Carrillo pistons and rings.. Not sure my ring and gaps were set properly.. I fit them in the cylinders and have .026" on both first and second rings as well as front and rear cylinder. The service manual calls for to ring 0.0012-0.022" and second ring 0.015-0.025"
Now in the past I've always set it to .0045" per inch of piston.. Should I wait to install and call Fuel Moto on Monday? I got this 110"kit from them.. I think they are way too big.. Thanks..

 

I wouldn't go off info from the service manual, different pistons

But, .026 sounds loose for the top ring, fine for second ring. Supposedly FM presets the gaps...

 

Yes they did set them.. Never seen top same as second ring.. Not sure if they set them like that because static comp is 11.23: and corrected for cam timing will be will be 10.17: with a ccp of 216 psi... What sucks is that I cannot call them on a Saturday...

 

I sure would not worry about it. But just an opinion. Your .001 over on one and that virtually impossible to measure with a filler gage. My guess is they made them on the safe side for a hot motor. .004 is the thinner the two loose leaf sheets of paper.

My guess is they fill they are not worried about a Harley spec. Harley wants a long motor life from their factory stuff. Cars need to maintain emissions control for what, 8 years and 100k in CA.

Not sure we're Harley must be since is considered sport utility for emissions.

 

The Carillo pistons are forged so don't they require a larger gap than a cast piston? I'm right in the middle of putting together a 110 kit from fuelmoto. In fact I just got the heads back last week. I already have the cylinders on but from my notes I have basically the same numbers as you as far as ring gap goes but a little tighter...sure hope they're good lol. Hopefully someone will have a better answer before Monday...was hoping to have this guys motor back together this weekend.

 

I use Go-No-Go gauges so yes you can get pretty accurate..


Yes forged require more cylinder clearance than cast..

I'm sure Fuel Moto has a lot of experience with these 110" kits so it just might be by design.. look at it this way with a liner thickness that's 1/2 of what a stock 103" cylinder is @ .130" and what I measured the 110" cylinder sleeve at .066", maybe there's more expansion (growth) of the cylinder which would close down on the bore a little more requiring the bigger gap.. We all know how hot these twin cam's get..

 

Even if they want the gap looser (.005" per bore inch is CP min spec for turbo application) the second ring still needs to be larger than first. Just because FM set the gap and has done tons of kits doesn't make them inhuman

 

True..

 

I could probably get an answer for you shortly.

Its on the high side for the top but Don said he wouldn't worry about it. Leave 'em be he said. The second is where it should be and no reason to go bigger just because the top one is on the high side.
It's your baby. Just thought I'd ask him since I was calling him anyway. Take it for what it's worth.

 

Thanks..I appreciate you looking in to it.. I'll go ahead and assemble..