Topic: .75 overbore pistons with standard sleeves?

[nickbee]

Will .75 overbore pistons work with standard sleeves for a 69 - 76 SOHC CB750?

Thanks!!!

[oldbiker]

If you mean 'will the pistons go straight into the standard sleeves,  NO.  The standard sleeves were designed to have enough thickness to allow for overboring to accept + size pistons but you must have the sleeves bored and honed to accept them.

[Tim.]

The short answer is yes, 0.75mm overbore is well within the limits for the existing cylinders.  Honda in their own parts manuals listed pistons/rings for these bikes up to 1.0mm overbore, so you'd be able to bore one more time and still be within spec.

Overbore kits often go up to 3.0mm overbore without new sleeves.  So, you can go beyond 1.0mm without too much issue.

So go get your pistons and have the cylinders bored.  Just remember the machinist needs the pistons to do the bore.  They should measure each piston and bore the cylinder to match that particular piston.  Every piston is slightly different.

[nickbee]

Thanks Tin Tin, that's the info I wanted to know.  Anyone know a good machine shop in Northern, NJ?

Thanks!