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Model specific boards => Golf mk2 => Topic started by: JezGTI on 11 December 2003, 16:10

Title: Tyres sizes and road speed
Post by: JezGTI on 11 December 2003, 16:10

I want to change my steel rims (original VW 14" (I think)) for BBS RA 15".  If I fit the wrong size tyres to the BBS wheels (which compared to my existing wheels / tyres would then have a smaller or bigger diametre) I assume that my speedo reading will be thrown out?  Does anyone know what tyres I should fit in order to keep my speedo accurate?

Title: Re:Tyres sizes and road speed
Post by: Blue MK2 on 11 December 2003, 16:13

i recently changed my tires for lower profile ones. it hasnt changed the speedo rating.

Title: Re:Tyres sizes and road speed
Post by: Golfgal on 11 December 2003, 16:22

yes it will, Thought 15 was standard tho  ??? I'm prb wrong.

You wanna talk to adam he's gone from 17 to 14 so u can imagen wat his speedo is doing lol

Title: Re:Tyres sizes and road speed
Post by: JezGTI on 11 December 2003, 16:24

That doesn't make sense, it has to make a difference?

Title: Re:Tyres sizes and road speed
Post by: Golfgal on 11 December 2003, 16:27

 ??? I said it will make a diff....

Am I bein silly again - I know wat I mean lol

Title: Re:Tyres sizes and road speed
Post by: JezGTI on 11 December 2003, 16:28

Comment not to you GG, to Blue.

Title: Re:Tyres sizes and road speed
Post by: Golfgal on 11 December 2003, 16:30

yay!! Did I get something right for a change?

Title: Re:Tyres sizes and road speed
Post by: Rob on 11 December 2003, 16:42

last year i had some print out give to me on tecnical spec's for 1990 gti's
standard wheel and tyre size i think was:-
8v  165/60 hr 14
16v 185/60 vr 14 i think.

Title: Re:Tyres sizes and road speed
Post by: Gambit on 11 December 2003, 16:52

work it out for both

a 15" wheel will run a 195/50 tyre

so its 15inches (381mm) + (50% of 195mm)

a 14" runs 185/60 tyre

so its 14inches (355.6 mm) + (60% of 185mm)

so overall diameter

for 14 is 466.6mm
for 15 is 478.5mm

making a difference of 11.9mm

which is negligible difference on the speedo

Title: Re:Tyres sizes and road speed
Post by: Gozza on 11 December 2003, 17:14

lol at carol vordeman (Gambit).

Good work, felt like I was sitting a maths exam there for a sec  :o ;D

Title: Re:Tyres sizes and road speed
Post by: Alexg40 on 11 December 2003, 17:23

Try this:

http://www.tyresave.co.uk/tyresize.html

Title: Re:Tyres sizes and road speed
Post by: JezGTI on 11 December 2003, 23:33

Cheers guys (and gals), appreciate the help.  The tyresave link is really handy, nice one Alex.

Title: Re:Tyres sizes and road speed
Post by: Dizzie on 12 December 2003, 00:52

205/40/17s are the same as 185/65/14s ;D sweet
hurry up loan so I can get some