CB750 Engine troubles

[pop_vamp13]

First bike build.

Picked up a cb750 at a local salvage yard, a little rough, but ran.

Changed the oil, plugs, etc. Cruised around a little, no more than probably 50-60 miles, started getting some oil coming out of the exhaust, with reduced power to the point where it wouldnt even pull up my slightly sloped driveway.

I tore the motor down. Replaced rings, honed the cylinders, new gasket kit, rebuilt all the carbs.

Got it all back together, timed the valves with the crank just as it showed in repair manual.

But... just as it usually goes something isnt right.

The bike will not start. It is as if the timing of 180 out. The #1 and #4 carb push air and fuel out, as if the valve timing is extremely off, or the valves are sticking.

As I am new to this, I am going to assume that if several of the rocker arms are super out of adjustment, say over 1/8 gap, that those particular valves are stuck open? Half of the feel gauges put together could probably fit in the gap.

Should I have ground down or replaced the valves when I did the rebuild instead of just the rings, and new gaskets? I simply just took the head off, and then bolted it back on, didnt adjust or change anything.

If you need anymore info to help me with this problem, let me know.

Thanks!

 

[pop_vamp13]

Thanks, ill check out the coil trigger wires, and the points.

A few of the valves have such a large gap, that even if you screwed the tappet all the way in, it would still have gap much larger that what the manual has them being adjusted to.

Do you think that these particular valves are stuck open?

 

[pop_vamp13]

Tell you what......

I'm still in college... You make a trip to fix these valves.... I'll set up the college aged lady semi-amateur chopstick gynocology. ;D

 

[surffly]

Did you do any checks to the engine before you tore it down?
A leak down test would be able to tell you if the head needs to be rebuilt.
My guess is a junk yard bike that was sitting and was worn out enough to need rings has a bad head as well.
Did it need rings?
was everything mic'ed up to know what was good and bad?