any piston break in suggestions

[kenny]

any suggestions on break in.going to dumont dunes thanksgiving wont have together till wednesday.need to be ready for hard dune riding weekend.whats your suggestion for a proper break in

[cals400ex]

check this thread out:

http://www.exriders.com/vbb/showthread.php?threadid=75157&highlight=break

[Geoff Thomas]

Take it easy on it for a tank or two of fuel. Also it is a good idea to start it up and let it warm up completely then shut it off and let it cool completely. Don't just let it sit there and idle though. Kinda vary the rpms and blip the throttle ever so often. Don't rev the piss out of it either. Do that 3 or 4 times and then ride it easy for a tank or two and it will be good to go. Also after you brake it in change the oil and filter right away. If you put a new cam in it (you should have put new rockers in it as well) you need to let it rev at 2000 rpm for about 15 min to brake the cam in. There should be instructions on this in the package with the cam.

[DamageInc]

I break-in my bike and sled engines basically the same as motoman:

http://www.mototuneusa.com/break_in_secrets.htm

[Geoff Thomas]

I'm a firm disbeliver in that method of running the piss out of anything to brake it in. I have seen studies on Lightning trucks that if you brake them in nice they make more power. Also the manufacturers have spend countless hours and money testing on this and I gurantee that they have way more invested in the engines and testing than that guy does. Weather anyone wants to belive it or not the manufacturers know their stuff and the parts/accessories/lubricants etc. that they produce are probably the best you can get over aftermarket parts. If the factory made all the aftermaket hop up parts for a bike I would go there first before I ever bought aftermarket stuff. That is why I will be getting the HRC power up kit for my new TRX450R as soon as it gets here.

[DamageInc]

The reason why the manufacturers tell you to take it easy, is because there is a fine line between running it hard enough to get good break-in (adequate cylinder pressure) and running it WFO for too long and causing damage. There is extra heat generated during break-in, which is why you shouldn't do long wide-open runs, but you do need short full throttle bursts to get adequate cylinder pressure. The manufacturer is only worried about warranty claims during their warranty period, not about you having peak performance or the longest possible service life. Surprisingly, Arctic Cat actually puts in their owners manuals for sleds that short full throttle bursts will contribute to good break-in.
This link explains it pretty well: http://www.ntnoa.org/enginebreakin.htm
Even airplane builders recommend the same thing: "Low power for break-in may result in glazed cylinder walls and high oil consumption that can only be cured by cylinder removal and rehoning."
textron (http://www.lycoming.textron.com/main.jsp?bodyPage=/support/publications/keyReprints/operation/lowPowerLowRPM.html)
Motoman calls this a "controversial" subject, but it's only controversial to people who are stuck in an old school way of thinking. I've been an ASE certified tech for over a decade, and I was originally taught the old school way in tech school, but I have since become better informed on this subject. The key is SHORT full throttle runs to avoid excessive heat, and no extended WFO runs for the first few tanks of gas. You just can't get adequate cylinder pressure by babying it. Do a google search on this subject and you will find a ton of people who agree with me.