My mailer spat this back at me, so I am reposting this:
> ...
> My mechanic says that my wheels use ball bearings and not roller
> bearings.
Most (if not all) Midgets came with ball-bearing bearings in the
front wheels hubs.
>... some of the catalogs I've looked in ... appear to
>have sealed type roller bearings.
Roller bearings (needle roller bearings) are better as they
last longer (larger contact area to spread the load over.
I have just helped a friend put roller bearings into a 1275 Midget.
It was slightly complicated, as the new roller bearings changed
the offset of the hub relative to the stub axle, by about 2 millimetres.
This means that the wheel is 2 millimetres further away from the engine.
This doesn't sound like much, but meant that we had to make some spacers
for the disk rotor, and the locking split pin for the front wheel stub
castelated nut didn't quite fit. (hmm, bet I didn't spell castelated
properly).
The differences are small, but these gotchas do exist (depends on the
roller bearing you buy, this was what one supplier sold him).
If you buy from a reputable supplier, and explicitly ask for all the
bits needed to convert from ball-beraings to roller bearings you should
be fine. Your mechanic can take care of this for you, and the work
is all very straight forward.
Note that wear on the hubs may have occured to such an extent that the
bearings are "sloppy" - your mechanic will inform you if this is the case,
and regardless of what bearings you get, it should be fixed (or, if the
tolerances are close, you can use a gap-filling metal glue - your mechanic
will know about these - locktight et. al.).
>I am under the impression that the bearings currently in
>my front end are ball bearing type, similar in nature to those
>in a bicycle (not encased or sealed).
correct.
Ball bearings have a very small surface area to transfer the weight of
the car from the axle to the wheel. (needle) roller bearings provide
a much larger surface (so they wear better, last longer, etc).
--
John Barlow, Parallel Computing Research Facility, I-Block,
Australian National University, Canberra, 0200, Australia.
email = John.Barlow@anu.edu.au
[International = +61 6, Australia = 06] [Phone = 2492930, Fax = 2490747]
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