Author Topic: Replace CB750 cam chain while top end removed?  (Read 1586 times)

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Offline Catfish

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Replace CB750 cam chain while top end removed?
« on: August 20, 2016, 10:57:31 PM »
Hi all, im rebuilding the top end of my k7 and as part of that im replacing the cam chain. Have bought one of the chains with the link so i can put it on without splitting the cases. Currently the head and cylinder are off and the cam chain is under tension to hold it in place. Old pistons are still in place but i'm about to remove them to fit new oversize ones.

It strikes me that this would be the easiest point at which to replace the chain as it is vey accessible and easy to hold. I just join the new and old chains and turn the crankshaft around until tne new chain is fully on - yes?

So my question is: is there any reason i shouldnt do this or any reason why it wont work? Any advice appreciated.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Replace CB750 cam chain while top end removed?
« Reply #1 on: August 21, 2016, 09:54:30 AM »
New chains are always good just do a good job with the master link.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline Tugboat

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Re: Replace CB750 cam chain while top end removed?
« Reply #2 on: August 22, 2016, 09:48:37 AM »
Are cam chains available for CB750s with master links?
If it's worth doing, it's worth doing twice.

Offline flybox1

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Re: Replace CB750 cam chain while top end removed?
« Reply #3 on: August 22, 2016, 10:09:10 AM »
Are cam chains available for CB750s with master links?
Yes.  DID makes them.
I have a 100% un-used DID cam chain, still in the wrapper and box.  Lost the masterlink and went with a Tsubaki endless chain.
Its yours for shipping if you can locate a masterlink for it.
Just PM me. . .
« Last Edit: August 23, 2016, 11:51:00 AM by flybox1 »
'78 750K (F3 engine) PD42b's, Modified airbox w/K&N  filter, 40/110 jets, 1 needle shim, IMS@ 1 turn out. Kerker + Cone 18" QuietCore

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Offline PeWe

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Re: Replace CB750 cam chain while top end removed?
« Reply #4 on: August 23, 2016, 02:04:38 AM »
If cam chain need to be replaced, why not replace the primary chains with tensioner at the same time? They must be stretched and rattle as a crazy rattle snake .
A must is at least to measure the slack of the primary chains from beneath, oil pan removed... New chains have 65 mm, service limit 70 mm if I remember correctly. My last OEM chains had 67.5 mm after appr 30.000 kms, 75% touring, I replaced them. All with around 80RWHP

Engine is pulled out of the frame, not that more to do it all opening the cases. Then use a HD cam chain without master link. The cases might leak a little oil... new and better sealer + oil seals. check of bearings etc etc.
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