Date: Fri, 11 Oct 2002 02:07:41 +0100
Reply-To: Clive Smith <clive.harman-smith@NTLWORLD.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Clive Smith <clive.harman-smith@NTLWORLD.COM>
Subject: Re: Bigger Wheels and Unsprung Weight
Content-Type: text/plain; charset="iso-8859-1"
Thanks, I'll get on the case with mine.
Clive
----- Original Message -----
From: "George Thorburn" <thorgk@accesscomm.ca>
To: "Clive Smith" <clive.harman-smith@ntlworld.com>
Sent: Friday, October 11, 2002 12:40 AM
Subject: Re: Bigger Wheels and Unsprung Weight
> Clive
> I had a chance to weigh my stock spare tire and rim and the Audi 16 spoke
> rim I have.
> Stock rim c/w Dunlop SPLT5 load range D tire = 42.6 lb.
> the rim is marked 5 1/2J14 and D14x5.5 DIN DOT and has the VW/Audi
> trademark.
> The bare Audi rim (part # below) = 16.65 lb.
> These weights should be accurate. I weighed them on the scale at the
local
> Purolator depot. I will try and find a bare stock rim and send you that
> weight as well. I wonder why the weights James quoted for the South
African
> rims (see below) are so much more than the Audi rim? My guess is that
> these are shipping weights and include boxes and other packing materials.
> Thanks
> George
> '85 Westfalia
>
>
> ----- Original Message -----
> From: "Clive Smith" <clive.harman-smith@ntlworld.com>
> To: "George Thorburn" <thorgk@accesscomm.ca>
> Sent: Sunday, October 06, 2002 8:27 PM
> Subject: Re: Bigger Wheels and Unsprung Weight
>
>
> > Brill. I'd love to know what a standard rim weighs, do you know if the
14"
> > syncro rims are different than the 2WD? I think they are. Anyway, I will
> > weigh my complete wheel tyre setup as accurately as I can.
> >
> > Clive
> > ----- Original Message -----
> > From: "George Thorburn" <thorgk@accesscomm.ca>
> > To: "Clive Smith" <clive.harman-smith@ntlworld.com>
> > Sent: Monday, October 07, 2002 3:07 AM
> > Subject: Re: Bigger Wheels and Unsprung Weight
> >
> >
> > > Clive,
> > > The wheels I have are marked with the VW /Audi trade marks and the
part
> > #437
> > > 6010 25D (similar to yours) the size (6J x 15H2 ET45) is the same.
Mine
> > are
> > > not made by Ronal, I do not recognize the makers trade mark. I do not
> > have
> > > tires mounted yet but I am cocidering 215/65R15 or 205/65R15. If I
get
> a
> > > chance I will weigh one of the bare rims as well as my spare steel rim
> > with
> > > a new Dunlop 185R14 tire mounted.
> > > George
> > > '85 Westfalia
> > > ----- Original Message -----
> > > From: "Clive Smith" <clive.harman-smith@ntlworld.com>
> > > To: "George Thorburn" <thorgk@ACCESSCOMM.CA>
> > > Sent: Sunday, October 06, 2002 7:08 PM
> > > Subject: Re: Bigger Wheels and Unsprung Weight
> > >
> > >
> > > > I don't know about Audi 5000 wheels, I've got lovely 15" Audi wheels
> > > >
> > > > Code:
> > > > 6J x 15 ET45 VWAUDI LWF
> > > > 437 601 025 5625 072 Germany 8 89
> > > > (Audi 200 alloy wheels - same stud pattern as 5 stud Mercedes and
> > > > Volkswagen)
> > > > Tyres: KUMHO (Korea)
> > > > 195 R15 1005 Powerguard
> > > >
> > > > I'll weigh them soon, perhaps we can all weigh our spares and maybe
> then
> > > > we'll have some real data to work with.
> > > > If you pmail your results to me I'll collate them into a
spreadsheet,
> > Lbs
> > > or
> > > > Kgs no problem, just make sure you all pump them up to say 35 psi
and
> > > > calibrate your scales with a sack of potatoes first! :-)
> > > >
> > > > However, this will not determine any change to Moment of Inertia, if
> > > anyone
> > > > is interested in the effect on acceleration and braking distances.
> > > > I think we determined that 'worse case' their weight and moment of
> > inertia
> > > > might result in a 6-7% deficit (but I certainly haven't done any
> > > definitive
> > > > calculations). If we wanted to we could either a) Calculate MoI from
> 1st
> > > > principles (an horrendous task) b) Hang a known weight at a known
> > distance
> > > > from the centre (front 2WD, no drivetrain drag), trust that
everyones
> > > > bearings were in brilliant shape, no brake binding and use a
stopwatch
> > to
> > > > time the acceleration for the 1st 90 degrees of movement (and then
try
> > and
> > > > estimate a fiddle factor for bearing drag). The comparisons might be
> > half
> > > > valid but the absolute value would probably be wildly inaccurate.
> > > > Alternately, tyre balancing shop equipment might be used, to
> accelerate
> > > the
> > > > wheel and tyre to a know rotational speed, timing it accurately -
even
> > > then,
> > > > you'd have to know the electric motors torque curve to get any idea
of
> > > > absolute value for MoI. Lets forget it shall we, unless someone out
> > there
> > > > has a calibrated rig for just this purpose - I bet theres one within
> 40
> > > > miles of me, since nearly all Formula One and several World Rally
> > > > Championship cars are built within that compass of London (except
the
> > > > current F1 championship winning Ferrari!).
> > > >
> > > > Clive
> > > >
> > > > '88 Syncro Transporter
> > > > ----- Original Message -----
> > > > From: "George Thorburn" <thorgk@ACCESSCOMM.CA>
> > > > To: <vanagon@GERRY.VANAGON.COM>
> > > > Sent: Monday, October 07, 2002 12:33 AM
> > > > Subject: Bigger Wheels and Unsprung Weight
> > > >
> > > >
> > > > James,
> > > > The weight we need to know is the weight of the tire and wheel
> combined.
> > > If
> > > > the 15" wheel weighs more and the 15" tire weighs less then every
> thing
> > > may
> > > > be even. If the 15" tire weighs more than the 185R14 then the
> unsprung
> > > > weight would increase even more.
> > > > Has anybody checked this out. Also does anyone know how much the
Audi
> > > 5000
> > > > 15" wheel weighs?
> > > > Thanks,
> > > > George
> > > > '85 Westfalia
> > > >
> > > > >The popular Sunburst SA wheel is listed at 19lbs - only 1lb >more
> than
> > > > stock.
> > > > >But the Carat2 wheel, for example, is 23lbs...quick >math...that's
> 5lbs
> > > and
> > > > >28% heavier than the stock. And the Rhein style wheel is >24lbs!
> > > >
> > > >
> > > >
> > >
> > >
> >
> >
> >
>
>
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