piston/piston ring install - i want to learn

i'm ready to install my cylinder works big bore kit with wiseco piston & have a few questions.

go easy on me. it's been over 20 years since i've done a top end....and that was a 2 stroke.

i checked my ring end gaps.

bottom ring spec.: .0185" actual: .021"

top ring spec.: .0148" actual .0135"

the directions say the end gaps should be filed to get them parallel. they say to file only 1 end following the other.

the directios also say to use a special file - which i do not have.

my questions:

1) since my end gap is greater than the spec. on the bottom ring, do i file that ring?

2) is there any problems using a standard file or possibly an arkanas stone?

3) am i creating fractures in the rings by installing them in the cylinder to check the end gap?

i know those in the know here say not to re-use rings for this reason. is that only because the rings were in a running motor?

4) not real important, but i am curious - any reason why the oem piston has the thicker ring on top & wiseco piston uses the thinner ring on top?

Leave the bottom ring alone.

Top ring, you need to open it slightly. I use a Dremel with a cutoff wheel, clamped to the bench. Then I hold the ring square to the wheel, bring the ring ends together to just 'kiss' the sides of the cuttof wheel. A second od touch and re-check the fit.

Not fractures but in time if running, the ring develops wear pattererns that match the bore, nearly impossible to get the rings in the exact same spot, so you refresh with new ones.

where are you checking the rings at?used the piston to squared them up in the top 3/4 inch of the bore?

the ring gap being that far off doesnt right.

thank you for your help william & eddie :p

eddie - i can't recall for sure if i checked the gap with the rings in the top or bottom of the cylinder.

i think i checked them on the bottom of the cylinder. and i just squared them up by eye. i did move them around a bit & re-checked.

i will re-check them again as you mentioned.

if my measurements are correct, does the o/s gap on the bottom ring indicate a problem?

william - i appreciate the tips on filing the rings.

LOL, you must use the piston to square them up. Be gentle, take your time.

LOL, you must use the piston to square them up. Be gentle, take your time.

hey....stop lol'ing @ me :p

thanks again for your input.

yeah, i'm taking my time. i didn't have much time last night & was just getting a feel for things. spent most of my time measuring the big end side clearance, conrod deflection & conrod small end i.d.. all well within spec..

i've already learned a few things thanks to you guys.

i measure for a living. 20 years now. tomorrow night i'll be more thorough - mic the feeler gage, square rings up with the piston in the top of the bore as eddie suggested.

i rarely need to fit the end gaps and when i do its just becuase im ocd poster child.

i rarely need to fit the end gaps and when i do its just becuase im ocd poster child.

i suspected that most of these kits are installed as is without issue. not by you, but non-mechanics.

my ocd is what's keeping me from just slapping it together. that & i want to learn how to do it right, know what's going into my motor, and hopefully get it right the 1st time.

thanks again. i really appreciate the input :p

i re-measured everything tonight. assured rings were square in the bore. measured in multilpe areas top & bottom of cylinder.

pretty much the same as i posted above.

.013" gap on the top ring

.020" gap on the bottom ring.

the wiseco spec. is calculated. bore dia.x .004" for top ring & bore dia.x .005" for bottom ring.

that works out to the specs. i listed above(.0148 top & .0185 bottom).

bore measures 3.700".

my suzuki manual specifies .020" max for top & bottom.

i don't see a need to file, as the ends are parallel as is.

my only real concern is the .020" gap on the bottom ring.

my oem ring gaps were much tighter. .010" top & .013" bottom. all my oem stuff measured well within spec. - cyl. bore, piston dia., ring grooves, ring thicknesses, etc..

just thought i'd update. it's going to go together as is this weekend.

i foresee the oil ring being a bit tricky to get into the bore.

it will be fine.

thanks again eddie!

and excuse me for being so anal about this. and asking what are most likely dumb questions.

20 years of quality control changes a guy.

i understand completely.

thanks again eddie!

and excuse me for being so anal about this. and asking what are most likely dumb questions.

20 years of quality control changes a guy.

I love to hear that someone else has the same OCD problem. I spend hours just preping for most jobs....

Maybe if more people ocd we would have less crap on the market...

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