Series - Measure Bore

[adesteiguer]

I need to check the cylinder bore diameter on my Series III 2.25L petrol. What's the best tool to do that? May need to have it bored out and oversize pistons installed, but first want to see what the diameter is now. Stock is 3.625 in. according to the manual.

[gudjeon]

I use a good old fashioned telescoping gauge. Expand, tilt in the bore. Loosely tighten up the knurled knob. Tilt it past level and tighten up to read with vern or micrometer. Doing this centres it automatically so your reading will be consistent.