Centrifugal Help ? Before I take centrifugal clutch apart.

wan37

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I have a 48cc engine with a centrifugal clutch and today as I got in the driveway it went bad no pull from motor at all, still running Idles great.So I shut it down.I went to roll it in garage and it rolls with a little drag but not much with clutch lever out,or in.So were should I tear a part first.I want to see who can get my problem answer first.I'm kinda bummed,but lets have some fun guessing the problem. Thanks A bunch!
 
I have a 48cc engine with a centrifugal clutch and today as I got in the driveway it went bad no pull from motor at all, still running Idles great.So I shut it down.I went to roll it in garage and it rolls with a little drag but not much with clutch lever out,or in.So were should I tear a part first.I want to see who can get my problem answer first.I'm kinda bummed,but lets have some fun guessing the problem. Thanks A bunch!

First if the bike rolls with the clutch in or out, what I would check first, start with the cables, may have too much slack, then check the bucking bar and bearing, after all that then I'd adjust the clutch. Also check to make sure that you put the woodruff keys back in.
 
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Thanks Al
I thinking you are right about the wood ruff keys,because the centrifugal clutch does not come with notch for the key I made one it was to big so I just install it with out the key.I read in one of the forms that you may go without the key.I'm hoping that's the problem but don't know.I still don't know for sure tho.I really thought the clutch lever would work tho.So any other know any thing about this problem?I will start to tear a part tomorrow morning so give me some in put please.
 
On these kits, I have no working knowledge of either the centrifugal clutch or the pull start, but I'm sure that they are as easy to work on as the rest of the bike.
 
you have just turned me off the centrifugal clutches on HT's fulltime :)

you mean by "notch" that it had no keyway in its bore?

correct terminology makes deciphering issues so much easier :)

if it has no keyway.... *shudders*

what are you meant to do, glue it on? omg...

people can cut them for you but on that size bore and that width...pay up buddy!

no keyway.. sorry. im on lunch! :giggle:
 
Working with centrifugal clutches in the past (not on a HT), they are a few ways that the clutch is held on to the shaft. Threaded on, like a automobile (not on a HT), and with a key and bolt. Other then that, I can't see how the crankshaft will turn the clutch very long before it spins on the shaft. Something has to hold the clutch on the shaft as the bolt in the end of the crankshaft won't work long or at all.

I really can't see how this clutch will hold, if it in fact has no keyway, There might be, but I can't see one. How about a picture that we can see into the small gear.
 

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I don't have a picture of it,but I know it really needs a wood ruff key.The gear that replaces the small bevel comes without a slot for the key.So I read on one of these forums when installed either make a slot for the key or put it on without the key.I got about 2 hundred miles on it with out it.I also know when you buy a engine with the centrifugal clutch all ready installed the key it not there too.The gear is kinda tapered so it fits on snug when press on.So vibration loses it up I think.I'm getting ready to tear in a part and check.Thanks AL and everybody else.
 
The right way, and The Chinese way!!! I think I put a tack wield on it (as a machine shop charge would be high for these cheap engines), before I trusted it for any amount of tine. One that could be easily ground off.

Holding a small gear in my hand, thinking about installing the stock gear in place of the non keyed clutch gear.
 
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so wait...if you run a centrifugal clutch on a h.t. engine, you still have a manual clutch lever?
Without a woodruff key, how is the clutch drum supposed to couple wiht the shaft? seems to me that the shaft would just spin inside the clutch and the clutch would never work.
that doesn't sound right to me.
 
Well the bolt that come with clutch kits from bgf is to long.The centrifugal the gear slip out a bit and it was just turning and now I think the I fixed it with a shorter bolt.The shorter bolt is hard to find but tractor supply has one.So if any one needs to know I will tell them what size to get.Plus I also added the slot and key.
 
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