frequencys of oscillations & materials influance theyre patterns of responce . Incompatable Vibes ( distortions ) would be cumulative . hence the B A N G .
" A Superblend is basically a roller bearing, but actually, its a barrel-race bearing. The 'rollers' are beer-barrel shaped and thus provide a broader surface of support than a simple ball bearing, whilst allowing for flex in the shaft they are supporting, a thing a plain roller can never do until it fails. Two Superblends offer nearly as much flex as the original ball/roller combination, but they also allow for uniform flex, along the length of the shaft, rather than isolating it towards the ball bearing end of things, like the combined bearing setup does. "
from our good friend , D.J. Walker .
" I'd think so, but if the crank gets really out, I've seen the roller bearings shatter their races. They can only accept so much runout. XR750's use those barrel shaped superblend bearings, to accept any deviations without incurring excess drag. "
Mr Hightop , from M D .
Barrel roller bearings are single row, self-aligning roller bearings. They comprise solid outer rings with a concave raceway, solid inner rings with two ribs and "
have a read .
http://www.m3.tuc.gr/ANAGNWSTHRIO/STOIX ... ARINGS.pdf
DUNSTALL ball races were the Deep Groove high capacity type . The high capacity deep groove , kept the ends of the cranshaft in alignment.
Unfortunately the main crank assembly still flexed , breaking off the mainshafts from the webs. Despite the cases ' flex ' .
Going from one extreme to the other , at 7.000 cycles a minute , ( or 7.500 ) apparently created some cumulative loadings .
Intrestingly , the std. ' ball races ' have a lower drag , thus less impediment to output.
However , unless you replaced them before theyre service life expired ( they failed , or started to produce high tensile steel ' Debri ' ), it would get expensive .
For a ' sprint ' 750 ' that is etting overhauled / stripped , at regular intervals , it could be worth useing them for the horsepower advantage .
Youd go through a fair stack of them though . & gasket sealant etc .
tecnically , its not really flex or whip , though theyre close . it osscilates about the axis of rotation . Probably the thrust a peak bmep period of rotation being maximum input loading , and maximum defection derived from that & rotational forces .
The barreled rollers let it run free while its doing it. the ball races ( particularly the deep groove ) restrain the deflecton .
This exceeds the side load capeability of the standard ball races . eventually .
The deep groove doesnt have that problem. Something else does .
We could call it a ' load flow path ' .
Tensile properties of the alloy cases , at high frequency ( 7.000 cycles ) are unlikely to match those in deflection , Static .
Then theres ' pre cambering ' the crank , to keep it nearer straight while at maximum deflection / strain .
. Id thought 2 1/2 , 5 & maybe 8 . :? 
