Home Forums Tech Talk Piston to Cylinder Clearance Reply To: Piston to Cylinder Clearance


Yes, a bore gauge is optimal for measuring the ID of my cylinder, however at the moment I don’t have one..  For now I’m ok using my telescoping gauge and mic to get an idea.  All of the measurements I took were all within .0005″ of each other.  Close enough to get an idea of what I’m starting with.

Also yes, I know the cylinder will need a hone, and the size will change, but my goal with this measurement was to get an idea of what the original piston clearance was, so when the cylinder is cracked checked, honed, and measured, I’ll know what piston size I need.  Once I saw there was a .010″ gap, that threw up a red flag and my reason for posting.  And it’s nice to know that what I found about proper piston gap is correct.  Just seems odd that this supposedly being a DDR engine that hadn’t been raced sense the last rebuild that they would have used a piston that small.

Thanks for all your replies thus far!

2008 GP 8 Honda 125 / TM K9B
Building F125 Enduro