From: marquis@netcom.com (Roger Marquis)
Subject: Re: Team Motorola will Race on Clinchers in 1993
Organization: Netcom 
Date: Sat, 9 Jan 1993 03:00:25 GMT

In article <3450013@hplred.HPL.HP.COM> jbrandt@hplred.HPL.HP.COM (Jobst Brandt) writes:
>Roger Marquis writes:
>
>This reminds me of an argument some biker started about bicycle
>wheels.  He based his "facts" on how many more wheels he had built
>than I and that "who should know better" what's going on in spoke
>failure.  I don't think Greg Lemond knows more about tire selection

A scientific investigation, with the proper methodology, and independent
validation would be nice.  Let me know if you have any such research
on hand. 

Hey Jobst, are you referring to my pointing out that I have built and
ridden many more wheels than you as support of my assertion that
straight guage spokes build stronger wheels than double butted spokes?

> [...] Lemond, who is often mentioned as a
>better than average descender rode locally with some of the guys to
>the coast going up Kings Mountain and down Tunitas Creek Rd.  After
>waiting at the top for the "slow" hosts, he promptly was off the
>back after the first turn.  

Using a single data point to support your assertion Jobst? ;-)  Believe
me, there is no way anyone on the peninsula could have dropped Greg 
unless he wasn't trying.  Perhaps he wanted to distance himself from
the riders you mention for safety reasons.

>Besides, I take this as a ploy.  You know very well how much and how
>far I ride just on my summer vacation both by my postings and from
>my nephew with whom you ride now and then.  I do not have to get
>into a pissing match here on who rides farther.

No pissing match intended but I do stand by my assertion that the more
miles you ride the more sensitive you are to things like tires.

What kind of weekly mileage have you been putting in lately anyhow?  
10 years ago I don't remember anyone, even Sterling and Keith, being 
able to get away from you on a dirt descent.  I also don't remember you
saying 'tires is tires' back then either.

>About tubular glue melting on descents:
>
>I have made measurements of this and know that aluminum rims get
>over 110 deg C descending in cold weather.  

I can only point out that long steep descents (like Marin Rd in
Berkeley or the backside of Mt. Hamilton are not a problem in regular
weather with Clement or Wolber glue.  When the ambient air temperature
gets above 95 or so I switch to Fast Tac and I haven't had a problem
(though would liked to have had clinchers available at a couple of
Davis criteriums and Colfax RRs.)  I do not know for rim temperatures 
but clearly, under all but extreme temperatures, modern sew-up glue does 
not have a problem with a broad range of standard rim operating
temperatures (unless you use Tubasti of course).

>About tubular glue giving rise to rolling resistance:
>
>  [...]   I got these from tests
>performed at the Japanese tire testing laboratories where clinchers
>and tubulars were tested.  The rolling resistance data has been made
>public and shows that tubulars, except for their constant glue
>losses, roll better than most clinchers.  The glue losses are
>constant and offset tubular performance curves so that they come in
>about the level of a Specialized Touring II.  
>
>jobst_brandt@hplabs.hp.com

Care to provide some of this data Jobst.  I'd like to see their
methodology.  BTW, have any of these 'tests' been independently
verified?

Roger Marquis (marquis@netcom.com)
Newsgroups: rec.bicycles.racing