Motorcycle Repair: ported head, honda z50, head surface

Question
I am boring out a honda z50 cylinder jug to .50 over and I want to port out the head, what measurement should it be milled to? Also will I need to replace the manifold and carb? Thanks in advance, Jeff  

Answer
Hi Jeff,

The piston to wall clearances should be about 0.001" to 0.002" after honing, generally. I don't have the specs for that MC.

Measure piston deck height and mill head surface according to your calculations. You'll have to work the formulaes from your measurements. If you are not experienced in this type of work, have it a pro do it for you. Mistakes lead to detuned performance and/or engine failure.

Check into a book titled: Two Stroke Tuners Handbook

A very good resource for tuners. All necessary scientific intel in there.

Respectfully,
Mark Shively