compression increase during kit break-in?

does this sound unreasonable?

ive got about 25 miles on this kit. when i first tested it warm it was about 155. now its in the 175 area. that seems like too much of an increase. inaccurate gauge, or does this sound normal?

Re: compression increase during kit break-in?

New rings don't seal well. They wear down and the compression goes up.

Re: compression increase during kit break-in?

▣ß@ηℊℙℐṔ∃▣ ™ /

mine was about 13 increase

Re: compression increase during kit break-in?

clarification: i expected a modest increase as the rings got seated. 20/25 psi is way more than what i expected.

Re: compression increase during kit break-in?

Sounds normal to me, but then what do I know? Of course the break in part IS the seating of the rings and makes sense that compression went up. It could be that your old ones were so worn that they were loosing some compression. If it still runs great and doesn't make any funk noise, then you should be good. Just be gentile till it's broke in.

Re: compression increase during kit break-in?

carbon build up dude, its fucking great, stop cleaning your piston crown/compression zone

~SABAT!

Re: compression increase during kit break-in?

carbon does not raise compression.

but the rings sealing perfectly to the cylinder wall does.

Re: compression increase during kit break-in?

my gauge is a cheap harborfreight one. i acnt vouch for the overall accuracy, but at the very least it seems to be consistent in terms of the readings it does take. im pretty excited about compression being just south of 180 psi.

been having some problems of late with really low idle, despite having it set to idle high (idles high when cold, too low when warm). kit finally died last night and i took out the plug and it was real lean. thought maybe it was my decomp valve (moby 50v, malossi 62cc), but compression immediately after was 175+, so i doubt it was the valve). still going to pull the cylinder and check, though.

Re: compression increase during kit break-in?

sounds totally normal.

Re: compression increase during kit break-in?

cool. thats what im wondering. thanks peter.

Re: compression increase during kit break-in?

if it doesn't increase by that much something is wrong.

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