Jahred
CB750 Member
Working on non-running 82 CB750SC/Nighthawk.
Replaced Coils and now firing on 4 instead of 1 cylinder. Still kills with throttle. Guessing Pilots.
In meantime I wanted to check valve lash as I see many suggesting this is critical.
spec is .08mm +.05 so 8 to 13, both intake and exhaust. All my valves are wider than .08.
I'm averaging .1775 I intake with gap ranging from .14 to .23.
On exhaust side, 4 within spec; averaging 13.625 and ranging .1 to .18.
I thought these could be adjusted like my Cobra with Lock Nuts. Huh. I'm reticent with my modest skills to actually pull the camshafts and do this shim thing.
Seems to me looking at feeler gauges that even .13 vs the .23 does not change the duration for jack and not likely my problem if engine won't accept any throttle. Idles fine. Higher RPM with choke.
Are these Valve Lash differences worth worrying about?
What's a reasonable price if I haul it to a mechanic for tune-up/carb cleaning?
Thanks in advance.
Replaced Coils and now firing on 4 instead of 1 cylinder. Still kills with throttle. Guessing Pilots.
In meantime I wanted to check valve lash as I see many suggesting this is critical.
spec is .08mm +.05 so 8 to 13, both intake and exhaust. All my valves are wider than .08.
I'm averaging .1775 I intake with gap ranging from .14 to .23.
On exhaust side, 4 within spec; averaging 13.625 and ranging .1 to .18.
I thought these could be adjusted like my Cobra with Lock Nuts. Huh. I'm reticent with my modest skills to actually pull the camshafts and do this shim thing.
Seems to me looking at feeler gauges that even .13 vs the .23 does not change the duration for jack and not likely my problem if engine won't accept any throttle. Idles fine. Higher RPM with choke.
Are these Valve Lash differences worth worrying about?
What's a reasonable price if I haul it to a mechanic for tune-up/carb cleaning?
Thanks in advance.