how are you breakin in your stage 2 cam and high comp piston

[YZROOSTINYA]

how are you folks breakin in your motors after top end rebuilds?

I know about keeping the r's above 3k for the hotcam for 20mins but what about the piston?


I was gonna run 10w-40 gn4 and after installing the cam and breaking that in I wanted to run the piston through some heat cycles. I was gonn ride it medium for 10 mins, let it cool completely. ride it agin another 10, let it cool completely. ride it another 10 about 3/4 throtle let it cool completely.

drop the oil and filter. ride it fairly agressively let it cool again and then that should do it right?


i have a je 416 with stage 2 hot cam. my motor was clean before the teardown and I lapped the valves to make sure there was a good seal. :square

my bottom end has about 50-60 hours on it

Originally posted by YZROOSTINYA



I was gonna run 10w-40 gn4 and after installing the cam and breaking that in I wanted to run the piston through some heat cycles. I was gonn ride it medium for 10 mins, let it cool completely. ride it agin another 10, let it cool completely. ride it another 10 about 3/4 throtle let it cool completely.

drop the oil and filter. ride it fairly agressively let it cool again and then that should do it right?



That's perfect..

[bmf400ex]

break it in like ur gonna ride. preferrably HARD!

[YZROOSTINYA]

if you ride it too hard during breakin you over heat the cylinder and you get galzing which is no good. you also need to heat cycles to cure or harden the piston to its shape. a new piston will distort if not heat cycled.

[Dune Surfer]

I just broke in a Hotcams & and JE piston. What I did was ride easy 10 min let cool being careful not to idle (turn up your idle screw) then ride 20 min let cool, 30 min cool 45 min cool 60 min cool. Change oil. I did this twice to be sure. after that let it rip

[YZROOSTINYA]

thanks fellas