From: jbrandt@hpl.hp.com (Jobst Brandt)
Newsgroups: rec.bicycles.tech
Subject: Re: Replacing a Silca floor pump gasket
Date: 14 Aug 2001 19:18:40 GMT

Andrew Muzi writes:

> With any pump, use a non-petroleum lubricant for the piston and
> seals.  Aside from the obvious problem of petroleum products
> damaging rubber and leather bits in the pump I think it's possible
> to shoot oil through the pump to your inner tube - another bad idea.

Another piece of bicycle mythology perpetuated.  Tire pumps and air
compressors have been lubricated with petroleum products (oil) for
ever and anon without damage to tires.  Yes, vacuum pumps have oil
traps but then they are interested in particles with volatility in
pressures of 10**-6 torr, not two or more atmospheres above ambient.
In all the years of riding tubulars with latex tubes, the only ones
that suffer from oil, I never saw a tube damaged by the oil from Silca
frame fit pump leathers.  I still have a lot of those tubes lying
around in plastic bags and they look good.  My floor pump works fine
on 10W motor oil and has done so for many years with no ill effect on
tubes.

Fear mongering about oil may be a method of selling more special
(expensive) bicycle oils.  It's like steel frames getting soft, tires
needing aging and all the other promotions we hear now about the need
for wearing goggles when bicycling.  As Lance says, he's an Oakley man
for life.  I believe everything.

Jobst Brandt    <jbrandt@hpl.hp.com>