From: "Stoodley: Jon & Martha" 
Subject: Re: New Engine Break-In
Date: Mon, 30 Aug 1999 17:58:27 -0500

-----Original Message-----
Subject: New Engine Break-In

>I've heard the same new engine break-in procedure from the in-the-know
engine guys for the past 30 years:
>Three (3) engine heat up/cool down cycles initially for 5/10/20 minutes
>respectively.  Allow the engine to cool completely between cycles (the hard
>part!).  No lugging, heavy mud riding, or high rpm's during the cycles,
just
>"easy" going.
>Change gearbox oil to get rid of initial metal fines.  Re-torque head and
>cyllinder bolts.  Re-check coolant level.  Unbelieveably, lots of guys
>neglect these steps.
>The elite motorheads swear that following this procedure with no shortcuts
>results in motors with snappier power and (maybe) extended life.
>
>For what it's worth,
>Jon R.

This is essentially how we break in the MX bikes. I like to use 3 periods of
15 minutes each, gradually increasing the engine load. The cool-off period
is the key, you can't cheat- totally cool, otherwise hotspots will develop
and cause scoring/scuffing which may show up later. With the plated bores,
you are bedding in the rings AND the piston. With the type of rings used
now, synthetic premix oil is O.K. Change gearbox oil, check plug color (most
bikes are jetted rich from the factory), retorque  fasteners (all fasteners)
and coolant level.

OR, you can use the "quickie" run-in procedure the G.P. mechanics use (no
kidding) when changing top ends between motos. After assembly, remove
sparkplug, squirt contact cleaner in, replace plug, fire up and GO! (not
recommended unless you have factory backing and are in the points race).

Jon Stoodley
JSE Racing

ps, just got back from a week in Colorado, boy, you people sure got weather
better than Oklahoma at this time of year!