GS1100 Head interchangeability

[dgeorge]

I posted this over in the tech section, but thought I would try here also. I have a 1983 GS1100GK with the 2 valve head, and I think I may have bent some valves, due to it jumping time, (forgot to loosen the cam chain tensioner ). #4 cylinder has no compression at all, so if I have to tear this thing back apart for the fourth time, I would like to make it worth my while and upgrade to an Wisceo 1166 kit, but I believe they are only for the four valve heads. So would it be possible to replace my 2 valve head with a 4 valve head from an 1100e? Or what are any other options available to me? Thanks in advance for any help or advice on this. Also something else that just came to mind if I did this swap would I have to change my carbs, I have the stock CV carbs now. Any Ideas?

[humhead]

2 valve & 4 valve heads aren't interchangeable. The 4 valve piston kit won't work either. I think a 2 valve piston kit is the way to go. Your stock bore is 72mm, if memory serves. wiseco has a 73.5 mm overbore kit for the GS1000 That might work (pin to crown distance and pin diameter would need to be checked) As for carbs, Any set that fits an 80 or later 1000 should fit your bike. Be careful - hi perf carbs might not be right for a touring bike.

[cbxchris]

humhead hit it on the head!

[Anonymous]

I thought all post '80 engines were 4 valve. Is the '83 110 really a 2 valve? What other post '80 engines are 2 valve?

[humhead]

The chain drive models switched to 4 valve/cylinder engines starting in 81 the shaft drive models kept the 2 valve head because it was still great for cruiser/touring bikes. The 550 chain drive models changed to 4 valve heads later (83?) I'm not sure about the 2 cylinder models.

[dgeorge]

Thanks Humhead that is kind of what I thought, but wasn't sure. I emailed Pro-Flo and they said the Wiseco 1133 kit would work as long as I have 18mm wrist pins, so anyone know if that is what is in the 2 valve 1100's?