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top end rebuild

  1. 400ex new top end break in process

    I have a 2002 400ex and recently did a top end rebuild. I put in new rings for a 416 piston and new rocker arms. Seals and stuff too. I have already let idle For 20 minutes, cool. Then 1/4 to 1/2 throttle variation for 20 minutes, cool. What would my next step be to break in the new rings?