help centrifugal clutch

Cabinfever1977

New Member
i have a 48cc dual start starfire II grubee from gasbike net.
it has a friction clutch and a centrifugal clutch.
i like to use the auto centrifugal clutch as it idles lower at stop signs.
when im stoped and front brake applied using just the centrifugal clutch,the back wheel is tring to turn and jerk at idle.anybody know how to fix it so the back wheel doesnt move unless i pull the throttle.i already did lower and adjust the set screw.could it be inside the carb on cable spring clip postion?or something else?
 
I think your idle is still set too high or the shoes in the C. clutch would not be opening to engage the bell. Take the round cover off the C.clutch and see if you can rotate the bell with your hand with motor not running. It should rotate easy with no rubbing.( Some only go one way.) If it does not rotate the problem is in the clutch...POPS
 
Yep, idle is probably too high. Also, on two of my bikes, it took a while for clutch to bed in. For both of them, it took about 45 minutes of riding for the clutch to actually work as designed. WHen new, both of my clutches seemed to be engaged the entire time then viola, they worked as advertised. Don't know why, just an observation.
 
I think Cabinfever and I got our kits about the same time, very recently. There does not seem to be much info on the cent clutch on a 2 stroke. So I have a couple questions as well.

1. Should I be able to pedal the bike with the clutch engaged from a standing start
2. When I have the manual clutch pulled and let it out the cent clutch engages as I am pedalling to get the engine started and then release and will not engage until the bike slows to almost a stop.
3. What adjustments can be made?
4. I have the opposite problem when I stop, the engine dies. If I increase the idle, 1/2 turn then when the engine is warm it really races at idle, is this normal?

Should I just go on a long ride >30min tos see if that resolves issues?
 
i have the cover off,with the manual clutch pulled in,i can rotate the bell with no rubbing,so it must be the idle.
also when i have the engine running,i hear a scraping noise,and i found that the clutch bell was rubbing on the cover,there are a couple of high spots(little dings)on cover,i'll try to fix that.and i'll check into the idle problem.
 
i think i fixed the scraping noise,i wont know til i take her out for a ride,those clutch covers are thin and cheap.
my e-clip is on 2nd notch from top of needle inside carb on slide,up or down a notch to lower idle?
 
I am having some starting issues. I pedal and let out the manual clutch, the cent clutch engages for a sec and then releases. I have to slow to almost a stop before the clutch engages again. I pull in the clutch lever, stop the bike, and start pedaling again. I may have to do the a few times.

Does anyone know if there are any adjustments that can be made to the cent clutch

Could it be broken, I hope not since the vendor probably does not want to hear from me.
 
thats weird,i dont know how to fix that,im sure it just needs adjusting,are you sure you have a centrifugal clutch or a manual one or both?

i have a dual start with both and comes with pull start.mine works great.
 
I am having some starting issues. I pedal and let out the manual clutch, the cent clutch engages for a sec and then releases. I have to slow to almost a stop before the clutch engages again. I pull in the clutch lever, stop the bike, and start pedaling again. I may have to do the a few times.

Does anyone know if there are any adjustments that can be made to the cent clutch

Could it be broken, I hope not since the vendor probably does not want to hear from me.

Lordo
The C/clutch has nothing in it that is adjustable. It sounds to me that your main clutch may be slipping. Did you check the clutch plate for grease to see if there is any on the plate to cause it to slip or maybe even grease on the C/clutch shoes ? If so ,clean with brake clean and it should solve your problem...POPS
Let us know what you find.
 
Lordo
I think I got it. If it is not greese there is a spring that holds the bearing race to make the C/clutch only free wheel one way. This allows you to peddle start because it will lock up. If that spring(paper clip) thing is letting go and kicking back in ,theres your problem. Do you have pull start?Get back to us. POPS
 
POPS,

I hadn't checked on the grease thing. I was working on my other bike mostly yesterday.

Yes, I have a pull start for all the good it does me. I just don't have the arm strength to make it work. Others do, though so I know it works. Now where would this spring clip be?
 
Lordo

Take off your clutch cover(round one with 4 screws)

You will see clutch shoes,clutch bell and center bolt.

Have a helper hold the shoes while you crack(sharp blow)

the center bolt off ( anticlockwise).

The whole unit may come right off as an assembley.

If it does not thats OK. It is a tapered press fit on the crank.

Take 2 small screw drivers and wedge the shoes out of the clutch bell.

You will see the spring clip that is supposed to load the bearing race in one direction.

If it has moved or is loose that is the problem. It will then allow the bearing to freewheel

both ways with out the preload. The movement is not much at all. Can hardly see it.

While holding the clutch bell with one hand, Try to move the bearing race both ways.

To the rt. and lft. If you have movement there is the cause . It has to have a consistant

preload. Bend(move) the spring so it pre loads and re assemble. You should be good to go.

PS...All this should be done with your main clutch engauged...Hope this helps...POPS
 
This sounds like fun. A few questions.

Do you mean the cover over the centrifugal clutch? If so, they do provide a tool for removing the clutch. Getting the rest of the manual clutch cover off is a little bit more complicated.

Would this explain why it will work after I stop and rest a second a couple of times? When I do this are ball bearing going to run wild on the garage floor?

Thanks I will be getting to this Monday. I must run wild in the streets with the SBP expansion chamber for another day, got to keep testing wind chill factor. I am supposed to work on a rear mount bike but I keep getting sidetracked.
 
This sounds like fun. A few questions.

Do you mean the cover over the centrifugal clutch? If so, they do provide a tool for removing the clutch. Getting the rest of the manual clutch cover off is a little bit more complicated.

Would this explain why it will work after I stop and rest a second a couple of times? When I do this are ball bearing going to run wild on the garage floor?

Thanks I will be getting to this Monday. I must run wild in the streets with the SBP expansion chamber for another day, got to keep testing wind chill factor. I am supposed to work on a rear mount bike but I keep getting sidetracked.

Lordo

1. Yes, Thats the cover
2. No, I don't have a tool but mine came off easy with a little Lft. to Rt. wiggle.
3. The rest of the cover is easy but there is 2 screws under the C/clutch bell and 3 on the outside.
4. That is my guess that the spring is moveing.
5. No ball Brgs. 5 roller Brgs. Super simple crude setup. You'll see when you get in there. The spring
is supposed to hold the Brg. race to the right so it will only freewheel one way allowing you to peddle start the motor BUT you can NOT peddle the bike without turning over the motor unless you pull in the manual clutch. What I am doing to mine is takeing out the spring and rotating the Brg. race to the Lft. and putting a tack weld there to hold it in place. By doing this it will free wheel both ways. This way I can ride the bike without the motor like a normal bike but the only way to start the motor is with the pull start. That is because I am not going to have a clutch lever at all. The Manual clutch will never be disengaged, and virtually last the life of the motor....POPS
 
Thanks POPS will see if I can figure it out. I finally decided, that the SBP blue bike will be called "Blue Chaos". The wind in my face today was awesome even though I did not go very far, I did go quickly.

lord knows (LOL) you have given me enough info to see it it is the spring. I like the pedal option, especially since I can't pull start mine so I sure hope it is the spring. I will make sure I have my camera around and take pics as I tear into it.
 
Lordo

Your welcome
I had another thought. Oh NOOOOO
To know for sure, Take the small cover off-4 screws from C/clutch and go for a spin.
When the problem happens ( With the motor off), see if you can rotate the clutch bell to the
left. If it will rotate to the left( Even a little bit before it locks up thats the problem!!!). You don't have to worry about a puller because if you wiggle the clutch bell and the center that the clutch race and Brgs. ride on does not come off with it,thats OK. The bell and everything else will. Do not loose the 5 roller Brgs. If the Brg.center sticks to the crank, the way to reinstall is to:

1.Turn the bike on it's side(C/clutch side up).
2.Slide the clutch bell back on to the center that stuck on the crank after you have cleaned all the grease with brake clean.
3.If you look close when your cleaning the bell where the Brgs. sit you will see 5 rough cuts.
Slide the roller Brgs. into the rough cuts in the clutch bell dry so you can see what you are doing.
4.Dry fit the Brg. race and remove,Regrease and install.

Thats it. Thats all I know. Let me know how it goes. If you have to adjust your manual clutch there is a thread or a stickie or someone more knowledgable will kick in I'm shure...Good luck...POPS
I'll still be here to TRY to help.
 
Lordo

Your welcome
I had another thought. Oh NOOOOO
To know for sure, Take the small cover off-4 screws from C/clutch and go for a spin.
When the problem happens ( With the motor off), see if you can rotate the clutch bell to the
left. If it will rotate to the left( Even a little bit before it locks up thats the problem!!!). You don't have to worry about a puller because if you wiggle the clutch bell and the center that the clutch race and Brgs. ride on does not come off with it,thats OK. The bell and everything else will. Do not loose the 5 roller Brgs. If the Brg.center sticks to the crank, the way to reinstall is to:

Don't think that this will work, at least for me. There is no way of knowing if the next attempt will work or not. After the C.Clutch disengages slowing down resets the system. The next pedal attempt may work just fine. If it were happening all the time then it would be simple. Maybe I am thinking this wrong.
 
I am not quite sure what is up. Should the spring lie in the channel with a hook in the spring or connect to something? I don't see anything for it to attach to.
 

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The spring is supposed to go in 1 of the 6 large holes in the clutch
bell. The 1 that will line up and pull the Brg. race to the right to preload
the race. Was yours hooked up when you took it apart ? If not that was your problem.
Look close at the holes. 1 should show some wear as to where the spring should go.
POPS
 
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