Stu Fields wrote:
"Anyolmouse" wrote in message
...
Anyolmouse

What kind of TBO is expected @ 12,000 rpm?? Some guy who has been playing
with engines for quite awhile has a rule of thumb that says 4500 is a kind
of mark for piston engines beyond which the durability starts decreasing
more rapidly??? I haven't double checked this, but it makes some sense that
the faster the piston engine spends the quicker it wears. There is several
projects using the Yamaha 4stroke snowmobile engine that turns up around
12,000 for it's hp. Data should be available soon on their durability...

true for cast-iron cylinder barrels, not true for diamond-like hard
modern coatings.

here's a pic of the engine:
http://www.ph21.de/guest/1000RR.jpeg