Is it essential to have a totally dry base gasket when installing new ones? There is so much oil in the process of oiling the cylinders, pistons & rings while putting everything back together. So easy to get oil on the new base gasket in the process.

 

Don't use so much oil. When you put the cylinder on The top ring pushes most of it out anyway.
Clean & dry for the gaskets to seal. I also true up the cylinder gasket surface on the lathe. Evo cylinders are almost never flat.

 

Evo cylinder bases are not machined from HD.
The spigot OD is turned, but the machining process ends there, and upon close inspection, you can see where the tool ends.
Trueing up a set this morning, as a matter of fact.
Scott

 

I did have a local Harley machine shop turn off the 25 year old gaskets....So got the cylinders trued up in the process (2 for 1)

 

We clean/prep surfaces prior, touch, "0" the indicator, skim, and dial .002" at a time until gasket surface is fully machined.
Did 2 sets of those today, total.
Our Facebook has evidence of the process.
Scott