Re: break in period

["Christopher Morgan" <cmorgan02@sprynet.com>]

Here's more info on breaking in German engines that just popped up on the
Honda Hawk GT (motorcycle) list...
(MCN = Motorcycle Consumer News)
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        I know many of you have heard this but if not, it is worth
repeating.
Fred Rau of MCN was speaking at the AMA Vintage Bike weekend at Mid-Ohio
this summer.  Someone asked him about long term observations on the BMW
oil-head boxer engines.  Fred said that much to they at MCN had heard
reports of riders getting more horsepower and higher gas mileage on these
motors after putting 50,000 miles on them.
        At first the staff at MCN thought these were fluky stories,
inaccurate,
and incredible.  But these reports began to multiply, so they brought in
some high mileage examples for testing(some of the very same bikes MCN
tested new) and found that these motors did indeed produce more horsepower,
get high gas mileage and have higher compression than they had in their
first year of service.
        Why?  MCN surmises that the tight tolerances and nickel-silicon
coatings
in the new engines require as much as 50K miles in order to break in and
seat the piston rings properly.
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OK, the extended break in period of these bikes is most likely due to the
Nikasil coating in the aluminum cylinders, which is extremely durable (that
is, until you put high sulfur content gas in them, just ask anyone who has
had their engine replaced in their 530i/540i).  What the post doesn't state
is that a lot of these riders use synthetics or blends (Spectro-made oil in
particular) and changed their oil at the 600 mile (1000km) service.  Also, a
lot of the bikes had very high oil consumption until the they got a bunch of
miles on them.  My ex-K75S was still sucking down 3/4 quart every 500 miles
when I sold it with 15k on it, and I had done the synthetic at 600 miles
thing.

Chris