piston ring end gap spec

[timebombprod]

in the 650 service manual when you look for piston ring end gap it gives a serviceable limit instead of a spec that they should be between, the serviceable limit is .7mm and when measuring my piston rings that came with my bigbore kit i get a end gap of .165mm, my pistons are cast and i was told by the guy in the shop i brought my cylinders to that since i am using cast pistons i will want to be on the tighter end of the spec that the bike will like it more, well i dont have a spec to actually go off of lol.

got to see a barn find yamaha xs1 all stock with the yellow paint and a red kz900 with a exhaust at the shop i brought my cylinders to, real cool bikes.

[Grimly]

Rough rule of thumb, iirc, is 4 thou per inch of bore for the gap, subject to a maximum as in the service manual.

[timebombprod]

what do i go based off of though? all it tells me is when to replace the rings but i dont know what the clearance is on a new motor and id like to go based off of that.

do i go off diameter or ci for that rule if theres no spec? my cylinders are 185 cc each.

[Grimly]

Bore diameter, in this case, inches.

[timebombprod]

i cant seem to find my tape measure but its about 2 and a half inches in diameter so itd be .001 but how do i use that when i dont know the normal end gap clearance? i wish there was a stock spec i can go off of but i cannot find an actual spec they should be between on the oem service manual.

[hank2]

timebombprod, if you're referring to your Suzuki GS650GL, the bore is 62 mm. Which would be approximately 2.44 inches.

[Rich82GS750TZ]

Cylinders have been over-bored. See post # 1

[hank2]

Cylinders have been over-bored. See post # 1

Ahh, missed that. So 2.44 inches plus amount of overbore in inches.

[Agemax]

A quick look at the FSM on Basscliff's website shows these specs for the rings......

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[Cipher]

Contact the Manu. of your bore kit. Iirc my wiseco set has different req. than oem.
must install them someday or do the Millyard youtuber hack saw it into a v8

[Grimly]

2.5" would give about 10 thou, not 1. This is only a guide though, it's not set in stone.
Could well be the makers have specified a different gap.