Boys...I've Got Me A Rattle

[Jason2tpa]

I still think you need to get a stethoscope to listen to your motor

Oops, forgot about trying this ^^^ before removing flywheel. Thanks for bringing it up again.

[zenoahphobic]

Be careful because you are suspecting something under the flywheel, not actually place that stethoscope too close to the flywheel. I'm having nightmarish visions of your head been wound into the flywheel. (Any mechanic prepared to devulge that happening to them? Maybe winding up some instrument).
Townsville's previous post reminded me what a great source of learning working on motorcycles is. He had a roller bearing not fail, but I would say worn out/ end of its life at 32 thousand miles, Twice.
The type and location may have predicted this, and replacement carried out before it happened again.
The learning is that sealed bearings don't last as long as constantly oiled bearings.
And bearings near flywheels have a hard life, beit from unbalanced concentration of mass, the giroscopic forces produced, or the improper use of a roller bearing without adequate side thrust protection (backlash shimming?) etc.

Roller bearings "grind" more on the separation cage, and when becoming suspect emit sounds readily because there are greater surfaces turning against each other (outside roller surface travels faster than the inside surface).

[zenoahphobic]

You know technically there is a reason why things fail.
That is a ball bearing that has a greater tolerance for side thrust than a roller bearing; but.

Motorcycle engines do have to operate at tilt positions that not only affects the side thrust (front and back) but also from the affects of oil moving from side to side.

The bearing needs to have constant lubrication and may have no forced lubrication to it. Bearings have not only limits on the load they carry but also limits to the revolutions that they can run at.

The difficulty with deciding on the bearing is that a larger bearing can withstand a higher load but the internals travel faster than a smaller bearing creating more load (bigger bearing means bigger balls means greater outside diameter, means greater speed difference, means greater slipping of balls on the surfaces means friction...)

I guess that bearing was used to balance its reliability to it's life. The engineers probably felt that 32,000 miles was a good enough life. But often this is not a good look to advise the changing of this bearing as part of a maintenance schedule as this would be considered as a major overhaul these days.

[99yam40]

I road a Kawa 1000 down the beach once many many years ago
spilled my beer when I tried to turn it around on the sand

[zenoahphobic]

I road a Kawa 1000 down the beach once many many years ago
spilled my beer when I tried to turn it around on the sand

We have hats with built in two beer containers with two straws down to your mouth, difficult to spill much and leaves your hand free to hold a cigarette or to solute the crowd with.
Nowawa days they are more discreet they call it a hydration pack.