kryten

My rear tyres are approaching the legal limit and with Dono coming up I've been looking at replacements.

Most of the questions I've seen about tyres have been about 205/45ZR17 tyres but on my RB5 WR PPP its got Potenza SO2 Pole Position 225/45 ZR17 (ESO2PZ) tyres - is that correct?!

The wheels themselves are Prodrive Speedline alloys - not sure how to tell if they're the originals, but they look the same as the other RB5 ones I've seen.

All the specs I've seen suggest 205/45 tyres and as I bought the car second hand this is the first set of tyres I've had to replace(the dealer replaced the worn fronts when I purchased it).

Don't 205/45 and 225/45 tyres have a different rolling radius? Would this affect speedo readings?

Is the handling likely to be improved/compromised if these tyres are not the standard size?

Just thought I'd check before I splash out on a new set!

The side edges of the rear tyres are a little worn (NOT the shoulders themselves) and I was wondering if this could be related to the 'rubbing noise' I've had from the rear (see

Andy Tang

iTrader: (3)

Those tyres would cause the rubbing noise!!!

Prodrive recommend 205/45 R17 tyres.

The closest tyre size is 215/40 R17.

I didn't have a problem with the 215/40 R17 Bridgestones on my Speedline wheels. The reason I got the rubbing noise was when I used the MIM's with an offset of ET45!!

I've removed the arch rubbers, and the rubbing no longer happens!

Are 225/45 R17 used all round on the car???

The rear tyres replace them with either of the sizes I mention, and there won't be a problem with rubbing.

If the fronts are the larger size, replace them with the correct size then!

Andy

kryten

Yes currently 225/45 on all four wheels.

I guess if I do replace the rears with 205/45 then it would cause some handling issues if I left the fronts on 225/45?

Silver Surfer

I have tried a whole variety of tyres. Put SO2's 215/40/17 and the car will be transformed. I found the Pirellis to be cr*p in the wet. Also no rubbing with this size

Sam H

I have heard that if you have different size tyres on a scooby it can ruin the transmission. I did this on my car and had to change to all the same size tyres.

Do 225 45 17 tyres rub on the wheel arches of your RB5?

I have prodrive 205 45 17 at the moment but would like to put a bigger tyre on.I wondered if you could put 225 40 17 tyres if they make this size on the car.

Sam

DavidLewis

Kryten,

Either:
1. Get Tyres of Northampton to supply your tyres for the 13th, arrive, wreck your existing tyres, then go home on a new set.

2. Fit new tyres whenever, but take the old ones with you to Donnington. Get ToN to switch them around for the price of a couple of drinks.

kryten

Looks like this is going to be an expensive discovery

225/40 seems to be a closer match to the Prodrive specified 205/45 (in terms of profile) than 215/40.

Are many people running 215/40?

What differences am I likely to notice in the ride when going to 215/40, compared to 225/45?

Any suggestions as to whether the ride will be a bit more harsh (due to lower profile) and whether the road noise may be reduced (due to less rubber on the road)?

The only other question really is whether I should fit these before Donington on the 13th, given I'll only get about 300 miles on them before then and whether there will be anything left of them after Donington!! (don't really want to trash a brand new set of tyres!!).

SteveB

iTrader: (1)

Kryten,

Do 1 or 2 above. Don't run your new tyres at Donno, they'll be worn out by the end of the day.

Prodrive only recommend 205/45/17 because they are tied in to Pirelli and they don't have a 215/40/17 in the P zero, plus, this size is closer to the cicumference of the original tyres.

I would have thought that with the 225 tyres, the handling would be worse due to over large tyres being fitted to the rims causing the side walls to not sit squarly(hope that makes sense), so, the tyres doesn't sit flat onto the road and more flex in the sidewalls.(only a theory)

I've got 215/40/17 S02 pp and am happy with with the ride and handling. Mine have now done about 300 miles and are still a bit squirmy when pushed, hence the suggestion to use the old tyres for Donno then bin 'em.

I've also found that by going to the 40 series tyres i've reduced the wear at which the outside edges have worn. A normal problem with which enthusiastically driven Scoobs suffer.

Steve.