swapping wheels

[parrot of doom]

I have 16s on the back, 15s on the front, but the fronts are 60's (backs are 55's) which are too big as they rub on full lock sometimes.

Is there any problem with swapping the wheels from front to back? I don't fancy buying new front tyres just to eliminate a little bit of incovenience when parking....

[tvrbob]

Those profiles sound wrong. I'm sure mine were smaller than that.

[JR]

tvrbob said:

Those profiles sound wrong. I'm sure mine were smaller than that.

205/60/15 front and 225/55/16 rear were the original sizes.

[JR]

parrot of doom said:

I have 16s on the back, 15s on the front, but the fronts are 60's (backs are 55's) which are too big as they rub on full lock sometimes. Are there any problem with swapping the wheels from front to back?

Yes: different width, diameter, offset.

parrot of doom said:

I don't fancy buying new front tyres just to eliminate a little bit of incovenience when parking....

Well be more careful when parking, forkout, or sell the car?

[ads]

JR said:

tvrbob said: Those profiles sound wrong. I'm sure mine were smaller than that. 205/60/15 front and 225/55/16 rear were the original sizes.

Mine are 205/55/15 front and 225/50/16 rear, and they are the original sizes. Although I think the factory changed the tyre sizes at some time in 1995.

[chim666]

ads said:

JR said: tvrbob said: Those profiles sound wrong. I'm sure mine were smaller than that. 205/60/15 front and 225/55/16 rear were the original sizes. Mine are 205/55/15 front and 225/50/16 rear, and they are the original sizes. Although I think the factory changed the tyre sizes at some time in 1995.

Mine are 205/60/15 front & 225/50/16 rear...and mine rubs a bit in reverse.
Good fun, these cars, aren't they!

[The Surveyor]

POD

Just re-read your original post, are you suggestion swapping the wheels from the front to the back, as in running with 15's at the back and 16's at the front?

Now that would look interesting????

[M@H]

The Surveyor said:

Now that would look interesting????

Thats not the word I would use

[parrot of doom]

JR said:

Well be more careful when parking, forkout, or sell the car?

Thanks for that, I'll try and be a little more perfect in future. FYI I'm no cheapskate.

[Ribol]

Have I got this right, you are thinking of driving a 150mph sports car with 16" rims on the front and 15" rims on the back?

[chassis 33]

Don't POD, please dont, for a start the offset in the wheels is 7mm different, (you will notice the difference in handling, I promise). Also the rears are wider anyway by 1/2in at the rim so despite sitting further out at the hub, the rim prodrudes further inboard and outboard.

In short it wont work, sorry.

Regards
Iain

[2 Smokin Barrels]

The early Chimaeras rubbed the front wheel on the battery box on full lock. Perfectly normal!

[parrot of doom]

Thanks Chassis33, that was the answer I was looking for.

I'm just not into spending 200 notes on new front tyres just because they rub a tiny bit.

[chassis 33]

parrot of doom said:

Thanks Chassis33, that was the answer I was looking for. I'm just not into spending 200 notes on new front tyres just because they rub a tiny bit.

No worries.

Out of interest are they rubbing when the wheels are turned in both directions if full left and full right. It's not unheard of, certainly from my Tasmin experience, for the bodies to be very asymetric and also just dumped on the chassis, I know of S series that are well over 1 1/2" out, where the body was just bolted up where it landed. The front end of my Tasmin has about 6mm between the OS wheel and the front of the arch but more like 20mm on the NS. I noticed this early on in the restoration and checked the chassis was straight when it was stripped.

[/nerd mode]

Regards
Iain

[parrot of doom]

Offside rubs when driving forward, giving it large on a right hander. Nearside rubs against the battery box when on full lock in reverse.

[M@H]

chassis 33 said:

Don't POD, please dont, for a start the offset in the wheels is 7mm different, (you will notice the difference in handling, I promise). Also the rears are wider anyway by 1/2in at the rim so despite sitting further out at the hub, the rim prodrudes further inboard and outboard. In short it wont work, sorry. Regards Iain

The rim width is fairly academic though really as the tyre is wider than the rim A 225 on a 7" rim will rub just the same as a 225 on a 7.5" or 8" rim assuming the centre line is the same.

As for the offset though you're quite right, due to the larger offset the extra rim width is seen on the inside edge rather than outside. However IIRC the combination of extra offset and the wider wheel gives the same front space (within a mm or two) so doesn't protrude outboard any more than the 15" rim.

Cheers,
Matt

[chassis 33]

That's why I constantly refered to rim width, because thats the only known in the equation. The width of the mounted tyre will have slight variations due to the carcass width thats labeled, the manufacters design, how square the shoulder is, how many plys of reinforcement in the shoulder and the like, and the age of the mould it came out from.

As such a Toyo may rub, a Bridgestone may lightly rub on brand new rubber, but so lightly you dont notice it unless you look for the mud thats been removed, and Goodyears not rub at all. (These are all plucked out at random.)

The rolling diameter of a tyre is subtly different depending on the with of rim its mounted on. The narrower the rim, the more the carcass is squeezed onto the rim and the greater the diameter. So the rim width does affect to an extent the likellhood of rubbing.

Regards
Iain

[Ribol]

I can't believe nobody has mentioned the gearing/speedo reading side of things yet which would have been my first concern.

[M@H]

Ribol said:

I can't believe nobody has mentioned the gearing/speedo reading side of things yet which would have been my first concern.

..its only about 3% on the Rolling Rad

>> Edited by M@H on Monday 8th August 13:09

[tvrbob]

As they tyre choice goes wider the profile is reduced so that the overall diameter remains the same. No gearing issue.

As for different manufacturers having different tread widths. I've seen this between tyres from the same manufacturer. Bridgestone SO2's and SO2pp's have around 25mm difference in tread width.