I own a 2003 YZ125, and I'm thinking about wheather I should have a big bore kit installed. I was reading on Eric Gorr's sight, and he explained that the 144 requires maintainance at 5 hrs. for rings, and 10 hrs. for the piston. Is this also true for the 134 kit? I don't race, and I ride just on the weekends, and I have been redoing the top end at 40 hrs. What is the recommended maintainance for the 134? Thank you.
YZ125 to 134 or 144?
- Thread starter RJGoonie
- Start date
I get the same hours on my '06 YZ 125 eric did as a 144 with the higher compression race gas head mod's. In fact the 2 nd piston went the 40 hrs re- ringed it and got another like 15 out of it. Oh ya thats mostly moto time also you ride trails so it will be even more reliable without the high compression head mod's and milder porting. 144 it and go up 1 tooth on the front it rocks in the woods.
robwbright
Member
- Apr 8, 2005
- 2,283
- 0
Eric recommends those times, but he has had experts blow a 144 in an hour and he has also had one 144 go 100 hours on the same piston.
It just depends on how hard you ride it - how much over-rev, etc . . .
It just depends on how hard you ride it - how much over-rev, etc . . .
Oh the first piston I got 40 hrs on it and replaced everything and I think i'm going to stick to that this time around again and not push my luck. I just took apart this last top end where the piston went 40 hrs and it looked good at the time and just re- ringed it and ran it for at least another 15 hrs.
Well let's just say i'm rather glad I quit when I did this time cause it had a slight sieze mark on the lower part of the piston skirt from the exhaust bridge this time around no mark on the ring. Just lets me know I'll have to do the whole thing everytime around 40 hrs. BTW i'm not very easy on my bike I do rev it up pretty good but I keep it away from constant over revving whenever possible. Of course my clean air fliter every long ride or two short rides has really helped out.
As far as damnage to the cylinder there was none. I kinda pushed it alittle far this time on purpose to see how much wear I could get now I know.
Well let's just say i'm rather glad I quit when I did this time cause it had a slight sieze mark on the lower part of the piston skirt from the exhaust bridge this time around no mark on the ring. Just lets me know I'll have to do the whole thing everytime around 40 hrs. BTW i'm not very easy on my bike I do rev it up pretty good but I keep it away from constant over revving whenever possible. Of course my clean air fliter every long ride or two short rides has really helped out.
As far as damnage to the cylinder there was none. I kinda pushed it alittle far this time on purpose to see how much wear I could get now I know.
