Need help with 1397 kit piston ring gap

KYBUSA502

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Long story short I bought A.P.E's 1397 piston kit 13:1 for my gen 1 busa. I need to know if the rings come ready to install or do I have to gap them. the rings came with the kit and I know most of you will tell me to check it with a feeler gauge but on the chart specs it says Bore x .0045" for the top ring. now what does that mean on a feeler gauge?? I'm lost and I suck at math. is this kit a plug and play or do i have to file the rings myself. I'm running a all motor setup no nitrous no turbo. please help this is my last problem holding me up!
 
1st measure all of gaps espacially for (in) the cylinder you wanna put em in
the how-to is described i the manual
but please get for that 1/100mm based feelers but no inch ones
in that very small values the inch is less precise, i guess

then my thought was to spec (file) the ring gaps like said in the manual (tolerances) and the standard rings
if the gap is to small it will cause issues at the cylinder "wall" what would destroy the cyl.

and watch the mounting points of the gaps when setting the block
the "mercedes star" is a good example. ;)
 
1st measure all of gaps espacially for (in) the cylinder you wanna put em in
the how-to is described i the manual
but please get for that 1/100mm based feelers but no inch ones
in that very small values the inch is less precise, i guess

then my thought was to spec (file) the ring gaps like said in the manual (tolerances) and the standard rings
if the gap is to small it will cause issues at the cylinder "wall" what would destroy the cyl.

and watch the mounting points of the gaps when setting the block
the "mercedes star" is a good example. ;)
Thanks i appreciate you taking time to reply. i have to get a ring filler now and i will do.
 
Thanks i appreciate you taking time to reply. i have to get a ring filler now and i will do.
Did you end up filing your rings? I have same issue with new JE rings. The top compression ring has too small end gap compared to JE own street bike specs "bore x .0045" (0.38mm) current gap is 0.25-0.30mm
But compared to stock ring specs, the end gap is big.
 
Make sure to only file one end of each ring too, and slowly, it's easy to remove too much material if you're not careful.
Thanks. I am really torn between filing rings or leaving as is. New rings are installed due to old rings did not seat/ low compression/ exseccive blowby. Bigger end gap will cause lower compression? I didnt file old rings and end gap where "too small" as well but they came out in one piece..
 
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