Rocker touching valves after rebuild

[Johny Boy]

Hi everyone, well my engine rebuild is almost done cb550
However, when I try to refit the rocker cover assembly the rocker casting is touching the valve head before the cover casting bottoms on the head in 2 positions, this is with the adjustment screw fully wound out.
I had the head skimmed,valve seats machined and new valves fitted.

Has anyone come across this before?

Any advice would be very welcome

John

[Bryanj]

Nope but cutting the seats may have let the valves come too far up, try fitting the cover with no cam fitted and see what touches

[Oddjob]

There are always some valves that are down on tdc.

[McCabe-Thiele (Ted)]

There are always some valves that are down on tdc.

Good point Ken, I guess Johny could rotate the engine and see if the high point moves to different valves or simply fit the top cover, adjust the valve clearances with a somewhat wider gap (not running the engine) to put his mind at rest on the valve seat cutting. If all valves close okay, set the correct gap and re-check.

[Johny Boy]

Thanks for this, I did not know that some valves would be open at TDC. Key point.....
Checking against the Haynes manual, the valves which are contacting are #2 exhaust and #3 inlet
If I'm reading this correctly then I have #4 on tdc on compression.

Thank you all so much, this now makes sense
I will bolt her down in the morning and let you know how I get on

Ýou guys are awesome

[Johny Boy]

Thanks again all, all sorted now, although setting the valve clearance is a pain!
Right angled slip gauges would be handy!!

Ride safe

[Oddjob]

You can buy right angled feeler gauges as it happens.

[Bryanj]

Fleebay