Centrifugal clutch kit

Mar 16, 2016
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america
I've seen videos of people installing centrifugal clutches on a stick 2 stroke. The only websites selling them all seem to be out of stock though. Is there anywhere to buy these now and how well do they actually work? Thanks for any info.
 

ZipTie

Active Member
Jan 8, 2016
750
48
28
Mpls Mn
Chinese MFGs generally carry no inventory in order to keep their costs down. When a re-seller runs out its on a 60 days out for the companies to make them plus a months ship time so they run out they need 90 days to get them back in stock and generally don't order till they feel confident to buy 50-100 or more of any item they feel they can sell. Also most want to fill an entire shipping container also so they batch other stuff they are importing in order to save money on shipping.

here is one ebay seller that has them. I guess they work well from what I have heard with a wide pedal set? and a pull start.

http://www.ebay.com/itm/Complete-Ce...ash=item3f5d7a1cdc:g:~oYAAOSwG-1W1Ioy&vxp=mtr
 
Mar 16, 2016
118
0
16
america
After Agreen's comment i found that one too. From what i understand you don't need a pull start you can still pedal start. But I think thats only on some of them? I'm really not sure all i know is from the few youtube videos i could find of people actually installing them.
 

ZipTie

Active Member
Jan 8, 2016
750
48
28
Mpls Mn
After Agreen's comment i found that one too. From what i understand you don't need a pull start you can still pedal start. But I think thats only on some of them? I'm really not sure all i know is from the few youtube videos i could find of people actually installing them.
One would think the manufacturers and sellers would state the other needs or advantages etc. But nope they just show it...strange marketing at best.
I would think only the outside of the clutch housing would spin during pedaling, so bump starting the engine would be impossible. But this is confusing and I could be wrong, however I believe I am right that a pull start is also needed. Can anyone else weigh-in here???
 

ZipTie

Active Member
Jan 8, 2016
750
48
28
Mpls Mn
Ok that makes sense now. However... he has a jackshaft, does that affect rotation direction of the clutch housing during bump starting?
 
Mar 16, 2016
118
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16
america
No it's the same. Since it's all connected with chains rotation is always the same direction between cogs/gears. You pedal start a shift kit the same as one directly connected to the wheel except you have to turn the pedals since there's a freewheel between the tire and the engine.
 

ZipTie

Active Member
Jan 8, 2016
750
48
28
Mpls Mn
I guess I've never thought about it, thanks for the info and education to me and all that read it in the future. Suddenly Id like to try one out on a build. It was the lack of bump starting is what stopped me in the past to consider one.
Zip
 
Mar 16, 2016
118
0
16
america
Me too. The pull start is pretty universally hated because of the quality so i didn't consider it until i reently did some more research. I'm building a new bike with a shift kit designed for off road use and this clutch would be really helpful.
 

msrfan

Well-Known Member
Sep 17, 2010
1,800
96
48
Southern California
I just built a bike with a kit I've had for a few years and it had a centrifugal clutch and pull start. Mine came already installed in the motor and it does have a sprag bearing built into it. So you retain the manual clutch so you can lock it to push the bike around or pedal start. After replacing the junk pull rope with a quality one, it works great. I don't even pedal start anymore. Just have the manual clutch lever locked and pull start the motor, let it warm up and let the manual clutch out. It idles nicely until you gas it and take off using the auto clutch. I'm very satisfied with the way it works.





 

Agreen

Member
Feb 10, 2013
792
11
18
Southeastern GA
I have had a pull start longer than the centrifugal clutch and it's lasted. They did upgrade them at some point in time, so the hatred you're reading is towards the old style. The new style has a plastic bushing to prevent the cord from getting frayed and broken. It still works great after a year of use.

Now, there is a trick to the centrifugal clutch. You have to either buy 5 (yes, FIVE) clutch gaskets to space the cover out. Another option is to run without a cover, but that's asking for a chewed up leg or dirt/debris to enter the clutch. The best option is to cut your stock clutch cover up. I used a drill to make a hole in the middle of the cover. Then, I put a bolt and nut through the hole and tightened it up. I used the bolt to chuck the assembly in my drill press so it could spin free. I then used a cutoff tool to cut the side off the cover to effectively make a 1/4" spacer for the new cover. Note that I never said to turn the drill press on!! It's just to keep things lined up. Kind of like a backyard machine shop.

And yes, you can definitely bump start the engine with the centrifugal clutch kit. It does, in fact, have a one way clutch. You can also use it with a shifter kit.
 
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Mar 16, 2016
118
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16
america
Okay i see what you're saying with the gaskets. I don't have an angle grinder so ill probably just go with the gaskets. The issues people were having with the pull starts seemed to all be fixable with a better cord so i wasn't too worried either way. Good to know they've changed though. Thanks for the info.
 

Agreen

Member
Feb 10, 2013
792
11
18
Southeastern GA
In this video by another user, he explains the installation process. You can do the same lubrication port on mine too. And you don't need an angle grinder to do that, but it definitely helps.