When i put my top end back together for my 97 scrambler bored .40 over with new piston and rings, is there any assembly lube i should use to protect the cylinder from scratches? Any other helpful hints on the top end rebuild would be appreiated also. Thank you!

 

yes it wouldn't hurt anything to be use a good preassembly lube. make sure the rings are set correctly and piston is facing right direction. imo

 

don't laugh, but i used 2 stroke oil as assembly lube when i put my 400 2 stroke back together

 

Thats fine! thats what it uses any way and its usually what I coat a 2-stroke cylinder with on rebuilds. OPT

 

 

How can you tell which direction is " Correct" on a aftermarket piston?

 

markings either go to magneto side or exhuast side. just depends on where the markings are

 

Isn't there a arrow or line on the top of the piston? If so, the arrow or line faces forward.

If not...the manufacturer should have given instructions on proper placement.

 

i figured it out...hopefully. The intake values are bigger than exhaust...so the cuts in the piston are bigger also. I read the instructions and the service manual, they stated that the arrows or dots face the exhaust but that put the piston perpendicular to the wrist pin mount. So i figured it out the valve clearance way.