Head on Valve Spring Compressor 1/4

That's very interesting Jim. I will have to check the pistons for comparison - mine are 1982 and the others I'm not sure, but most likely 1980 - 81.

A very related to all this a couple questions. In my project, all will be new: new rings, deglazed cylinders, new valves and machined seats, new seals.
I will definitely need breaking in time for the machine! What is recommended by experienced users? On one hand, I know you shouldn't push the engine beyond certain RPM until a certain mileage is met. Then it's recommended to operate the engine at a variety of speeds, not a constantly similar rpm's. What worked for you did you find in practice with these bikes?

The second question is, which engine oil to use? People are raving about Rotella T 14W-50 diesel. I am using it now in Vmax and Goldwing. All works great, but I think the clutch worked somewhat better using the native Yamalube 20W-50. Vmax doesn't like synthetic oils because of clutch slippage.

OH NO - Not the "Oil" thing again ?:S
...and so no one is offended -

LOL This is the FIRST time for me to talk KZ13 oil! :dry:
Isee.... One more reason to make it quick, short. and sweet
So.. what oil do you run scotch?

Considering the "Shell Rotella" now I have new valve-stem seals and can keep oil IN.

They sell it in a big bucket. Becomes quite reasonable when you buy it. I couldn't find any in depth discussion on oils on the forum using the search box... maybe I should stick to the Rotella?... hmmm