Norris and Andrew have it right on.
Just a few comments in addition to their accurate notes.
The shellac held over into the alloy rims and indeed the edges were sharp
and the corks gave extra support.
Often we've seen the valve hole circles on tires from corkless rims.
Many of the guys used to tear off the base tape to lighten the tire.
The old silk tires would stretch into the holes, and friction could cut the
stitching.
Motor pace tires were MADE Without base tapes.
It was imperative to have an absolute thick shellac base and the stitching
would be fixed in position by the shellac with no movement at all!
This assured best adhesion at high speed especially with the "bandage" on
the outside over sidewall casing and rim for maximum security.
Indeed the corks would protect the spokes from glue and when s spoke broke,
rarely a nipple, it was easier to unscrew spoke and replace with the cork
protecting everything.
Even with the double ferruled rims, one had to put enough glue on the rim to
have a uniform glue coating the bed so that the tire would be nice and
secure.
We always stuck a piece of tape or paper opposite the valve between the two
spoke holes around the seam so that in case of a
problem, one could get a start on tire removal when one had stiff fingers
and was in a hurry to rip the tire off the rim.
Corks were the REAL pro way to do things, but with the coming of new glues
and tougher tires, many of the older ways were discontinued.
Ted Ernst
Palos Verdes Estates
CA USA
> Ted Ernst will straighten us out on this I bet. A few issues: using
> shellac is different than rubber based rim cement, it runs more for one
> thing; early alloy rims had no eyelets; wood rims provided lots of surface
> and the corks make a metal rim more like wood in terms of tire adhesion
> and suitability for shellac. I nominate Ted for an answer because a) he
> was there, b) he knows all and c) a stayer (motor pacer) who didn't know
> how to keep a tire on a rim would not have lasted to this point.
>
> Joe Bender-Zanoni
> Great Notch, NJ
>
> Raymond Dobbins wrote:
>> Small corks designed to plug up the spoke holes on tubular rims. First
>> time I ever see these. They are both cute and cool ;)
>>
>> http://ebay.com/
>> Item number: 160091243688
>> What exactly is the purpose of these? The description says to prevent
>> glue from going into the spoke holes, but you don't really need the corks
>> to prevent that. You just apply the glue between the holes. And if you
>> were to get glue on the little corks...imagine what a pain it would be to
>> remove them from your tire when you pull it off the rim! You'd probably
>> end up with bits of cork all around your tire - Oh the horror, the
>> horror!
>> Ray Dobbins
>> Miami FL USA