Rebuilding Auto Clutch

[DeRider]

All righty, kick starting on my 74 k3 is not well, very little resistance when kicking over, have to be gentle for the kick start to engage. decided to replace the springs in the clutch, ordered the stock, not the heavy duty from chp. Took clutch cover off and removed clutch from shaft. went by the directions in clymer and also watched a video of some hooded sweatshirt dude. tore down the original clutch and replaced the 4 clutch springs, did NOT replace the friction discs. Put clutch back together installed on bike and now have no resistance/not turning over motor at all.
took back apart, removed clutch tore down and looked at it and put back together again following the pic in clymer on pg 124.. did notice when back together that I am able to freely spin the clutch center and drive gear outer by hand with no resistance. Should these turn freely in hand when all back together? I am thinking maybe the friction discs themselves are shot/extremely worn? I don't own a micrometer so can't check and just ordered new discs today from honda.
Should the friction discs (a) have material on only 1 side and smooth metal on the other, friction disc (b) has material on both sides.the pic in clymer only shows a fabric like sidefacing up in the basket.
Sorry if this sounds like a stupid question but I'm at a loss right now, have tore the clutch apart a few times now and everything I have installed is exactly what it shows in the clymer.
Putting the locking circlip over the clutch plate (b) to lock the clutch together takes little to no pressure at all to slide into its groove thats why I'm thinking friction plates worn.
Again sorry and apologize for being long winded.
Rich

 

[69ST]

No worries about the length of your post. This is one of those issues that takes several sentences to describe well, in the first place. For now, let's start with something easy, the plates & discs. The steel plates should have a clean, dimpled, surface on both faces. If the dimples are worn smooth or there's heavy scoring, heat discoloration, they're probably worn out...and the friction discs with them. If they're in good shape, you may just need new friction discs. How thick is the friction material?

Make no mistake, you may have something incorrectly indexed in the clutch pack. But, the original problem was slippage while trying to kick the engine...while everything was ostensibly untouched and thus correctly assembled, from the factory. Sounds like wear, imo. I assemble these clutches with finger pressure, the springs don't do nearly as much as with a full manual; most of the clamping pressure comes from centrifugal loading as engine rpm comes up to normal operating range. And, your engine is likely down on compression, which would put less load on the clutch while kick starting.

 

[DeRider]

Hey Racer, thanks for the reply, my engine is weak on compression but runs real good, maybe I'll freshen it up this winter with new rings and I've learned with another ct and z50 that tearing down the head,replacing the valve springs and just lapping valves makes a BIG difference.
Back to orig. question, should the clutch center and drive gear outer be able to be turned by hand in the clutch basket when it is all put back together and I mean put back together as having the clutch in my hand not installed in the bike. thinking again it's leading me down the path that the friction discs are shot.
Is anyone familiar or purchased the complete "NEW" auto clutch kit from hondabikerescue on ebay?
Thanks Rich

 

[69ST]

Something's not right. Think about how the clutch works. It's normally engaged, until either the mechanical linkage moves the pressure plate, decoupling the plates & discs, or the centrifugal weights are moving slowly enough to release most of the clamping force of the disc/plate assembly. There has to be some residual friction, even at zero rpm, otherwise you couldn't start the engine. If you can spin the clutch easily by hand, there's no way it's going to have enough grip to spin the crank via kickstarting.

Starting is where clutch slippage is most likely to manifest as the clutch wears out. That's a good thing, really, kind of an early warning. Based on what you wrote in your initial post, I suspect that you have worn friction discs, plates or both. And, something is incorrectly assembled. This might be confusing to you at the moment, there is a learning curve. That said, the fix should prove quite simple...ultimately.

I wouldn't be looking to replace the entire clutch assembly. OEM service parts are readily available & dirt cheap. New springs, plates, friction discs, throwout bearing & gaskets together should dent your wallet by more than about 50 bucks. I cannot recall the last time I saw a worn out CT70 clutch basket. For a stock, or modestly tuned 88cc build, a healthy stock clutch is fine. If you're itchy for an aftermarket clutch, source an HD billet assembly from hondatrailbikes. That's reliable with (relatively speaking) big hp & rpm beyond 11K...massive overkill on a stocker.

Check out the pix. Don't know if they'll be all that helpful as they don't show every detail, such as how the splines should be oriented. Hopefully, they won't confuse you even further.:4:

 

[DeRider]

thanks for the pics, I will find out when the new friction discs arrive.... Rich