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Tyres and wheels
Posted: 08 Dec 2005, 21:38
by dajwid
Hi a couple of questions.
What are the standard size of wheels and tyres fitted to a 1981 westfalia?
I have tyres with (185 R14 C 102) written on them. 'as you see I am not a mechanic'.
I need a new set of tyres but I wouls like to fit the right size. i am asking as my speedo is wrong. It reads about 80kmh when I am only doing 65.
OK great because the van seems faster but!!
I also don't know what the weels are that are fitted to the van. any ideas?
Are they original ?
Thanks for any help at all
Re: Tyres and wheels
Posted: 08 Dec 2005, 21:58
by kevtherev
80kmh when I am only doing 65
....65? furlongs ,fathoms, miles, kilometers,P.H.? how did you find this "true" speed out
Posted: 08 Dec 2005, 22:11
by dajwid
followed the wife in our alfa romeo. (I know the speedo in the alfa is OK as it agreed with the speed camera)
Near my house is a speed warning camera (WARNING ! you are driving ......KMph over the limit) I am always under the limit . but clock says i'm well over.
I am pretty sure it is wrong.
Posted: 08 Dec 2005, 22:17
by protexblue
185R14C are standard issue.
Posted: 08 Dec 2005, 22:19
by R0B
im sure they are carat wheels.they are 14"wheels so i doubt its those that are putting your speedo that far out.you could do with a sat nav.that would give you an idea of your true speed
Posted: 09 Dec 2005, 06:06
by dajwid
Are there bigger tyres I could put on the rear wheels?
Posted: 09 Dec 2005, 07:45
by Cruz
Bottom of the page is a calculator, the top is set to standard wheels
http://194.242.159.246/brickyard/info/a ... ltwhls.htm
Speedo
Posted: 09 Dec 2005, 08:02
by cumbriankeith
Note -the speedo runs off the front left wheel so changing only the rears will not do it - perhaps you meant you would change them all...
Posted: 09 Dec 2005, 08:30
by Diamond Hell
By the sounds of it you need to change the speedo, not the tyres!
VW speedos are generally very accurate.
Posted: 09 Dec 2005, 16:38
by dajwid
Sorry my fault I'm trying to ask 2 questions at once. now I know the wheels are origional size I realise the speedo is at fault.
I will sort it out in the summer when I move back to the UK and need to change to MPH speedo.
The bigger tyres question was to try to squeeze a little more speed out of the bus. I know it won't be a lot but with only 50HP every little helps. that is why I asked abot rears. i need to change the tryres as winter is here tons of snow and I have slicks on the bus.
Posted: 09 Dec 2005, 17:58
by R0B
imo no matter what tyres you put on your 14"wheels.you wont notice any difference in speed...
Posted: 09 Dec 2005, 18:00
by Anonymous
You'll find that most speedo's over-read... even VW speedo's.
Yes you can go up in overall diameter for the rear wheels only, you don't have to swap the fronts.
You could fit 205/80/14 which is about 3cm taller overall. This would give you approx 5mph higher at 4,000 rpm in top gear... give or take.
It doesn't sound much but it all helps.
MG
Posted: 09 Dec 2005, 18:15
by matt
VW speedos are generally very accurate
not on transporters
our syncro on 15" is spot on by 2 diff gps systems
the camper on standard 14" is doing 55 when reading 60..
however, yours does sound way out
Posted: 09 Dec 2005, 18:26
by Cruz
Most speedo's are 10% out give or take aren't they?
That's why the jobsworths in blue USED to give people 10% leeway when jumping out from behind a bush (as a major heist takes place behind them)

Posted: 09 Dec 2005, 18:30
by Anonymous
Yup,
No two cable speedo's read the same and yes they are usually atleast 10% out.
You can usually make them more accurate by upping the overall diameter of the wheel and tyre combo. That said, mine now reads 5mph under as I've fitted 215/75/15's!!
MG