Base Gasket leaked 
Then lost a ton of power and started to feel sluggish and making noise

Thinking I may have spun a ring?
Pulled head / jug today
Inspected piston and looks good with a good fit

Thinking rings
Standard piston
Measured the ring gaps
.0030 top ring
.0022 bottom ring

Seems unusual to have such a difference
Anyone have the Spec for these two ring gaps?
appreciate any info
 

How old are the rings. Gap is less important compared to how they seal at the ports. That's where they make or break the horsepower. Slide them one at a time down the bore exactly as they would sit on the piston with ring gap in close to the same spot in the bore & square them up using the piston. Then hold the cylinder up to the light & look for daylight around the ring. Slide it down from the top to about halfway between top & exhaust port. Anyway sudden loss of power could be loose carbon bits bouncing around in the muffler & restricting the spark arrestor. When you say base gasket leaked, it'd have to have sucked it in or spat it out around the sides to make it go lean & gasps & feeling like a loss of power. In my opinion that is & sometimes I wonder of course lol. Best of luck.

Thanks for the reply RD325

I think they are original rings and original base gasket
spark plug was perfect color
6400 miles, but not babied for sure

i did put just the rings in the jug and straightened them with piston but one at a time and measured gap but not at the same time. If this was a car the mis matched gap would be weird?


All else looks good, just these weird gaps….just wondering how you know you need to replace rings?


base gasket has been slightly blowing oil/gas near clutch arm recently, but just got worse on this ride so parked it. It was getting hotter than normal so that lean condition could be the culprit and not rings?

rod play feels good 

carbon in exhaust could be… I’ve not really focused on the pipe, but ordered new gaskets and will replace the rings with NOS if I can source. But if anyone agrees with the "gap don't matter" let me know...

thanks all
S

Yep i'd sure do rings regardless now its apart. Just unusual to "make a noise & lose power" without something showing like trying to seize the piston.

Offhand, those gaps seem pretty tight which can be a problem.  Someone could have put in new rings?   What bike is this on and/or how do the gaps compare to factory spec?

P.S.  The early Wiseco pistons were performance oriented and like many "racing" pistons came with rings that needed filing to the correct gap...  many people ignored this step and too tight a ring gap can result in seizure...  the nickname "Seize-co" was likely due to this...  One "fix" was shops would set up a Wiseco with a lot of extra clearance...  which opens up the ring gap...  when they could have used Wiseco specs and filed the ring gap to fit.  I remember filing Wiseco ring gaps...  it was nerve wracking for a kid without the right tools.  Or maybe the early Wiseco's were just crap?  I never had any issues but I knew a lot of people that did.  Wiseco eventually stopped supplying rings that needed fitting but you can still buy an older NOS Wiseco that might need ring fitting.

 

I'm so used to metric nowdays that i don't know how to read inches/thou. Do you mean 3 thou & 2.2 thou or 30 & 22 thou. Just thinking/wondering.

Here's a modern version of the exact tool we had at work which i probably used weekly until Japanese bikes arrived then that tool almost became redundant. That was going back to mostly 4 strokes so no stepped ring pegs to worry about on rings, just had to be flat ended & square on end to end.
Sorry, link didn't work i'll try again.

www.sulco.co.nz/PISTON-RING-GAP-FILER
Or one that would work just as good for a fraction of the price if link works.
Ebay 195124646042
Ok copy & paste into Ebay, cheap price.

RT325, that tool would have worked perfectly....  Not much filing was required so no concern about the step to clear the peg.  Gap out of the box was just a few  thousandths tighter than the minimum allowed spec. 
 

3 and 2.2 thou?
Way too tight.

cliff

Yep links were just for general interest. All good. Miss the plug sand blaster too, & a lot of other stuff we had at work.