I'm not going to be of much help to be honest.
 
I'm pretty sure the one I have has no clutch at all on it. So I would need the whole thing. Here's some picks. The crank shaft is broke, so I'll need to replace that too.
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I didn't see the pics but frankly if all that is bad I would just move to a different motor. There are plenty of them out there. It probably would be cheaper in the long run.

Around here you can get a used one that runs for about 35 bucks on craigs list. Ebay is full of them but I would go local and hear it run. You can even get new ones for seventy five dollars at lowe's or home depot.

at that price they probably don't have clutches though. The used ones probably would though. You would just have to ask.
 
You could make a manual clutch, just a loose V belt and 3 pulleys. When you tighten the belt with one pulley the engine spins the other one. Its been working for years on my minibike and should work for a weed eater.
 
I Found a centrifugal clutch here. Ends up being just under $35 after shipping. It has an 11 tooth sprocket attached. There's a couple 60 tooth sprockets on that site too for about $10. I figure that the drive shaft will spin about 8000 RPMs. That being the case using a 12/60 gear ration should give me a top speed of about 30MPH. Shipping stays the same so these two items would run me just under $45 from here. I'll keep looking for now. If anyone could point me to a cheaper place that would be awesome thanks.
 
That clutch is way too big. A weed eater has a 5/16" to 3/8" shaft. Nothing like a 5/8" shaft.

I would look for a motor scooter clutch. Like this Clutch Bell Housing Gear Box - 6 Tooth Sprocket

It may be for a 47-49 cc engine but it has a smaller shaft. Something closer to yours, this way you can slide a piece of pipe that fits over the weed eater shaft to fit the scooter clutch.

Its also pretty cheap. I have one of these scooters, they use some very small chain.
 
Thanks Ranger! That looks awesome. Do you think that #25 chain would work for a bike though? I was planning on using #35 chain. How hard would it be to put a #35 sprocket on this thing? Thanks again.
 
If im not mistake a 35 chain is for scooters and is very small. I think that is what I used on the scooter tire I used for a friction drive. I had a bushing inside the 1/2 sprocket to get it down to 5/16 It worked okay by the way but no better than a pipe on the wheel.
 
Wikipedia on Roller Chains:
The first digit(s) indicate the pitch of the chain in eighths of an inch, with the last digit being 0 for standard chain, 1 for lightweight chain, and 5 for bushed chain with no rollers. Thus, a bicycle chain with half inch pitch would be a #40 while a #160 sprocket would have teeth spaced 2 inches apart, etc.

This site explains some about sizes. It doesn't have 25 on there, but it discusses the difference between #35 and 40's chain.
As far as the clutch goes, I'm not sure what to do yet. I'm leaning toward getting the bigger clutch off ebay just cause I don't want to have to worry about buying a new chain and sprocket if I can help it.
Thanks for all the input guys.(^)
 
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