Hi. I couldn't find a thread on this, so I'm starting one of my own. I bought parts to build an engine from gasbike.net. I bought a crankcase with a centrifugal clutch and a top-end rebuild kit. I assembled the engine while a more knowledgeable buddy supervised. the engine does not have a necessity for a manual clutch as far as I can tell. In fact, there are screws where certain parts for the manual clutch would normally go. The problem is this. The cent clutch is always trying to grab and making a lot of noise. It not only makes a noise that concerns me when the engine is off, it makes it difficult to start as well. From what I understand, it requires some sort of maintenance or adjustment. I found instructions on a website called eHow explaining how to adjust it, but they didnt help. the instructions said to loosen the large nut holding the clutch on and move the adjuster screw that is behind the large nut. on my clutch, there is no adjuster screw, only a large nut. If anyone can give me accurate advice, i would appreciate it.
Need help with centrifugal clutch
- Thread starter bigbutterbean
- Start date
40 views of this page and not one attempt at an answer.....smh.....I hope at least one person is nice enough to offer me something here
It is a two stroke motor from gasbike.net. I think I understand why the instructions describe an adjustment screw. I saw a video on youtube of a centrifugal clutch, where the drum was on the outside of the clutch and the part with the spring and the weights was on the inside. if most cent clutches are assembled this way, that would make our clutches backwards, and eliminate the adjustment screw that is described. besides that, the instructions did not contain any pictures to show what they were talking about. pictures of my engine wont show the problem. its a noisy clutch and thats all. i think i may know what the problem is though.
after much research, I have discovered that these clutches are supposed to be one way. my bearing race moves both directions. from what I understand, there is a spring attached to the crankshaft which is supposed to connect to one of the holes on the inside of the drum. if that spring comes loose, it can cause the exact problem I am having. tomorrow I am going to take it apart and check to see if that spring has come loose.
I also know that several people on here have recommended or worked on keying the crankshaft for the automatic clutch, I have neither the tools nor the knowledge to do so, and dont know anyone that does. also, it doesnt sound like its easy to get it right on the first try. not a job for me, thats for sure.
I think its referring to go-kart and minibike clutches. i would assume those clutches would freewheel either direction (no need for them to be one way, because they aren't pop-started). Due to the fact that these chinese engines are supposed to be pull-start or pedal-start, they have to be one-way or they won't operate correctly. The requirement for the clutch to freewheel in only one direction changes the setup just a little bit.
If you have a Harbor Freight Tools store nearby, they have everything you need to do the job.
A rotary tool for $20 Professional 4 Speed Rotary Tool Kit
and a set of diamond coated drill bits for $5 4 Piece Diamond Coated Rotary Drill Bits
or even better, this set 20 Piece 1/8" Shank Diamond Point Set
Then you lay the bit against the centrifugal clutch where the gear is and try to duplicate the keyway like the small gear has. Your keyway will end up being round instead of square like the small gear, but works fine. There are pics of the finished modification to the clutch here on this forum.
You posted the 1st message at 10:59 PM, and this message at 2:09 AM.
Most people are asleep at this time, so that's why not so many views or answers.
If is is always trying to grab, then your idle is a wee bit too high. You hafta knock it down a little.
On the centrifugal clutches for the China Girls, the drum is on the outside and the weights are contained within.
I don't know what kinda clutch you have if you say it is backwards.
Yes, there is a sprag inside that allows the clutch to turn one way only. This is so that you can still start the engine the old-fashioned way by pedaling and popping the clutch.
If you have a pull-start installed, then you can use the clutch as it is.You will only be able to pull-start, and not pedal-start.
This drum issue may be beacause he can see the shoes(they are inside but not behind the drum)
ok so the part with the 3 shoes moves counter clockwise but not clockwise. is this how it should be?
so does that mean the clutch is operating correctly? if so, then why is it so noisy? today, it wont start at all. when i pull the pull start with the back wheel lifted up, the wheel moves when i pull the rope. it makes a whining noise like something is grabbing too hard and not letting the engine turn over. it makes the same noise when i roll the bike forwards or backwards.
The shoe's turn the same as the little gear ,counter clockwise,,,,for the noise,make sure the engine is turning at the time the bike is rolling and the manual clutch on the handlebar is "not" squeezed,,,,,remove the plug and make sure the sound is not in the piston part
