Doing the cam swap now - Cam chain tensioner question please....

[Cemoto]

Hello All,

I'm doing the cam swap now.  900cc cams into a 1980 CB750F Super Sport.

The exhaust cam chain is still real tight making it difficult to reinstall the sprocket.  I had a helper pull up on the tensioner with pliers as shown in the factory manual, really didn't do much, maybe moved it 1/4" upward and provided a small amount of slack.

Thought I'd look at the parts fiche to get an idea of what is in there.

When I did I saw that the tensioner in the center has two rearward lock nuts.  The manual only shows loosening the lower nut, are you supposed to loosen the upper rearward facing one also?

Any tips would be greatly appreciated!

Thanks!

[OTTODOCTOR]

Loosen both and gently pull up on the shoe to gain enough slack . Tighten the bottom one just enough to hold it in the up position . This should get you enough slack to get it done . -- Worked for me . -- Otto -- There is a great amount of information for these bikes on the DOHC CUSTOM forum ( www.cb750c.com ) -- see you there ??

[Cemoto]

Got it - Thanks!  

Had to buy 15 shims!  

So far $100 for two used cams (W/ shipping) and $128 for shims.  

When I installed the "new" cams I had less than .0025 clearance in all but one valve and was only able to reuse one shim.

Waiting for the shims from BB to install.

Regards,

[punkindriver]

loosen both rear acorn nuts.take a big screw driver and push n on rear cam chain tensioner bow to provide
maximum slack then tighten nuts to keep slack.