Do u guys know if i need to do a top end rebuild if i plane to replace only pistons/rings for the first time on my 95 sn sj. The head has never been pulled. The oem pistons have a good amount of carbon buildup. i'm doing some other mods (new head, bpipe). It ran fine before i pulled the head so maybe nothing needs to be done. 150 psi both b4 pulling head.:sneaky:
carbon buildup on pistons
- Thread starter Pablo
- Start date
thegoldenboy
RN Surgery... soon
- Location
- Toronto
Don't touch them. Buildup is normal, I'm sure its in better shape than you think, you're probabaly not used to it yet. Pistons can be pretty dirty and still in great mechanical condition.
WAB
salty nuts
- Location
- coastal GA
carbon on the piston crowns in a 2 stroke is not a big deal like carbon buildup in a 4stroke. WD40 will clean the carbon off pretty well if it bothers you.
However, with increasing compression on a possibly 13year old motor, you may want to pull the cyl and run a hone through it and put new rings on the pistons.
However, with increasing compression on a possibly 13year old motor, you may want to pull the cyl and run a hone through it and put new rings on the pistons.
thegoldenboy
RN Surgery... soon
- Location
- Toronto
How do you kinow the head has never been pulled? Unless its been in the faimly for years I wouldn't believe anyone.
I was told that when I bought my 650SJ. Pulled the head, pistons said 0.75 on them... who can you trust.... :grouphug:
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
most yamaha head bolts are painted, you can see the paint missing if the bolts have been removed.
this ski is 13 years old, it is time for a rebuild...........
this ski is 13 years old, it is time for a rebuild...........