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Old 08-25-2008, 05:49 AM
Bikeguy Joe Bikeguy Joe is offline
Godfather of Motorized Bicycles
Join Date: Jan 2008
Location: up north now
Posts: 11,531
Default Re: How long (miles/gas) should breakin take

Normally 20:1 is more than enough (modern) oil for break-in.

I run 24:1 afer that for the engines since I don't take them apart and mic the wristpin, which always seems to be on the loose side.

32:1 is O.K. if you run full synthetic and don't rev 'em up too hard.

Run a tank of 16-20:1 then go to 24:1 for a couple hundred, after that you are on your own.

Break-in of the rings (also called "seating" happen very quickly once the engine is started.

The best proceedure for seating the rings is to fire up the bike, warm it slightly, then ride it varying the throttle postition and engine rpm contantly. Generally, you want to accellerate for 10 seconds, then back off a little and SLOWLY de-cellerate for 10-20 seconds, repeating this cycle for several minutes, each time with slightly more throttle so in the 10 seconds, your rpm is higher each cycle.
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