right then i'm currently running 205 50 17's all round ,my fronts are going to be needing changing if i don't whip them onto the back soon.

the rears have 5 mm at least and want them up front asap.

i want to use 225 45 17 as they are cheaper.

is it advisable to use the two different profile tyres?if i wear out the fronts and replace them with the 225's and then do the rears as and when will this be ok ?or am i running a risk with handling and more importantly safety

basically i'd rather not bin perfectly good tyres (spare ncluded)just to save a few quid per corner.

is the rolling radius the same ?and will there be any detrimental effects if i go along with my plan,obviously tyres will be changed on the same axle.

but basically i can't affort 5 new tyres striaght off

Well they have the same rolling radius. Read recently on here that it would fail an MOT if the tyres were not all the same size tho.

Having said this, Ive don it on a previous car of mine, and 1 thing I found was in marginal grip conditions, the end of the car with the wider tyres had more grip! I put em on the front and got less understeer, but the back end was all over the place. (Pretty good fun really )

How does the price of 215/45's compare, have seen a few octy's with these on now out and about.

Basically as long as you stick to the same profile n the same axle I cant see why you would have a problem, as long as the rolling radius wasnt massively out, that may cause ABS related problems and the system will pick up wheel speed differences.

Read recently on here that it would fail an MOT if the tyres were not all the same size tho.

IIRC as long as the tyre sizes are the same on the same axle you are ok (eg got to be in pairs).

Well they have the same rolling radius. Read recently on here that it would fail an MOT if the tyres were not all the same size tho.

True.. they would normally.. but some of the more powerful RWD cars have bigger rear tyres?

True.. they would normally.. but some of the more powerful RWD cars have bigger rear tyres?

Thats what I thought at the time

A number of BMW's have different tyres sizes front and rear, if its OK for them . . .

I ran 205 fronts 225 back for at least 10,000 miles on my Octavia vRS, no problems. However, there are some threads which sugest it is incorrect or possibly illegal (or both) to run wider tyres at the front, as this affects handling :eek: .

Do a search on the threads ("205 225"), hope this helps .

Rich

I ran 205 fronts 225 back for at least 10' date='000 miles on my Octavia vRS, no problems. However, there are some threads which sugest it is incorrect or possibly illegal (or both) to run wider tyres at the front, as this affects handling :eek: .

Rich[/quote']

I had heard that too. IIRC you can run wider tyres on the back but not on the front and as long as the front 2 are the same and the rear 2 are the same there shouldn't be any problems with the law. On another note I have just swapped from 205/55/16 to 225/45/17 and the difference in grip is unbelievable, the car handles and feels so much better it's getting quite scary on the drive home through the twistys!

so good 205 17's to the front and new 225 45 17's to the rear should do me fine ,util i can change the fronts?

thanks for the input guys

so good 205 17's to the front and new 225 45 17's to the rear should do me fine ' date='util i can change the fronts?

thanks for the input guys[/quote']

Put the 225 on the rear and the 205 on the front until you can change. I did this myself and had no problems.

As for 215.....this will give a greater speedo error than the 225s.