Head job

[b1kawa]

Howdy all, now that I got your attention, after having no
compression in 2 & 3 cyclinders, (1981 GPz1100B1 Fuel injection) I
took the head off and discovered the 2 & 3 ex valves were slightly
open, one valve is slightly bent and were it slides up and down in
the head there is a shaft and that shaft is half broken away. Now
would anyone know could this have caused the valave to bend or if
the valve had bent some other way could the valve have caused the
shaft to brake away?........Next, since I have another complete bike
for spares if I use the head of it do I use the cams/shims etc also
or do I just use the head and use cams etc from my original one
(does that make sense)??????
Anyway since the head is of it will be getting a head job (hence the
heading) by way of porting and polishing........

Phil Livo

[Anonymous]

There are a number of things that could cause bent valves...Cams can become worn, you could have somewhere had fluid such as fuel oil or water in the cylinder...it could have been stuck when it finally turned over...I'd use the other engine and have this one completely checked out. I suppose that even misadjusting the valves then really romping on hte engine could do it. being cold and starting it and taking off before it was properly warmed up, over reving...thereare so many things. Timing comes to mind, but it wouldn't have to be a timing issue. sometimes temperatures cause it, or even pressures cause it. Either way I think ALL of us on the Forum (at least I know I'm VERY interested) are curious as to what you find.

[b1kawa]

So far, one bent valve, one cracked valve stem guide, proberbly the bent valve cracked the valve stem guide.
The head gasket off the spare bike was leaking so I will get the head checked out and fit that after some heli coils have been done on the cam holder holes.