Rebuilding Top End of 570 Mtn Cat

[Frewsky]

I am rebuilding the top end of a 03 570 Mtn Cat and just wondering witch is the best way to put the rings on and were the gaps should be? I need some torque specs for the cylinders and head? Should I use the old gaskets or buy new ones on the head and the base of the jugs? Any other advice would be great!

 

[Rixster]

your pistons should have pins in the ring notches. Thats were the gaps go. Buy new gaskets for the base. If the heads are o rings you can reuse them, if they are gaskets replace them. Your torque specs are ( I am guessing) heads around 16-20 lbs and jugs around 35-45. Oil everyting as you put it together. The wrist pin bearing the pin the pistons the cylinder walls.
Also premix your first tank (or 2) of gas 100:1

 

[Frewsky]

Thanks for the info Rixster just need some torque specs for the jugs and head

 

[justindacey]

The ring-end gap should be 10-13 thou and the skirt clearance should be around 4 thou. On that little motor, the heads should be 16-20lbs and the cylinder base should be around 29-32lbs.

 

[diggerdown]

Also make sure you have the mark on the piston top towards the exhaust side. If you put the piston in the wrong way the ends of the rings will catch on a port.