Jug has to be spaced up to match. The larger bore and larger stroke will increase crankcase compression. Going to slip fit the crank and clutch so I can easily brake it down if I want to stuff the case later.
It's a 44mm stroke I checkedGuys at MZ are pretty sharp. Good people to deal with. Having a lined bore will be a great thing!
Is this 4mm on a 38 or 40mm crank? Other words what is the total stroke?
The Stihl conversion I'm attempting (same as Zeda MS) is designed for a 40mm stroke. The unknown at this point is the piston pin height. Still waiting on the parts. What you are doing is similar enough to be of help to me on my project. Will follow closely.
Interestingly you can button the ends of the piston pin to also raise primary compression.
You asked me if the +4mm stroke was from a 38mm crank or a 40mm crank I was just answering your questionI was going to use a 40mm bottom end. The Stihl saw that the cylinder/piston come from uses a 40mm stroke. That keeps the port timing correct. We may be taking about two different things.