Piston brand identification.

swest wrote: Gas porting was done around the tops of the piston to force the rings out for a better seal. Never had the nerve to try it though. The holes on the sides are for more oiling.
Steve

My understanding is same. Gas porting holes shown in this photo. Those holes under the oil ring is to allow the oil scrapped by the oil ring to get off the cylinder wall and I think those holes are stock for those pistons.

I guess I looked at the ring lands and figured the tops were done also since they went to the trouble to do the bottom side without looking closer. :S :lol:

Well the plot thickens, the stuck ring was caused by a cracked ringland, or vice versa.
Either way my wallet takes a hit that it's not prepared for.....

I was able to read the full number on one of the other pistons. "4135"
So, 72mm bore, wiseco 4135.
Not coming up with mich on a google search, does this ring any bells with anybody?
Any info is welcome, I need to figure out my next move.

I hate to tell you, if they are cast pistons, Wiseco doesn't make them anymore. I needed one but had to buy all four at $500.
Steve

MadShad wrote: Well the plot thickens, the stuck ring was caused by a cracked ringland, or vice versa.
Either way my wallet takes a hit that it's not prepared for.....

I was able to read the full number on one of the other pistons. "4135"
So, 72mm bore, wiseco 4135.
Not coming up with mich on a google search, does this ring any bells with anybody?
Any info is welcome, I need to figure out my next move.

You may need to call Wiseco direct.
I needed rings once while doing a top end freshening and couldnt find rings for my 1075cc motor. I called the factory and they said they had redesigned the pistons which now called for a redesigned ring as well. They had me send them my pistons and replaced the pistons and rings for the cost of the rings.
It cant hurt to call. You never know what they may do for you.
In regards to the drilling of piston tops for gas porting it has been my experience that those little holes become plugged
pretty quick ,so unless you plan on tearing it down all the time like a race motor shop does I wouldnt bother.

Worth a shot.
Steve

They were helpful in finding out what I had, but had no interest in selling me just the pistons and wrist pins. (i have everything else, assuming I'm able to stay at 72mm bore)

Thanks for the help guys, I now know what I have.

I'll be taking advice and posting progress in this thread.
www.kzrider.com/forum/2-engine/602856-lo...-breather-kz900-1000
Waiting in bore measurements, should have them tonight.