belltold12 said:
you should give this a once over. it might be too late depending on how far along the break-in period you are, but for future reference it's definetly something to consider.
http://www.mototuneusa.com/break_in_secrets.htm
hahahah i love it every time that stupid article comes up. motomoron is just that, a moron. i read that article and doesn't know jack squat about what he's talking about because the article glosses over important details.
motomoron writes: "If the rings aren't forced against the walls soon enough, they'll use up the roughness before they fully seat."
yay! this is quite correct. he is not a moron after all. so let's get those rings pressing hard against those cylinder walls soon.
motomoron writes: "How Do Rings Seal Against Tremendous Combustion Pressure?? From the actual gas pressure itself!! It passes over the top of the ring, and gets behind it to force it outward against the cylinder wall."
yay! correct again. not bad for a moron. so let's make a lot of cylinder pressure to get those rings pressing hard against the walls.
so what does motomoron suggest for a practical implementation of all this excellent wisdom?
motomoron writes:
1. 3 runs 40% - 60% of the engine's max rpm
2. 3 runs 40% - 80% of the engine's max rpm
3. 3 runs 30% - 100% of the engine's max rpm
so do these actions actually implement the excellent theoritical wisdom we were just imparted? only if you're dumb enough to think that cylinder pressure is proportional to engine rpm. alas motomoron is, in fact, a moron after all.
so how do you get high cylinder pressures to force those rings aginst the cylinder walls? answer: hard acceleration against a load (going up a hill, for example). there's no need whatsoever to use high rpm to generate high cylinder pressures
but is reving the bike to 100% of the engine's max rpm really a bad thing to do on the 7th - 9th runs of a new engine? yes! bad! it is the worst thing you can do. why? because the higher you rev, the higher the piston velocity and high_piston_velocity = bad. why is high piston velocity bad? because it will glaze the rings. you've heard that before, i'm sure, but what does it mean "glaze the rings"...?
the following experiment is an analogy to engine break-in at low rpm (good) and high rpm (bad):
imagine you have a variable-speed grinder with a fine-grit grinding wheel attached. you also have a piece of soft plastic in your hands. turn on your grinder at a slow pace of 500 rpm, and start grinding the plastic. it grinds away nicely leaving your plastic in the shape of the grinding wheel-- the surface of the plastic does not melt and therefore the plastic surface has the same properties you started with. now increase the speed of your grinder to a ridiculous 12,000 rpm and start grinding your plastic. if you've ever tried this, then you know what happens: the microscopic outer layer of plastic melts and glazes forming a very hard and brittle outer shell covering the soft original plastic core.
if you didn't realize the first time around, the fine-grit grinding wheel is your honed cylinder wall, and the plastic is your piston rings. break in your engine at slow rpm using acceleration and engine loading to obtain high cylinder pressures!
