seized piston from correct jetting?

[bige]

this seizure wasnt from a kx but from a ktm 105. the crank bearing seized from to little lubrication and beign ran very hard in a race, so upon cutting the base of threads off spark plug to see the mixing ring at the base and to my supprise the whole porcilan was light brown and a small black ring at the base. from what i have studdied about plug reading if there is a black ring at the base of plug even if the rest of porcilan is solid white them its running to rich, well im second guessing this now. this bike was stock jetted altitude 2000ft 80degrees temp and 93 octane fuel mixed with klotz supertech at 32:1 and had no cooling failure, so apparently this wasnt running quite rich enough contrary to reading the plug mixing ring. the piston crown was all black no wash at all and the under side was burnt dark brown to black.

[cbxracer30]

I think you are digging way to far into this bearing failure , more times than not its just plain bearing fatigue on the small high revving motors , also check the lower rod bearing for signs of over heating .CBX

[bige]

this motor was completely dry rod, bearings, piston, spark plug etc. this had no fuel mixture lubrication any where, it ran hot and dry, thats why i was so suprised to see the plug color a light brown but still seized.

[cbxracer30]

Was this a too lean condition due to the wrong jet or a lack of lubrication condition due to say someone put the wrong fuel in the bike [ straight gas -no 2stroke oil in it ] ? CBX

[Polar-Bus]

this seizure wasnt from a kx but from a ktm 105. the crank bearing seized from to little lubrication and beign ran very hard in a race, so upon cutting the base of threads off spark plug to see the mixing ring at the base and to my supprise the whole porcilan was light brown and a small black ring at the base. from what i have studdied about plug reading if there is a black ring at the base of plug even if the rest of porcilan is solid white them its running to rich, well im second guessing this now. this bike was stock jetted altitude 2000ft 80degrees temp and 93 octane fuel mixed with klotz supertech at 32:1 and had no cooling failure, so apparently this wasnt running quite rich enough contrary to reading the plug mixing ring. the piston crown was all black no wash at all and the under side was burnt dark brown to black.

Crank bearings do not sieze from incorrect (lean) jetting. Piston crowns melt from incorrect (lean) jetting . The only reasons crank bearings  fail  is from dirt intrusion from a dirty air filter, or rust pits on the bearing balls from inadequate extended engine storage.