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Just a couple of things:
If the temperatures attained during boundary lubrication conditions (since they will never be this high during hydrodynamic operation) of the cam lobes, bearings, etc, are high enough to cause a metallurgical change in the parts, they will be junk. No heat treating can occur in a running engine. The temperatures to make these changes are at a minimum 600 degrees F.
Next, the "scratches" in the cam lobes, gears, cylinder walls, etc.. are all vital to hydrodynamic lubrication. The metal parts are not designed to ever touch, only ride on a film of oil between each other. The scratches or grooves act as reservoirs for the lubricating oil. During run-in, the tips of these scratches or grooves are flattened into plateaus, which allow for more bearing area on which the oil can "spread out." (results in less stress on the oil film.) This is the only concern re: break in, the formation of these plateaus. High loads on the gears, whether during accel or decel, could cause tearing of the surface rather than conditioning (this being pure speculation on my part)... this was once true for the cylinder walls, but I have to assume that Triumph is in the 21st century with the rest of us and uses plateau honing, which makes the formation of the plateaus by riding the bike a non-issue. I was talking with some guys from Ford (heh) a while back and they mentioned that there was a plateau honing type operation in use for gears at this point, I'm unsure as to what gears. (Auto transmission, rearend...??)
Some folks will mention rod side clearances, but that's actually checked these days and the finish is pretty good. If you're rubbing hard enough to remove metal you're in big trouble. I re-read the first post and it mentioned springs, the only thing I could find on that is one heat cycle before high rpms is a good idea; this probably happened at the factory or the dealers (where, regrettably, the rings were seating at idle.)
You can take my advice with a grain of salt, or even talk to some engineering type folks around it. I've just read a few white papers and talked with mechanics who work on machines that cost 100's of times what these bikes do. An engineer told me once that the ideal cylinder wall condition is "perfectly smooth." and that the only reason that they're not manufactured that way is excessive machining costs. Even today, it's tough to get the right information.
If anyone can add to what I've written go ahead, I'm always open to new ideas.
edit: my break in procedure:
Warm engine before heavy loads, Moderate to high cylinder pressure (load), vary rpms (redline ok.) oil change after the first couple of rides and then at 200 kilometers or so (machining/clutch residue and the aformentioned plateau peaks!), synthetic at the first scheduled change. Try to stay out of the rev limiter, esp. on carbed bikes. Never lug the engine, old or new.
I think that you have to try pretty hard to spoil an engine during break in, and the worst thing to do is idle around. So hit it hard, you only live once, and I hate the prospect of my machines outliving me!
[ This message was edited by: eighty6gt on 2006-08-08 22:50 ]
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