Got Stretch?

Speedlaw · Post by **Speedlaw** » Tue Jan 20, 2004 8:23 pm

I don't really recall us having a discussion on this topic before, so here goes.

Has anyone found (either through experience, or through a guide somewhere) the limits to stretching a tyre?

I'm sure that 175-50 fits over a 7" wide wheel, which is actually pretty impressive, but are there limits to this? Are there cars out there that run even more stretched tyres?

As an example; would a 165-50 tyre safely fit on a 7" wide wheel?

Random 'Stretch on a Polo' pic:

Post by **Josh_PoloGTi** » Wed Jan 21, 2004 7:24 am

Over here, most tyre fitters will not stretch tyres.

Or if they do, they make you sign a document that states if your tyre pops off, explodes, etc etc, they are not held accountable.

polo2k · Post by **polo2k** » Wed Jan 21, 2004 8:25 am

i run 195/45/15 on a 7" rim and its a compfy streach i could prollyrun a 185 but i think 175 would be pushing it, not only for safty but also for inflation as the bead wouldnt seat easily

Speedlaw · Post by **Speedlaw** » Wed Jan 21, 2004 10:16 am

So you're telling me, that fitting a 165-50 tyre to a 7" wide rim is insane?

To be honest, I'm after some skinnier tyres for the front wheels. The only remotely identical tyres (radius wise) are 185-45-15, and 165-50-15. Both exist, but both are hard, if not impossible to get.

Project!

polo2k · Post by **polo2k** » Wed Jan 21, 2004 12:53 pm

i was going to tell you what 165mm in inches but i cant find my post with the conversion program in it (im sure i was in diy but i think josh has being tiding

)
if you work out what the mm is in inches and then id say not to have a tyre much narrower than 1" less (max1.5") than the rim
there was a pic on the vortex in the mk4 golf forum of mad srteach where it was s severe that the bead wasnt touching the rim and i class that as dangerous.

Speedlaw · Post by **Speedlaw** » Wed Jan 21, 2004 3:56 pm

Good point.

The wheel is 7" wide, which is 177,8 milimeters. The tyre would be 165mm, BUT - the inner bead of the tyre is even less wide...

Which would result in mad stretch yo.

Maybe I'll stick to 185-45 then.

polo2k · Post by **polo2k** » Thu Jan 22, 2004 9:35 am

couldnt find the pic i wanted but you should like this
speedy stop touching your self there only schmidts

pettsy · Post by **pettsy** » Thu Jan 22, 2004 3:02 pm

pics of the mk1 with these on were posted on cgti forum

http://www.kult-heart.de/Umb_02_Sons_B1b3_gr.htm

polo2k · Post by **polo2k** » Thu Jan 22, 2004 3:10 pm

the ones i saw on the tex were worse than that!!! :O

Speedlaw · Post by **Speedlaw** » Thu Jan 22, 2004 7:29 pm

polo2k wrote:speedy stop touching your self there only schmidts

Must... Have... Stretch!...

Speedlaw · Post by **Speedlaw** » Wed Jan 28, 2004 3:42 pm

Found some info. I took the 185-55 as a reference.

Spec | Sidewall | Radius | Diameter | Circumference | Revs/km | Difference

185/55-14 102mm 280mm 559mm 1756mm 569 0.0%

195/45-15 88mm 278mm 556mm 1748mm 572 -0.5%

185/45-15 83mm 274mm 548mm 1720mm 581 -2.1%

165/50-15 82mm 273mm 546mm 1715mm 583 -2.3%

165/45-15 74mm 265mm 530mm 1663mm 601 -5.3%

So the 165-50 will be fine. More or less.

Then I remembered this car:

Our Belgian friend Kristof here is running 175-50-13's on a 9 inch wide wheel. Nine. That's insane.

So that's all there is to it - unless someone can prove it's unsafe, I'm convinced the 165-50 will stretch over a measly 7 inch wide wheel. Wonder how it would look.