fag layshaft ball bearing

going thru the box of gearbox parts i got w/ my '74 project i came accross a new fag 6203.c3 ball bearing, 8 balls, brass retainer, swiss made. i see that hemmings layshaft bearing is a 6203tb. fag site says c3 is radially clearnace designation and no data on tb altho t is textile impregnated retainer. anybody have any knowledge of the c3 designation and if it's suitable for the layshaft application? thanx, rick

From what I have gleaned about bearings, C3 gives more clearance than the others, none, C1, C2, C3. In other words it will tolerate more swelling with temperature. I haven't a clue if it is good for the layshaft bearing though. That's not much help.

Dave
69S

C2, C3, C4 and C5 are internal clearance designations, basically it is the space between the ball and the races, a 'normal' bearing fits between C2 and C3. The larger clearance bearings are a little bit more tolerant of shaft deflection and other alignment/tolerance changes (thermal expansion etc). All other things being equal I would use C3 or C4 for most applications in an engine/gearbox.

As a side note I have seen a KX500 that broke a crank because it was put together with a standard bearings not C4s, as the crank flexed the bearing runs out of angular clearance and changes the loading conditions on the crank webs.

Hmmm.… just noticed by accident that BMW uses the c3 in it's box. Must be ok but since I've already got the roller bearing I'll use it. Thanx for the replies