Author Topic: cb650 cylinder head removal and rocker repair  (Read 1961 times)

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Offline IainC

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cb650 cylinder head removal and rocker repair
« on: August 24, 2008, 10:27:59 AM »
I was in the process of adjusting the valves on my cb650 when one of the adjusting bolts sheared off. I'm thinking this is due to me over tightening the nut, and the previous owner having over tightened it as well as it was an absolute pain to remove. Now learning from my mistake and having to order the replacement bolt, I'm in the process of removing the cylinder head and getting this all straigtened out.

I'm at the point right now where are the bolts were loosened as per the instructions in my clymers manual, then removed, and the head is waiting to be pulled off.

Before I go ahead and do this I'm waiting for my buddy to drop by with the replacement part, I figured I'd ask you guys for some advice when it does come to pulling it off. It appears to be stuck on there fairly solid with just the gasket, the front lifted up slightly but the rear is firmly in place. Any recomendations when it comes to pulling it off, or should i just gently pry it apart? And secondly, any other words of advice before I go ahead with this repair? I've noticed a few other threads which people have recomended using rubber bands to avoid having the valves bent, so I'll try that, but should I have those on during removal as well?

Offline kslrr

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Re: cb650 cylinder head removal and rocker repair
« Reply #1 on: August 24, 2008, 10:59:06 AM »
I don't recall mine being difficult.  Are you sure you got all the botls?  You don't need the rubber bands during removal.  I had never head of using rubber bands but what you are doing is holding the rockers up and clear of the valve stems so that they do not hang up on the edge and push on the side of the valve stem, bending it.
Now  1972 CB350FX (experimental v2.0)
        1981 CB650c Custom with '79 engine (wifes)
        1981 CB650 engine
        2004 HD XL883C Custom
        1977 Yamaha XS750D (in progress)
Then 1972 CL175
        1964 Yamaha YGS-1T
No ride is a Bad ride

Offline IainC

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Re: cb650 cylinder head removal and rocker repair
« Reply #2 on: August 24, 2008, 11:06:54 AM »
I've removed all the bolts on the top, and can't find any that I'm missing. Are there any on the sides that are hard to find? I've got a 79 engine as well.

Offline Buber

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Re: cb650 cylinder head removal and rocker repair
« Reply #3 on: August 24, 2008, 11:19:18 AM »
Hmmm,if you are fixing the rockers/valve adjusters, you actually don't need to take the cover off. Unless you want to, for other reasons....
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Offline kslrr

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Re: cb650 cylinder head removal and rocker repair
« Reply #4 on: August 24, 2008, 11:25:01 AM »
How many bolts did you remove.  There should be at least 18 22 (just looked at the manual).  There are 4 under the center tappet cover.  Also, there is an O-ring instead of a gasket and maybe someone previous used RTV to seal it, which would kinda glue it in place.  I know I did.

Buber makes a point.  However, if the broken piece is down in there, it is a good idea to retreave it.
« Last Edit: August 24, 2008, 12:06:32 PM by kslrr »
Now  1972 CB350FX (experimental v2.0)
        1981 CB650c Custom with '79 engine (wifes)
        1981 CB650 engine
        2004 HD XL883C Custom
        1977 Yamaha XS750D (in progress)
Then 1972 CL175
        1964 Yamaha YGS-1T
No ride is a Bad ride

Offline speedy gonzalais

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Re: cb650 cylinder head removal and rocker repair
« Reply #5 on: August 25, 2008, 12:05:39 PM »
why are you removing the head ? why not just remove the cam?
82' C90
87' yamaha T80
79' CB125T/CD200 project
82' CB650z
80s kawasaki ae50/150cc project
92' Suzuki GSXR600
80' CB250N