Never buying low profile tyres again!

Owen

Just switched the 75 from it's 225/45/17's to a set of 215/55/17's. The wheels look much chunkier - so from an asthetics point of view they may not be trendy low profile tyres anymore, but they fill the arches nicely.

Main bonus? Comfort! Potholes no longer go up through me every time I hit one, and the car seems to be much more sure footed on the road. I'm even considering doing the same to the MINI - they seem much more suited to Irish roads.

gerrycollins

couple of years ago buying a new car wanted a particuclar set of alloys that were only available in 17inch however it would need me to get a very low profile tyre and the car salesman in fairness to him advised me against it saying it would not be a comfortable ride even on city streets never mind the country roads.

had a test drive in a car later that day with very low profile tryes and Jesus wept for my sore arse after a quick trip around liffey valley area with its speed bumps etc and I was only doin 5mph max over the speed bumps

peasant

55 IS low profile (mine sits on 82's)

Owen

peasant wrote: »

55 IS low profile (mine sits on 82's)

Yeah, but you're the type of motoring enthusiast who'll eventually end up in a Unimog

.Longshanks.

I recently went from 225/35/18's to 225/40/18's.

At the time of change over I kept a good eye on the speedo and the km's to work
- The rev's were the same when doing 120 kmph at roughly 3150
- The digital read out of the speed on the dash was still saying 116 kmph when the needle is pointing to 120 kmph with the cruise control is on
- I clocked the distance to work to the nearest 100m. No change over three runs measured

The upshot was that the cat-eyes on the road no longer felt like boulders! But 35% profile was probably too low in the first place

Shane732

PaintDoctor wrote: »

Just switched the 75 from it's 225/45/17's to a set of 215/55/17's. The wheels look much chunkier - so from an asthetics point of view they may not be trendy low profile tyres anymore, but they fill the arches nicely.

Main bonus? Comfort! Potholes no longer go up through me every time I hit one, and the car seems to be much more sure footed on the road. I'm even considering doing the same to the MINI - they seem much more suited to Irish roads.

Don't do it to the mini - please I beg you!!!

My ZT feels lovely on the 225 45 18s which should be on it compared to the 225 40 18s that were (wrongly) on it when I bought her. The 225 40s were fairly worn too though.

-Corkie-

I was only drove the missus`s 08 Passat up the country at the weekend and it has 245/45/17`s on. My god was it rough. Even hitting a cats eye when changing lanes was rough. My own passat has the poverty spec steel wheels so back ache with that...:)

vectra

225/45/17's on my vRS and no problem with bumps etc.

-Corkie-

vectra wrote: »

225/45/17's on my vRS and no problem with bumps etc.

Pictures?????..

vectra

-Corkie- wrote: »

Pictures?????..

:P

Couple of teasers here for you

-Corkie-

Very nice... The new plates will really make a differ. I hate those plastic ones... Your some man with a camera btw..

Owen

+1 on the niceness. That will be one to keep an eye out for. Loose the numberplate surrounds and dealer stickers though

996tt

only thing that bothers me about my low profiles is the cat eyes on some of the irish motorways, never seen anything like it in the rest of europe and there is no way of avoiding it. even the back roads dont bother me(used to alway travel athone to galway via moylough), just take my time on the bumpy sections

vectra

-Corkie- wrote: »

Very nice... The new plates will really make a differ. I hate those plastic ones... Your some man with a camera btw..

German plates to be ordered possibly this week with the hidden mount kit.;)
I could be a lot better with the camera...Must practice a bit more and do a proper photoshoot this week.

PaintDoctor wrote: »

+1 on the niceness. That will be one to keep an eye out for. Loose the numberplate surrounds and dealer stickers though

As above
Plates-Surrounds etc. to go shortly

ytareh

peasant wrote: »

55 IS low profile (mine sits on 82's)

Im open to correction but im guessing thats the speed/load rating-prob has a letter like H after it ,profiles are in multiples of 5 or 10.

*Kol*

I drove a car on 35% profile tyres recently. It was a nightmare scanning the road for the slightest pothole or defect.

Matt Simis

*Kol* wrote: »

I drove a car on 35% profile tyres recently. It was a nightmare scanning the road for the slightest pothole or defect.

As I always chip in on these threads.. xxx - 30 - xx and xxx -35 - xx are not always low profile if the tyres are wide. Cars like S8's have 20" Rims with 35% profiles but on 275 and 285 widths which give a sidewall height much taller than regular car wheels.

Also a good OEM suspension setup can be made from factory to use low profile without the major decrease in comfort thats being suggested. Then there are Alfa's that come with "mid" profile tyres that make you feel you have ultra low profiles on (again fault of the suspension)!

PaintDoctor

PaintDoctor wrote: »

Just switched the 75 from it's 225/45/17's to a set of 215/55/17's. .............. I'm even considering doing the same to the MINI - they seem much more suited to Irish roads.

Wouldn't do the same to the Mini, perhaps it's all the stuff you carry about makes the 75 nicer on the fatter tyres.

Wibbs

IMH the whole ultra low profile tyre is as much a fashion as anything else. It seemed to start with the whole touring car look 20 years ago. Smooth circuits, you then need bigger brakes to increase laptimes, that require bigger rims and they're a good idea. On road cars? With variable road surfaces and without the need for huge 6 pot calipers? Not so much. With a higher profile you can dial in different levels of sidewall flexibility without farting around with the suspension so much. Air and rubber is a good absorber of forces, metal isnt. The former is cheaper too. Look at F1 cars. They aint running "big rims" or anything like it. Rally cars will, again because of the need for humongous brakes.

I'd say spoilers and wings(and yes there's a diff) would be similar in many cases. Fashion is a lot of it. That and an inherently unstable basic design. Look at an early 60's lightweight racing E type. Not a wing or spoiler in sight and perfectly stable at very high racing speeds.

101sean

Low profile tyres have to be a huge mistake on our roads. I have the complete opposite on my two (typical LR owner on big tyres 255/85R16 and 9.00R16) and still rattle around badly on our potholed roads.

The excellent Honest John column in the Uk Daily Telegraph motoring section rightly preaches against the use of optional 17/18" rims for general use and the UK roads are much better than ours. As for the those who drive bling Range Rovers/ X5 pimpmobiles with rubber bands on 20-22" rims, words fail me :mad:

peasant

ytareh wrote: »

Im open to correction but im guessing thats the speed/load rating-prob has a letter like H after it ,profiles are in multiples of 5 or 10.

Nope ...the load rating is 104/106, no idea what the speed rating is without checking.

These are C-tyres size 195/14 (note, no 55 or 65 or whatever) which means they are "full/standard profile" which is generally said to be 82 (not written on tyre) or 80 (when written on tyre)

Wheelnut

ytareh wrote: »

Im open to correction but im guessing thats the speed/load rating-prob has a letter like H after it ,profiles are in multiples of 5 or 10.

Nope, it's the size. Older tyre sizes without a profile number were generally 82%.

Stephen

My yoke here has 255/35/ZR20 tyres. Roads here are pretty good - I'd hate to have them on Irish country roads. Can think of several nasty bumps on the way home that would probably damage them at any kind of high speed!

BeardyGit

vectra wrote: »

German plates to be ordered possibly this week with the hidden mount kit.;)

Maybe I'm missing something here, but why would you put german style plates on a czech car?

Gophur

kev_Longshanks100 wrote: »

I recently went from 225/35/18's to 225/40/18's.

At the time of change over I kept a good eye on the speedo and the km's to work
- The rev's were the same when doing 120 kmph at roughly 3150
- The digital read out of the speed on the dash was still saying 116 kmph when the needle is pointing to 120 kmph with the cruise control is on
- I clocked the distance to work to the nearest 100m. No change over three runs measured

The upshot was that the cat-eyes on the road no longer felt like boulders! But 35% profile was probably too low in the first place

You went from 615mm diameter to 637mm diameter, an increase of 3.58%

Given the speedo and oddometer are not going to change, how would you notice any change in the readings? The revs will still be the same for any indicated speed.

Your speedo is calibrated based on a given tyre/wheel size, of course you will change the gearing if you change any component.

http://www.tyresave.co.uk/tyresize.html

Gophur

Gophur wrote: »

Given the speedo and oddometer are not going to change, how would you notice any change in the readings? The revs will still be the same for any indicated speed.

Your speedo is calibrated based on a given tyre/wheel size, of course you will change the gearing if you change any component.

http://www.tyresave.co.uk/tyresize.html

If you change the gearing by having bigger or smaller wheels the revs/min of the engine would be different for indicated mph speeds compared to those prior to the change.

vectra

RoverCraft wrote: »

Maybe I'm missing something here, but why would you put german style plates on a czech car?

For 2 reasons

1) Technology in the Car being German

2) I like them

.Longshanks.

My point was that because the speedo is already delibertly over calibrated by the manufacture, the marginal increase I made by fitting slightly bugger tyres has probably brought my speedo back into line with the true reading

Gophur

RoverJames wrote: »

If you change the gearing by having bigger or smaller wheels the revs/min of the engine would be different for indicated mph speeds compared to those prior to the change.

Incorrect.

The speed measurement is made at the gearbox, not at the road. The ratios between the speed measurement and the engine will remain unchanged. While your indicated speed will not change, your actual speed will change.

Get a GPS speedometer.

peasant

kev_Longshanks100 wrote: »

slightly bugger tyres

fitted cheapo chinese ones, did ya? :D:D

.Longshanks.

peasant wrote: »

fitted cheapo chinese ones, did ya? :D:D

Yeah - feel off the back of a lorry too! ( stupid iPhone keyboard!)

I bloody wish- they are falkens 552 or something like that. That was 18 months ago and need another set soon

Gophur

Gophur wrote: »

Get a GPS speedometer.

And some different sized tyres ? No thanks I'll take your word for it.

positron

PaintDoctor wrote: »

Just switched the 75 from it's 225/45/17's to a set of 215/55/17's.

Quick question, also considering moving from 225/45/17s to something with a bit more rubber, and I see you have gone for 215 just wondering if 225/55/R17 was an option?

peasant

positron wrote: »

Quick question, also considering moving from 225/45/17s to something with a bit more rubber, and I see you have gone for 215 just wondering if 225/55/R17 was an option?

If you want to stay within or near the original diameter, once the flank gets higher (from 45 to 55) the width has to get narrower (ie. from 225 to 215) not remain the same or get wider.

Flank height is a percentage of width, not an absolute dimension

Damaged one of my 225/45-17's on a pothole on Saturday (in a bl**dy unfinshed housing estate) so went for my winter tyres a bit early. I agree with the OP, 215/55-16 (on a 9-5 Aero) suit Irish roads much better.

Looks like the 17's had gotten their fair bit of a beating over the years. 3 out of 4 rims had at least one flat bit on a lip.

pajo1981

RoverJames wrote: »

If you change the gearing by having bigger or smaller wheels the revs/min of the engine would be different for indicated mph speeds compared to those prior to the change.

No it won't man - the car only knows how fast the wheel is turning, nothing else.

*Kol*

Matt Simis wrote: »

As I always chip in on these threads.. xxx - 30 - xx and xxx -35 - xx are not always low profile if the tyres are wide. Cars like S8's have 20" Rims with 35% profiles but on 275 and 285 widths which give a sidewall height much taller than regular car wheels.

Also a good OEM suspension setup can be made from factory to use low profile without the major decrease in comfort thats being suggested. Then there are Alfa's that come with "mid" profile tyres that make you feel you have ultra low profiles on (again fault of the suspension)!

These were rubber bands around the wheel. Somebody pointed out to me that they thought one of the wheels were flat because the tyres were so small looking!!!

Matt Simis

*Kol* wrote: »

These were rubber bands around the wheel. Somebody pointed out to me that they thought one of the wheels were flat because the tyres were so small looking!!!

What exactly is "these" though?

knipex

245 x 45 x 18 on my car.

Rides well.

Only issue is the price of tyres........

Matt Simis

knipex wrote: »

245 x 45 x 18 on my car.

Rides well.

Only issue is the price of tyres........

Probably would. 265-40-18 (or 285-35) on my BMW rides (alot) more comfortably than 205-55-16 on my Alfa. People confuse crap suspension with tyre problems.

Tea 1000

Matt Simis wrote: »

Probably would. 265-40-18 (or 285-35) on my BMW rides (alot) more comfortably than 205-55-16 on my Alfa. People confuse crap suspension with tyre problems.

Very true. Audi were criticised recently by one of Autocar's better guys, in that he was saying that the A4 or even A6 don't ride well at low speeds over uneven surfaces, and it was made all the more annoying by the fact that the R8 coped better, proving that a bit of money thrown at the suspension really is the answer.

245

samih wrote: »

Damaged one of my 225/45-17's on a pothole on Saturday (in a bl**dy unfinshed housing estate) so went for my winter tyres a bit early. I agree with the OP, 215/55-16 (on a 9-5 Aero) suit Irish roads much better.

Looks like the 17's had gotten their fair bit of a beating over the years. 3 out of 4 rims had at least one flat bit on a lip.

Samih - who fitted your winter tyres and how much did they charge?

Inbox

Intresting as I have 245 35 19 front and 275 30 19 on the back of mine,ride is fine except for ridges in the road,how much a bigger profile could I go?

Wheelnut

Gophur wrote: »

The speed measurement is made at the gearbox...

A lot of the new models are taking their speed signal from the ABS sensors.