Tyre Question

[Paul 60]

Fantastic! I have now ordered a set of Maxxis p185/80s. The only decision now is whether to leave the thin 25mm whitewall on the outside or the inside

To me this is a much better option than buggerising around with diff ratios on an original car and cheaper than going back to the cross plys. For my FB, I did (& do) like the idea of the cross plys but will only consider quality brand names like BF Goodrich. See the prices and 13" range for Coker Tyres (http://store.cokertire.com/13-inch-tire ... clear=true ) in the US. The US prices indicate how much some middle men in Australia are getting. If buying from the US, putting the tyres into a shipping container at a reasonable price is a very big challenge.

Does anyone want to buy some some cheap nearly new Haida 185/70s??

cheers

[MeFB]

That's a good result with the tyres

I went with the BF Goodrich in the radials, but can't help wondering if the bias ply would have been better because of the extra support through the tyre walls on the taller aspect ratio tyres

Could be a bit more research to be done here. Might be that bias ply is better for tall aspect ratio tyres and radial for low Time for some intensive Friday afternoon desk-bludging to find out

[Cal]

Got a bit of a point there, coz my Kumho tyres with 80 profile do seem like they have weak sidewalls. The sidewall is quite bumpy, and easy to press in with a finger.

Not sure if that's coz of the brand they are, or because of the taller aspect ratio.

With the supply of US sourced tyres, I understand the Aussie suppliers needs to make a profit and all that, but the prices for these tyres here when compared to US prices is nothing short of obscene.

[Paul 60]

Hi Mefb

These are my rough (and dubious ) calcs:

The bias tyres have a diameter of about 25.25" (radius 12.62"). The circumferance would then be 3.1416 x 2 x 12.62 = 79.29"

The 185/80s have a Diameter of 24.7" (radius 12.35"). Circumference would then be 3.1416 x 2 x 12.35 = 77.59"

79.29/77.59 = 1.022

threrefore the 80 series tyres will only cause a 2.2% speedo over read .... (if an under read) enough to get a ticket in Vic

Anyway the 70s I currently run have a diameter of about 23.2" (radius 11.6") Circumference is then 3.1416 x 2 x 11.6 = 72.89"

79.29/72.89 = 1.089 leading to an 8.9 % speedo over read.

cheers

[MeFB]

Yeah, that really does make a big difference to the speedo reading doesn't it When you look at the difference that the small increase in diameter make to the circumference it's a bit of a surprise.

I'm not sure how accurate a 50yo EK speedo would be though? Maybe I need to check? Did NASCO make a SATNAV

[Cal]

When I had 70 series tyres on mine, the speedo would show 50mph, but the sat nav showed 41mph.

When I put the 80's on, the speedo would show 50mph, and the sat nav showed 49mph. Much closer, though the accuracy of the speedo is debatable

[MeFB]

When I put the 80's on, the speedo would show 50mph, and the sat nav showed 49mph.

That's more accurate than the speedo in my late model Mitsubishi

Go the mighty Holden

[WayneXG95]

Some good info in here. Should this be a sticky?

[WayneXG95]

Just brought 5 tyres, Maxxis 185/80R13
Antique Tyres at Ingleburn quoted $700 but doesn't fit or balance, that's an extra $13.50 per tyre. Total $767.50.
Fishers Ghost Tyres Campbelltown quoted for the same tyres fitted and balanced at $720.

Not rocket science...

[Cal]

Wayne, don't the stock the Kumho tyres anymore in that size ?

They sure have gone up in price compared to when I bought them a couple of years back


Please tell me you're not going to do what others have done and put the whitewall on the inside?

[WayneXG95]

Now Pete. What dag would do that....

[adsman]

Hi All,

I have a similiar query and problem, just had my EK Ute over the pits to get licenced in WA and they have told me the tyres are to lower profile, the car is running 14 inch rims (HT i think) with 195 x 60 x 14's , what would be the correct profile to be running on 14 inch rims to keep the speedo legit cause im guessing that is the issue, not sure of diff ratios or anything, guessing its the original diff. Has brand new radials so im a bit reluctant to replace.

Cheers,
Ads

[Blacky]

God he must be a fussy bastard if he is knocking you back for that, .

[Devilrod]

I'd ask why he's knocking them back? What's he basing it on that they don't pass? Its not like they'd be fouling on the body or suspension.

[adsman]

As far a s I know the knock back actually came from the Main Roads, the mechanic didnt mention it when he gave me a list of repairs, wasnt until the paper work came back from the Main Roads that the issue arrised.