What's the situation with breaking in a Zenoah G260 engine. How long is the process, what revs, etc. Thanks
Brandon.

I broke my engine in by running a slightly rich needle for the first few tanks & running it at 3/4 throttle in the straights & backing off in the turns to vary the speed & heat in the engine. After a few tanks & tuned it to run on pipe & just ran it. It will loosen up over time & may take a gallon or so of fuel to do this. It is often recomended to run the first few tanks through using a mineral based oil to seat the ring before switching to a good synthetic oil. I personaly have only used Castrol A747 (which is designed for high revving cart engines in wet condtions) in my engines for running in & racing, but I understand they have discontinued that line in the states.

We don't worry too much about break in except to be sure the needles aren't too lean. We run our standard 8 oz of oil per gallon. A couple of dyno runs seats the ring, but the crankcase seals seem to take a while to break in. Low drag seals are the solution there. Break in does increase the power. In a series of recent dyno tests we saw the top end power increase significantly over a series of more than 50 runs. See the graph below.

Lohring Miller

Thanks for the help.