Author Topic: 77 cb750 clutch  (Read 564 times)

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Offline yellowjacket

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77 cb750 clutch
« on: February 20, 2021, 03:49:18 PM »
I finally got the bike up and running. Sounds great starts right up(haven't ran it for 3 years). While up on the stand I went to shift it and it went right into first and ran fine.  Tried to engage the clutch and the clutch did not take it out of gear.  I tried to adjust the clutch as the manual says and still nothing.  Any suggestions before I start in on a new clutch.  Thanks.

Offline CaptFatCat

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Re: 77 cb750 clutch
« Reply #1 on: February 20, 2021, 04:38:10 PM »
I had this problem too, clutch plates stuck. First warm up the engine. Sit on bike while in gear (not running) and engage the clutch lever then rock back and fourth and see if it will free it.
My dad years ago told me to hold the clutch lever in with a wire wrapped around it and walk away, come back in a day an try the rocking again.
Some may say this weakens the clutch springs???? I always thought week clutch springs are better than no clutch at all.
This has worked for me many times.
Resurrecting a Herman Munster CB750 from a few old baskets of K2 and K7 parts.

Offline yellowjacket

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Re: 77 cb750 clutch
« Reply #2 on: February 20, 2021, 05:46:29 PM »
Thanks, I will give that try.

Offline ekpent

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Re: 77 cb750 clutch
« Reply #3 on: February 21, 2021, 06:35:36 AM »
 I've had a lot of stuck clutches on 750's that I have worked on that have been sitting for some time. As mentioned tying the clutch lever to the handle helps but the most important thing is to get some fresh warm oil running through the engine for awhile. Also as mentioned once warmed up well if still stuck rocking at back and forth in a higher gear with the engine off should work. I wouldn't jump right in tearing everything apart unless the engine was a swamp rat.

Offline BenelliSEI

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Re: 77 cb750 clutch
« Reply #4 on: February 21, 2021, 09:01:07 AM »
This happen to me occasionally. Usually first ride of the season.....

 I just roll down an incline and snick it into gear, up and down the road a few times, shifting and pulling/ releasing the clutch and they usually come free pretty quickly.

Offline PeWe

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Re: 77 cb750 clutch
« Reply #5 on: February 21, 2021, 10:49:02 AM »
Rock the bike forward-backward with clutch lever fully in is standard procedure on my bikes.

It will clonk very hard when gearing to 1st gear when engine is started on a sticky clutch if not push clutch free before.

I had a set of fiberplates that were really sticky. I had to replace them despite new.

Nowadays enough to push bike forward a little to release before start.  If in a hurry I start on 1st gear then no problem.
Slow smooth riding until engine is warm.
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline yellowjacket

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Re: 77 cb750 clutch
« Reply #6 on: February 21, 2021, 12:42:22 PM »
Thanks for the advice.  Let it warm up for a good 15 minutes and the clutch now works. I can now ride it once all this snow is gone.

Offline BenelliSEI

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Re: 77 cb750 clutch
« Reply #7 on: February 21, 2021, 01:03:01 PM »
Excellent!