Motorcycle Repair/honda cb77


i got a barnfind chopped honda 305 cl77 frame cb77 engine it has been taken apart the pistons are cb77 with 2.00 marked on crown the rings are also marked 2.00 my problem is all rings did not survive the removal did honda have a 2.00mm oversize piston and piston rings kit the cylinders 62.00mm  all the ring sets i find 1.00 os are the biggest listed if  you know where some rings could be found or made it would jumpstart the rebuild

Tim, I think that the old HAP JONES company offered a bunch of odd overbore pistons like that.

Honda only went for the std,.25, .50, .75, 1.00 sizes from the factory. I randomly see them on eBay sometimes.

The only other possibility to explore would be to see if the CB750 SOHC piston rings are the same width. CB750s are 61mm standard bores, so the full 1mm oversize would be 62mm.

Bill Silver

Motorcycle Repair

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Bill Silver


Need help with vintage Hondas from the 1960s? I am an expert with 250-305cc bikes in particular and most all of the other pre-91 models, in general. I do NOT claim to have a great deal of experience on Gold Wings, Cruisers, ATC/ATVs and dirt bikes.


I have owned/ridden/maintained Honda motorcycles for 35 years. I have written five books on Honda repairs and collecting. I was a service manager for two Honda shops back in the 1980s.

VJMC (Vintage Japanese Motorcycle Club) of North America

VJMC newsletter, as editor for two years and as contributing editor currently.

3 years auto shop in high school, teacher's aide in Automotive Technology in Jr. College, Diesel mechanic course in college, self-taught mechanic and automotive writer.

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