Jerky clutch

rohmell said:
Good Luck with your centrifugal clutch.
Yes, it's a real easy install.
Let me know how it goes and how you like it after you have used it on your MB for a coupla miles.
Click to expand...

I'll definitely report back and let you know how it goes, thanks again for your help.
 
Rohmell,

I receive the clutch today but can't figure out how to install it. I took out the clutch cover and do I take out the small gear? Please help.
 
rohmell said:
Yes, the centrifugal clutch takes the place of the small gear.

Here are instructions:
http://www.zoombicycles.com/downloads/addons.pdf
Click to expand...

I checked out two instructions and one didn't say anything about cutting off the clutch studs while zoom instruct to do so. If I take off the clutch adjust screw, there's a spring in the back that will push the clutch out. How will I cut the studs without the clutch falling out? Also, my engine didn't come with a gear puller, can I take out the gear without one?
 
First, see if the new clutch cover plate fits without hitting the clutch studs, if no hit, then you are OK, no need to cut anything, if hit, them just use a Dremel tool to cut the studs, no need to disassemble the clutch.

It is better if you leave the clutch assembled when cutting the studs, that way you don't cut the studs too short, they need to protrude a wee dab above the clutch disk.

The small gear is on a taper, so it will probably be very difficult or impossible to remove without damage, so get the puller tool, you will be glad that you did, it will come in handy pulling the gears if you ever want to disassemble the engine for maintenance or cleaning.
If you don't have a Dremel, get that as well, it is a very, very useful tool to have, if there is a Harbor Freight Tools store near you, they have this one it's on sale now:
Professional 4 Speed Rotary Tool Kit
Use a 20% off coupon and the price gets knocked down to $11.98!

Let me know how it goes.
 
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Thanks for the reply, I already have a Craftsman dremel tool that I can use to cut the studs if they hit the cover. Where can I get a gear puller? So basically take out the gear, install the new clutch and put the cover back on?
 
Yeah, I have the Craftsman version also, works very well.

Engine sprocket and Clutch Hub puller tool here:
ENGINE_KIT_PARTS_PAGE_4
Maybe other vendors have it as well, this one is the first place I looked.

Yes, remove the gear, and the clutch goes in its place. The clutch does not use the Woodruff key, it relies on the taper-fit-friction to hold together.
 
rohmell said:
Yeah, I have the Craftsman version also, works very well.

Engine sprocket and Clutch Hub puller tool here:
ENGINE_KIT_PARTS_PAGE_4
Maybe other vendors have it as well, this one is the first place I looked.

Yes, remove the gear, and the clutch goes in its place. The clutch does not use the Woodruff key, it relies on the taper-fit-friction to hold together.
Click to expand...

I was hoping to get one from a retail store somewhere instead of ordering one online. I don't want to wait a week just to get this installed. So insert the new clutch and tighten with the bolt that came with it? There's also 2 bolt that was in the package, what do I use those for?
 
It is such a specialized tool for a specialized piece of equipment, unfortunately it is not available locally. Consider it an investment, it will come in handy if you decide to continue building and using Motorized Bicycles.

One bolt goes thru the clutch and into the threads on the end on the crankshaft to hold it on.

The other bolt is a clutch puller/removal tool. There are two types, fat and skinny end. It threads onto the threads that are in the clutch hole and as you turn the bolt, the end of the bolt will press against the end of the crankshaft if it has the fat end, if it has the skinny end it will go into the crankshaft hole and press on the inside end of the crankshaft, and the clutch will move towards you and come off.

That's all that usually comes with my kits, sometimes an extra cover screw is thrown in, sometimes not.
 
I just ordered the gear puller, now I have to wait a few days to install the clutch this sucks! I was excited to install it when I got it yesterday.
 
Yes, I know how that is.

Some kits come with the clutch pulling tool, and others don't. Then you have to pay extra $ and wait for it when you need it.

But at least you can still ride your MB with the regular clutch, it's not like it's down for the count and inoperable
 
Oh Yeah, I’m planning on tearing it up around my neighborhood with the old clutch when I get home tonight. I was just eager to install the new one, I hate the fact I can’t cruise at a slow speed without engine jerking. In the meantime I guess I can spray paint the covers black since my engine is black. Silver cover wouldn’t look good on a black engine. Thank you so much for your help and I’ll let you know how it goes when I get that part and have the clutch installed.
 
I always paint the clutch, magneto ,drive gear covers and gas tank to match the color of the bicycle that it is mounted on.
I think it looks more 'professional' that way.
 
Here's a pic of one of my bike, it's a Raleigh C30 hybrid. This is the one I plan on installing the centrifugal clutch.
 

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Hey Rohmell,

My parts haven't came yet but I have a quick question, when I release the clutch and start the motor as usual, do I press the clutch and lock it to run the bike? Or do I just leave it alone? I'm not exactly sure how the old clutch can still be engage while the new clutch is engage.
 
You will release the clutch and start the motor as usual, then leave it alone (released). The centrifugal clutch will take over and do both engaging and disengaging automatically.

If you look at your centrifugal clutch,you can see the three black friction pads are retracted towards the center of the unit, away from the outer drum. When it spins fast,(acceleration) those pads will expand out and contact the drum and grip it to transfer power, and when you slow down, those pads go back toward the center and no power is transferred.

It's all automatic, based on your engine speed.
 
Understood, but what happens when I'm at a stand still with the engine still running, will the bike still roll smooth? This is the part I don't understand, the clutch is still engage so how can it roll smooth with the engine running? What happens if I'm running and I press the clutch? Back to the main subject, could it be that my clutch is slipping that's why it cause my clutch to jerk at low speed?
 
It will be like having two clutches in series, your old manual clutch, plus the new centrifugal clutch.

At a standstill with the engine running, the engine speed is too low, so the centrifugal clutch shoes are retracted, so no connection is made to the engine.
If you are running/riding (this means that the centrifugal clutch is engaged) and press the clutch, then it will work the same way as before.

Once you install it, everything will become more clear.

Yes, it could be a slipping clutch causing the jerk at low speeds.
 
Not to divert the topic away from the clutch, but I am wondering how smoothly your motor is running at these low speeds? When my carb wasn't tuned well the motor would run smooth at higher RPMs but ran rough at lower RPMs, this made my low speed riding very jerky, had nothing to do with the clutch. If the motor isn't running smoothly you can't expect the ride to be smooth, if the motor runs rough your ride will be rough. I think the momentum of the higher RPMs helps keep things smooth even if the motor is running a bit rough, when you slow it down a rough running motor translates to a jerky ride...
 
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