tyre sizes

[hanns gruber]

hi i need to get new tyres for the front on my E430.

at present there are 235's on the front.

can i stretch a 225 on it? i used to do it on my other cars so should be ok maybe?

there AMG wheels

 

[john925]

hi i need to get new tyres for the front on my E430.

at present there are 235's on the front.

can i stretch a 225 on it? i used to do it on my other cars so should be ok maybe?

there AMG wheels

I would be concerned if the tyres arent the right size for the rims In the event of an accident its a great excuse for your insurers to void your cover.

 

[hanns gruber]

i've ordered the tires, it wont effect road grip anyway having a reduced size. i used to have a 200sx and skyline and both had stretched tires. IMO it looks better.

sometimes you get the awful overhang on tires it doesnt make the rims look good.

 

[steve333]

+1 for what john posted,i would contact your insurance company & inform them to avoid potential problems in the future.

 

[grober]

First thing is you haven't said what rim width you have ? As others have said there might be insurance implications-- check the speed and load rating of your new tyres also. Tyres are such an important factor in car safety and handling - they are after all the only link between car and road. Check in your owner's handbook for MB's official tyre size/s [ probably staggered FRONT to REAR on an AMG model??] and stick to them would be my advice.

 

[Martyn_n]

i've ordered the tires, it wont effect road grip anyway having a reduced size. i used to have a 200sx and skyline and both had stretched tires. IMO it looks better.

sometimes you get the awful overhang on tires it doesnt make the rims look good.

As you've ordered them why now ask if they will fit? I have to agree that they may look better than overhanging sidewalls but I for one would not compromise safety for aesthetics.

 

[LTD]

Won't stretched tyres have differing load characteristics in comparison to having the same tyre fitted to the appropriate rim ?

 

[john925]

i've ordered the tires, it wont effect road grip anyway having a reduced size. i used to have a 200sx and skyline and both had stretched tires. IMO it looks better.

sometimes you get the awful overhang on tires it doesnt make the rims look good.

That slight overhang is very useful to stop you kerbing your rims. Tyres are cheaper to replace than expensive alloys if you have a mishap. All rim widths have a tyre width tolerance But its best to stick to MB specs. They dont do it for fun. I am going to change my rears soon. Thye have 225's and should be 245's I regret not making the dealer put the original 17 inch wheels back on instead of the 18 inch ones. They are all the same size with 225 tyres. All the rims are 8 inch and 225 isnt in my opinion wide enough for 8 inch rims

 

[renault12ts]

Do not worry, putting a 225 tyre on a 7.5 inch or 8 inch wheel is not a stretch.

If you had not said "stretch" then this would have been a sensible conversation.

Your 430 will have either 7.5 or 8 inch wheels. The standard tyres are 235.

My wheels are 7.5 inch and have (standard) 215 tyres on...if yours are a stretch, then mine are worse.

You don't say what profile the 225s will be.

So long as the tread is wider than the wheel you have no problem. 225 = 9inches.

 

[LTD]

All the rims are 8 inch and 225 isnt in my opinion wide enough for 8 inch rims

I'd agree with that.

My 8" rims at the front are 245
My 8.5" at the rear are slighty oversized at 275 (265 spec'd)

 

[renault12ts]

Guys lets not just speculate...if you know you are right then post...but if its merely an opinion then ...

 

[renault12ts]

That slight overhang is very useful to stop you kerbing your rims. Tyres are cheaper to replace than expensive alloys if you have a mishap. All rim widths have a tyre width tolerance But its best to stick to MB specs. They dont do it for fun. I am going to change my rears soon. Thye have 225's and should be 245's I regret not making the dealer put the original 17 inch wheels back on instead of the 18 inch ones. They are all the same size with 225 tyres. All the rims are 8 inch and 225 isnt in my opinion wide enough for 8 inch rims

If a 7.5 inch wheel can take a 8.5 inch tyre, then an 8 inch wheel can take a 9 inch tyre.

As for tolerance, the 225s are well within tolerance for either a 7.5 or 8 inch wheel.

The answer to the question should have more to do with the profile than the actual width.

See here:

http://www.alloywheelsdirect.net/information/fitting_chart/mercedes-benz

One of the tyre choices for a W124 was a 225 on an 8 inch wheel...and these guys know.

 

[john925]

If a 7.5 inch wheel can take a 8.5 inch tyre, then an 8 inch wheel can take a 9 inch tyre.

As for tolerance, the 225s are well within tolerance for either a 7.5 or 8 inch wheel.

I dont like the look on mine to be honest. Even the wall rubbing strip doesnt project beyond the rim. I think the 225 would be fine on a 7.5 rim. I wont be happy with mine until I can run to the cost of two 8.5 rims and 245 tyres for the rear and two 7.5 rims for the front. Just a lot of expense that I can do without just now

I am confused now. Just followed your link and they dont show an 8 x 18 rim. Have I missread the marks on my rims I wonder. I must admit it wasnt that obvious

 

[hanns gruber]

As you've ordered them why now ask if they will fit? I have to agree that they may look better than overhanging sidewalls but I for one would not compromise safety for aesthetics.

Because i posted THEN i ordered so i didnt order these before i posted

Won't stretched tyres have differing load characteristics in comparison to having the same tyre fitted to the appropriate rim ?

even the guy who fitted them said they will actually wear better as the tread is slightly flatter to the road.

Do not worry, putting a 225 tyre on a 7.5 inch or 8 inch wheel is not a stretch.

If you had not said "stretch" then this would have been a sensible conversation.

Your 430 will have either 7.5 or 8 inch wheels. The standard tyres are 235.

My wheels are 7.5 inch and have (standard) 215 tyres on...if yours are a stretch, then mine are worse.

You don't say what profile the 225s will be.

So long as the tread is wider than the wheel you have no problem. 225 = 9inches.

agreed this has been blown way out of poportion! on y skyline i had 10j rears with a 245 stretch with no issues. maybe next time i'll word it different. all dont and dusted now anyway and IMO look better for it. only thing is i want wider wheels now as i think the front are only 7.5j-8j which are too thin. also the rears i want bigger too. any suggestions?

 

[effbee584]

They are there, 8x18 is also shown for other models. I recently had to replace two 245/45/17's, damaged by local speed humps, a bit surprised at the cost (£163 each!) Will need two more at end of summer, considered 225/45/17's to save £30/£40 per tyre but see that the wheels are 8inch wide and the chart tells me they have to be 245's so that is what they'll be. Saving not worth the risk of an insurance assessor denying a claim.

 

[hanns gruber]

225 on a 245 is slightly different from 235 to 225. amg fronts can have 225 or 235 its no problem. alot of people seem to bang on about insurance claims????? are people planning to crash or something? as long as the tread is on the ground and is apt for the wheel then there is no problem IMO

 

[tobyone]

Interesting thread...
I used to sell wheels and tyres to the modified VW scene, so have seen just about every variation of tyre 'stretching (195/40 on 9"x16 etc!). It became/is a huge must have scene fashion, as it allowed much much wider wheels to fit inside the curvature of a given wheel arch, the side wall sloping inward to a narrower than normal tread, allowing a lower suspension set up etc etc...

'Mild' undersizing is ok, with some sidewall flex and adequate speed/load rating.

Generally, 225 section tyres are fine on an 8" rim, on many cars its the ideal on upgrading from smaller rims, dependant on profile. You will lose some comfort, grip and get a bit of harshness.
As for matching rears to downsize to match up with downsized fronts,, it may be useful to check a tyre size chart where you can compare circumferance and diameter, so speedo is within limits and diameter stays at least the same as the fronts! Here's A simple one CLICKY

For me, downsizing or stretched tyres isa step back in performance, just my opinion, but each to their own within reason. In Germany it's considered more mainstream to slightly stretch tyres, has been for many many years.

 

[Jimbonic]

To chuck in my tuppeny's worth, I have the same wheels on my E430 and have 225s (30 or 35 profile, IIRC) and have no problems. I get understeer, but am not sure whether that is due to in-built suspension / steering dynamics - people prefer to see where they're going to crash - or the slightly narrower tyres.

I'm going to go for the more standard 235 fitment when I change. 1) to see if it cures the understeer and 2) to reduce kerbing damage to the wheels (neither I nor my wife can park!!).