GS 1000 upgrade to GS 1100 G cylinder block /head

[BadBillyB]

That's very kind of you Billy!
In fact I believe the GS 1100 G base gaskets are thicker than the GS 1000's.
I still have some GS 1000 gaskets and they measure .6mm.
I decided to shave the cylinder block in any case as I prefer to use the thicker base gasket to keep the oil inside the engine and to get my CR as high as possible...

OK John, sounds like a good plan. It's very simple to make a deck checker like the one I posted and it's very accurate. I usually was looking for .038" to .040" piston to head clearance .......Billy

[BadBillyB]

Billy, not to jump the thread but I have a couple sets of 74mm pistons for two valve motors I bought from MTC. Got a set of Turbo pistons for my 78 1000 and a set of big dome pistons for my sons old race bike. I use the 1100G/GK cylinders, the sleeves are thicker than the 1000 sleeves and can go 74mm without a problem. Check with Cliff at MTC, they may still have some available.

I don't think we got too far off topic. The MTC pistons (in their 1982?) catalog shows turbo pistons with 7.8:1 CR.....Too low.....And the high domes with 13.5:1 CR....Too high for street application. I ran a MTC 1175cc piston kit in my street bike (back in the 80's) , and it was rated at 10.5:1 but it was IMHO totally underrated. Looks more like 11.5:1 using the eyeball. I ran a mix of Avgas and premium in it but couldn't really go too far from home on a tank. They were also very heavy compared to Wiseco's....Heres a pic of MTC 10.5:1(on left) and Wiseco 13.5:1(on right) If you look at the top ring placement you can see where I machined the Wiseco piston to push it even deeper into the combustion chamber........Billy
Picture 162.jpg

[John Kat]

I finally got my cylinder block back from the machinist...
It's now back on the engine and it looks OK to me with respect to the deck height?
In retrospect, I believe it's not a good idea to use a GS 1100 block ( unless you want to go beyond a 73 mm bore) as you must shave it to get the correct deck height.
I took .9mm off but 1 mm would have been OK.
Here's what it looks like: