May thinking too. Rolling resistance on the salt just can't be that bad.
John Beckett, LSR #79
----- Original Message -----
From: "Beth Butters" <bbutters@dmi.net>
To: "john robinson" <john@engr.wisc.edu>; <land-speed@autox.team.net>;
"'John Beckett'" <landspeedracer@email.msn.com>
Sent: Wednesday, January 26, 2000 12:16 PM
Subject: RE: concerning tires
> Just from a practical standpoint, we always bring a bicycle with
us to Bonnivile and it is the easiest rideing of anything I've ever ridden
on, that's got to mean something. kVACH
>
> ----------
> From: John Beckett[SMTP:landspeedracer@email.msn.com]
> Sent: Wednesday, January 26, 2000 6:39 AM
> To: john robinson; land-speed@autox.team.net
> Subject: Re: concerning tires
>
> John
>
> I believe the reason for shaving tires is to reduce the weight and
therefore
> the effects that centrifugal force would have on the tire at high speed
> (RPM).
> And half tread should work just fine.
>
> Rolling resistance is a whole other matter, but it can't be that much. My
> timeslips from Maxton and Bonneville would indicate that altitude, and
> slipery salt, are bigger factors than rolling resistance.
>
> John Beckett, LSR #79
>
> ----- Original Message -----
> From: "john robinson" <john@engr.wisc.edu>
> To: <land-speed@autox.team.net>
> Sent: Wednesday, January 26, 2000 9:09 AM
> Subject: concerning tires
>
>
> > Howdy,
> > A few of questions and observations:
> > I'm running "H" rated street radials on my H/CC at the Salt, they have
an
> > aggressive tread design, and one of the safety techs said that I should
> > shave the tread for better speed. Somewhere I read that the coefficient
of
> > friction of the Salt is on the order of cold wet asphalt, and my
feelings
> > were (when I purchased the tires) that the aggressive tread would help
in
> > traction. my speeds are 130-150, (150 hope full, anyway) Any thoughts
> here?
> > Also, I've been reading Forbes Aird 's book "Aerodynamics" published by
> > HPBooks1997, he has a very good section on tires and rolling resistance
at
> > the Salt, and it states in a passage relating to the Summers Brothers
> > Goldenrod that the tires soaked up 61% of the total drag at the record
> > speed, although the tire model used in the equation was based on 60 year
> > old data... are there any newer equations available? anybody know how to
> > test rolling resistance? or where I can get the info to do a rolling
> > resistance test?
> > Another book I just picked up and although it is directed at and about
the
> > solar vehicles built at various universities, is "The Leading Edge" by
> > Goro Tamai, published by Robert Bentley1999. This book is focused on low
> > speed aerodynamics and many of the concepts can be transferred to LSR.
> > Although it does have advanced math in it, with the limited algebra I
> > studied in high school, (well OK attended class and worried about
pimples,
> > girls and cars) I am able to follow most of it....probably because I
read
> > the Aird book first, easily understood math in it.
> > Two years or so ago, Motion Software (the Desktop Dyno people) were
> > developing a game/engine test software about Bonneville. It seems to
have
> > been in development, and then it died, anybody heard of it? got any
> insight
> > about why the program went away? they don't seem to answer their email,
> > although they are still in business. I'd like to get my hands on it,
just
> > to play with it.
> > anybody got any other reading material they'd like to share?
> > anyway, that's about it for now, drive careful
> >
> > John Robinson, Mechanician
> > Mechanical Engineering University of Wisconsin
> > 1513 University Ave.
> > Madison, Wi. 53706
> > 608-262-3606
> > FAX 608-265-2316
> > Current World Land Speed Record Holder
> > Bonneville Salt Flats
> > H/GCC 92 cu.in. 1980 Dodge Colt
> > 131.333 MPH set 1995
> > 136.666 MPH set 1996
> >
> >
>
>
>
>
>
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