Topic: CB750K Clutch replacement

[Dolomite]

I've tried to search this many times on the forum but haven't really found anything too helpful. I have a 76 motor with the 76 basket, but a lot of parts from a 78 motor. I got my new friction plates from cyclex and am doing the clutch afterwork. I have the double steel plate from the 78 that reduces the chatter, can this be used in the 76 basket? The 78 basket is not useable. With the double steel plate and frictions the clutch pack comes out to just about 1.56 and I know for a pre77 clutch it should be 1.46. Is that because the pre77 baskets didn't have the double plate? Will there be any issues using the 1.56 pack in the 76 basket? It fits, snug, but I'm not 100% on how much play should be in the pack once assembled. Any tips would be great, thanks!

[bryanj]

There is a bulletin on here somewhere about fitting that double gold wing plate and what to do. You need to search that out

[Dolomite]

I appreciate the quick reply but as I stated the search function hasn't been very helpful in narrowing down what I am looking for. If you have a better suggestion other than "you need to search it" then I would be glad to try it. Thanks.

[RAFster122s]

Use Google with site:http://forums.sohc4.net in your search string

[madmtnmotors]

There are differences in the early clutch cover (the aluminum case cover, not the tin cover) vs the later case cover but I'm not sure when the change was made. The later clutch is taller as you discovered by measuring (kudos!) and there are earlier clutch covers that extend about 1/4 further into the case. This is mostly at the back of the lower screw boss down by the kickstart shaft where the outer tin cover attaches to this case cover. The inner portion of the screw boss inside the case cover can be cut/ground away to avoid clearance issues between the earlier covers and the later (taller) clutch stack. I'm not sure if there are any issues with the taller stack inside a shorter basket. As bryanj indicated, there is a service bulletin covering the procedure for upgrading the early clutch to the later clutch.

[Dolomite]

This is the best I could do as far as finding the bulletin. It looks like once the double plate is inserted the innermost friction plate is also removed and leaves a metal plate contacting the basket. Does that sound right?

[PeWe]

Use the K6 clutch as it is without the double plate.
Or install a complete later clutch from an F2 or later K, outer cover included.
I used CycleX clutch plates and they sticked together very quick. Need of rock bike forward- backward to get them free after a night park only.
Replaced by EBC plates helped.
Cruzinimage cheap clutch plates work fine too.

[Dolomite]

Use the K6 clutch as it is without the double plate.
Or install a complete later clutch from an F2 or later K, outer cover included.
I used CycleX clutch plates and they sticked together very quick. Need of rock bike forward- backward to get them free after a night park only.
Replaced by EBC plates helped.
Cruzinimage cheap clutch plates work fine too.

I managed to "persuade" the 78 basket to separate from the primary gears. How tight should the larger outer friction plate fit into the basket? It does not freely want to drop in and would also need some....."persuasion"

[bryanj]

I cant help it if the search function cant find something i know is there as i supplied it, and any answer when i am at work has to be better than ignoring the question.

[RAFster122s]

Search with google using site:http://forums.sohc4.net in your search string and it will give your results from the forums site...

[PeWe]

Use the K6 clutch as it is without the double plate.
Or install a complete later clutch from an F2 or later K, outer cover included.
I used CycleX clutch plates and they sticked together very quick. Need of rock bike forward- backward to get them free after a night park only.
Replaced by EBC plates helped.
Cruzinimage cheap clutch plates work fine too.

I managed to "persuade" the 78 basket to separate from the primary gears. How tight should the larger outer friction plate fit into the basket? It does not freely want to drop in and would also need some....."persuasion"

It usually drop in after some fiddling, centering it. Sometimes a plate inside the outer that does not sit as deep in as it should.

[Dolomite]

I ended you up installing everything in the K6 basket using the field  repair assembly. Clutch is working great now.