Latest Questions on Engine Break-in

[Elmore]

Okay, its spring and I am about to break in my new DCS520i and I don't think that I will find another here in the states, so I want to do it in the most optimal manner. I looked at this site : http://www.mototuneusa.com/break_in_secrets.htm
and was wondering should I approach it as if on a dyno;
Warm the engine up
completely !! Maybe about 2 minutes or so.
Do three 1/2 throttle runs from
40% - 60% of your engine's max rpm,
let it cool down for about 15 minutes.

Do three 3/4 throttle runs from
40% - 80% of your engine's max rpm,
let it cool down for about 15 minutes.

Do three full throttle runs from
30% - 100% of your engine's max rpm,
let it cool down for about 15 minutes
Go For It !!
How long should these bursts of acceleration last? 10 seconds, 20, 30 seconds?
Or should I take it to the streets, get in the back of my truck while my driver accelerates, providing sufficient cooling air, while accelerating and decelerating saw, hard.

<img src="http://www.learnersonline.com/weekly/lessons03/week1/010603-5.jpg">

 

[sedanman]

Take the saw to the woods and cut with it. Don't walk from cut to cut with the throttle pinned but make all cuts at full throttle. It does not need to be any more complicated than this. The concept of a 'break in' proceedure is an old one left over from iron liners and iron rings. nikasil cylinders and moly rings do not need such babying. Run it like you'r gonna use it.

 

[jimbo1490]

Agreed. Chrome rings need a break-in. The best break-in seats the rings quickly. The honing on the cylinder walls provides a controlled amount of abrasion that polishes the ring faces. But before break-in the rings don't seal all that well. They seal better under pressure from engine load. If you baby the engine during break-in, blow-by may keep the rings from polishing out properly. Once the scratches on the cylinder wall (from honing) are gone, the rings are never going to break in, unless you re-hone.

With moly rings, it's a bit different. They finish honing for moly rings with 600 grit, sometimes finer. Sometimes they finish with a lapping or polishing step. With scratches this fine, there's little or no 'controlled abrasion' in a cylinder set up for soft moly rings, and they don't need it, so there's little or no break-in, either.

Jimbo