bicycle engine clutch.

[MeatCarcass]

but I cant get the chain gear cover that holds the clutch arm to sit flush on the engine. There is atleast an 8th inch gap because that pin is sticking out too much. Am I supposed to just force it on there?

 

[GearNut]

If you can get the sprocket cover screws to thread into the case at least 3/8 of an inch, remove the screws and oil the threads of the screws to help prevent damaging the threads in the case. Now you should be able to tighten each screw a little at a time, pushing the cover on evenly, until it is on all the way. After that is done, adjust the clutch as previously stated.

 

[MeatCarcass]

i got it on, its a tight fit and the clutch arm barely moves. It takes quite a bit of force to pull the clutch cable, but it seems to be working like its supposed to. but there is alot of resistance trying to pedal when disengaged, I'm gonna try to straighten the tension thing or the drive sprocket on the wheel to see if that helps.

 

[GearNut]

Re adjust the clutch. The bike should be pretty easy (relatively speaking) to pedal when the clutch is disengaged/ lever pulled in.

As for how hard it is to pull the lever in, they all are stiff when brand new. It will get easier to work as the engine gets broken in.
Lubing the cable with a quality lube, making sure that there are no sharp bends or kinks in the cable routing along the bike, grinding the very edge off of the release cam, and the pulley mod all make the clutch easier to work.
My engine has 500 or so miles on it. I can pull my clutch in with one finger. All I did was use a teflon lined bicycle brake cable and grind the edge on the cam. Pulley mod will be had later.

 

[MeatCarcass]

its still rediculously hard to pedal, its also makes this weird grinding noise and I can hear the pressure plate ringing at the same time. I read somthing in the manual about grinding down the teeth on the drive gear (the small one on the engine.) Do you think that might be causing it? The teeth on that gear seem to be more square than round...

 

[GearNut]

If the drive chain has difficulty following around the sprocket due to the links getting caught on the tips of the teeth, then yes, file the tips accordingly. Sometimes they are a little too tall, other times they are a little to squared off and need the lead in ramps on their inboard and outboard faces smoothed out.
Also note that the factory chains are known for having stiff links and even twists in them.
Inspect the entire length of the chain for these issues.
The grinding noise could very well be the chain riding high on the engine sprocket and rubbing against the front of the sprocket cavity. This is actually common.
On my engine, I just cut the front edge of the sprocket cover a little to let the chain clear it.
These engines are not precision made like a Japanese motorcycle. They quickly show this fact when put to use.

 

[fm2200]

What is the typical life span of a clutch, I have 2 years on my 2 bikes.

 

[pechroc1]

i have the opposite problem. i cant... no matter what i do... get the damn thing to engage.....? no grease or dirty behind the clutch plate. and i have yet to get the damn thing to run! i hope someone knows what going on cuz i sure dont heres the deal:
i found a thread explaining all the adjustments that can be made to the clutch. even after all adjustments in many combos it wont grab.

i have a couple questions:
1- is it possible the piece of SH!T friction pads are shot without ever being run?
2- as tightening the flower nut it grabs better only until a certain point...then if i tighten it 1/8 of a turn more i lose all friction. DOES THAT MAKE SENSE? it seems as it should increase the friction until it locks. but it never locks. i really cant understand.

 

[GearNut]

Well, it could very well be the clutch pressure spring, the spring responsible for squeezing the friction pads tightly to the pressure plates, has been assembled too loose from the factory. Here's Norm's tutorial on adjusting it:
http://motorbicycling.com/f39/adjusting-clutchs-spring-more-tension-8392.html

I am also now wondering if perhaps the woodruff key that is supposed to lock the engine chain sprocket to the output shaft is missing/ left out from the factory?
Have you looked to see if the sprocket is spinning on the shaft? That would make it seem as though the clutch is slipping when in fact the sprocket key is the culprit.

 

[fm2200]

the small sprocket on the engine is probably the cause, as mentioned above by GearNut.

 

[pechroc1]

the small sprocket on the engine is probably the cause, as mentioned above by GearNut.

after adjusting and adjusting with no success and much frustration...i wound up fitting a washer between the clutch plate and the flower nut. worked like a charm. the only thing is that the clutch cable arm is pointing more towards the center of the frame... big whup! its seems after reading another post about the same issue this might be a new defect with some of these kits.

didn't realize that this little engine would be such an addiction. im very handy but this is my first motorized mechanical venture. very fun! thanks for all your input fellas.

p.s. ill post some pics soon for those who have the same issue and want to try this remedy.

 

[GearNut]

I am glad to hear that you got it all worked out!
I am familiar with the other post you are referring to.
Counting that post and now your experience, I have only heard of 2 accounts of this problem. I hope it does not become a trend with alot of the newer kits.

 

[MeatCarcass]

I think my clutch pucks are squealing against the pressure plate. I was recently talking to this other local guy that has a few motorized bikes of his own, he tells me that squealing is normal and will eventually go away. I have finally adjusted my clutch to where if i tighten another notch, the clutch wont disengage. when I loosen it 1 notch, it works like normal, but my clutch is still squealing. Is this squealing normal for those chinese engines?

 

[Jumpa]

[Left counter clo9cjkwise Id say it also sounds as if your "Flower nut" is either not doing its job or missing altogether?? Just my 2 ¢ . By the way nice art work easy to follow for us noobs Thank You for the time and effort Is there any way to get more out of your clutch someone told me to soak them in kerosene they will fatten up has anyone tried this? /B]

 

[GearNut]

The rubber in the friction pucks may very well react with the kerosene and swell up thicker, but do take into account that kerosene is also petroleum based and will act as a lubricant. The idea of slippery swollen pucks does not sound very good to me.
FWIW, kerosene makes for a very good lubricant when tapping new threads into aluminum.

 

[Jumpa]

Yes very good point Gearnut, I soaked them in Dawn and water to get the petrol. off. I nixed the kero method

 

[JIM4887]

Hi starting out of the box i put the thing together it would not roll clutrch in or out. I turn the flower nut to get it to roll but i can seem to get the motor going when im pedaling do any body knows whats wrong???

 

[JIM4887]

Hi starting out of the box i put the thing together it would not roll clutrch in or out. I turn the flower nut to get it to roll but i cant seem to get the motor going when im pedaling do any body knows whats wrong??? i smell gas on the plug. i can here the piston moving up and down.

 

[Jumpa]

take the cover off the sprocket and see if the chain is bound up ...that happened to me all it would do is skid down the road w/the clutch in or out http://motorbicycling.com/images/smilies/Waa.gif

 

[userix]

I am attempting to take out my clutch assembly, since there is problem with it binding and locking up randomly when rolling around with the clutch lever in (disengaged). I suspect something is broken inside where the clutch spring sits, because everything looks fine from the outside on both the small sprocket and clutch gear sides. I decided to practice taking out the clutch assembly on a busted engine I had from a previous build.

Through my experience, it was really difficult to drive out the clutch assembly from the chain sprocket side. I followed Norman's advice and didn't hammer on it from the clutch gear side in order to prevent damage to the clutch shaft pin. I had to hammer on the shaft pretty hard with a 4lb drilling hammer (badass mofo) against the flat sides of a box wrench to the shaft to finally drive the assembly out the clutch side.

It seems the bearings that sit on either side of the clutch assembly are fitted extremely tight to the engine casing. While I don't really care too much about this busted engine, I don't feel comfortable banging that hard on other engine I am going to fix. Would some PB blaster or penetrating oil on the bearings and clutch assembly shaft help in its removal? I want to minimize the blunt force trauma done to the engine, considering it will be done while still mounted to the bike frame.

Now this leads into the next problem: reinstalling the clutch assembly. Seeing how it was so difficult to remove the shaft, it will be equally difficult, if not harder, to put the bearing back in flush to the engine casing. I can only think of using a large deep socket placed against the bearing and hammering it back in place. But there is no way I can be certain I am hammering the bearing in straight and not cockeyed. Will hammering the bearing directly damage it? Is there a better way to approach this problem?

And my final question/problem is how to put back on the clutch gear and small chain sprocket? Do I screw in the gear puller and then use it as a hammering point to drive the sprocket and clutch gear back on the shaft? How do I I know how far in to go with the small sprocket? Will it stop at a certain point? Can I hammer the sprocket/clutch gear on just enough to get the locking nut on and instead tighten the nut to drive the sprocket/clutch gear back in place?