[HighlandPete]

Well I had to do it, had a wheel off an weighed the 160 style with Vredestein Wintrac on it. 21.9kgs.

Weighed on high quality digital bathroom scales (checked against two other weigh scales), all indicating the same, within about 0.1kgs.

Now I need to crunch a few other numbers, as I weighed the tyre at 9.7kgs before fiitting, and it was 9.7kgs... makes the 160 rim 12.2kgs. The 161 (8") front weighs 12.3kgs it appears.

I can see clearly why I can feel the difference and posted the following earlier in the thread, the rear 161 is 26.2kgs, compared to the current 21.9kgs. 4.3kgs. less unsprung weight each wheel on the rear.

Originally Posted by HighlandPete

I had the first chance to really try the winter tyres today at warmer temperatures (5 - 6 degrees) and no snow, or ice about. Now these weedy 17" wheels are same on all corners, and I have to say you can immediately tell the rear is benefiting from the lighter wheels and unsprung weight. The rear suspension works more smoothy, over the broken stuff...

Now what do these other wheel/tyre combinations really weigh?

HighlandPete

[doughboy]

Originally Posted by 335diesel

Weird that BM spend so much on R&D for "clean" engines then stick them in cars that weigh more than the moon.

That 1M weight is mildly insane.

A 335d Tourer (with m sport addenda) is 1720kg, so the 1M with a full tank of fuel and one passenger would weight more than a lightly fuelled derv load lugger!

[doughboy]

Pete - sounds about right!

On the wheel listings http://felgenkatalog.auto-treff.com/ they give the 161 as 9.7kg / 10.2kg for 8Jx17 and 8.5Jx17 resp.

The 160 is given as 12.0kg for 8Jx17.

[kaishang]

Originally Posted by 335diesel

Weird that BM spend so much on R&D for "clean" engines then stick them in cars that weigh more than the moon.

That 1M weight is mildly insane.

Mmm, BMW are ahead of almost everyone in fuel efficiency. You have to wonder how much further ahead they would be if all new BMWs weighed 200kg less.

[Em135eye]

I think Pete has just shown how dodgy some of the Felgen figures are. Look closely - they have some very random figures. Why on earth would a 161 weigh so much less than a 160? And Pete has shown they actually weigh more!

Pete - nice and light those Vreds!

DB - BMW site has pretty much all 3 series models within each shape group as weighing the same - which I'm rather dubious about.

Next mission - to find myself a weigh bridge!

Anyway, off to take the boy swimming in our middle aged but slightly lightish auto diesel estate

[HighlandPete]

Originally Posted by doughboy

Pete - sounds about right!

On the wheel listings http://felgenkatalog.auto-treff.com/ they give the 161 as 9.7kg / 10.2kg for 8Jx17 and 8.5Jx17 resp.

Felgen is way out for the 161. Using Falken data for the tyre weights, I make the 161 8", 12.3kgs and the 8.5", 14.8kgs. 10.2kgs is far too low, would make the tyre almost 16kgs.

HighlandPete

[doughboy]

Originally Posted by 335diesel

DB - BMW site has pretty much all 3 series models within each shape group as weighing the same - which I'm rather dubious about.

Almost every variant has a different weight given, right down to auto / manual versions of the same car.

E90
316d = 1400
318i = 1435
318d = 1505
325i = 1535
325d = 1600
330d = 1610
335d = 1655

The figures will be officially declared weight, so they must have some basis in proper traceable testing!

The 316d (with 2 litre engine) looks a good weight at 1400, how the 335d is 255kg more i don't know.

It must be more than engine / transmission weight. Stuff like exhausts, trim and sound proofing etc too.

[Em135eye]

DB - oops - I didn't check hard enough! I didn't know they still made a 316d either. I did notice the same weights for SE and M Sport though - if SE aren't lighter than M Sports then my name is Sheila.

255kgs IS a hell of a difference between models. How about base model petrol compared to the 335i?

Now I'm wondering how much the different engines weigh....

This could go on forever!

Felgen has a very high weights (nearly 14kg) for the 19" 313M - a "performance" rim that should be pretty light. Surely they are wrong?!

[HighlandPete]

Now here's a different aspect of running different wheels. We bang on about unsprung weight, but as we know, nothing is as simple as it first looks.

Good car design examines the relationship of unsprung weight to total weight, the "RATIO" of "Sprung to Unsprung Weight". In other words, the dynamics of the unsprung suspension will be far different, even if the same value, on a light car, when compared to a heavier car.

Apply that to our 3-series BMWs. A 318i petrol with a set of identical wheels to a 335i/d will ride and handle totally different. Purely on the sprung to unsprung weight ratio. Never mind the other aspects of weight differences.

So a 'lightish' model needs the wheel set to be as light as possible, or there is a disadvantage straight away.

Running with a loaded car often bears this out, the ride and handling, although different, often improves as the unsprung to sprung weight ratio increases.

So clear to see why, if we sample a few 3-series, they all seem to drive with different dynamics.

HighlandPete

[dxb335d]

Actually the saloon is lighter than the coupe!

[HighlandPete]

The guy I bought my 161's off, was replacing with Speedline rims. Around 7.8kgs each I understand, for 8" x 17". Those and non run-flats, I can see why he changed them after delivery mileage, his BMW would feel so much better in the suspension department.

HighlandPete

[F31-340i]

Originally Posted by HighlandPete

Well I had to do it, had a wheel off an weighed the 160 style with Vredestein Wintrac on it. 21.9kgs.

Weighed on high quality digital bathroom scales (checked against two other weigh scales), all indicating the same, within about 0.1kgs.

Now I need to crunch a few other numbers, as I weighed the tyre at 9.7kgs before fiitting, and it was 9.7kgs... makes the 160 rim 12.2kgs. The 161 (8") front weighs 12.3kgs it appears.

I can see clearly why I can feel the difference and posted the following earlier in the thread, the rear 161 is 26.2kgs, compared to the current 21.9kgs. 4.3kgs. less unsprung weight each wheel on the rear.



Now what do these other wheel/tyre combinations really weigh?

HighlandPete

LOL! Full marks for actually removing a wheel. What did your other half say?

17x8" wheel 12.2Kg, 19x9" wheel 12.9Kg - not much in it really.

[ALF_E90]

The staggered 18" style 162's with runflats (Michelin PS2 front, RE050 rear) that came on my car are in the garage so I weighed them just now when doing some weights. I used some fishing scales that I use for my mountain bikes, they are accurate to half a pound at least. The front was about 55 pounds (25kg) which shocked me - the rear was off the 56 pounds-max scale and you could not even extrapolate the scale as it was on the stop (past about where 60 pounds should be! That's pretty shocking, the wheels are allegedly only between 12 and 13kg each.

I have bought a cheap set of style 185 17x8 with well used non RFT on them from Ebay, when I collect them I will weigh a couple, and when I get the chance I will weigh one of the same with my Nokian WRG2 winter tyres on.

On another note, Highland Pete and others - how do you find Falken 452's? for 17x8 wheels I would always get full-premium summer tyres as they are so cheap. If I keep the 18's as well as my two sets of 185's (!) I may use 452's when the current tyres are worn but I have read mixed reviews, some people suggesting they have poor wet grip when they are part worn. Wet grip/braking/aquaplaning resistance are the most important areas of tyre performance and thje 255 rears are going to be markedly more prone to aquaplaning than 225's. Recent severe rain has seen me aquaplane all four tyres a few times around 60-70mph on major dual carriageways and relatively well-drained A roads, not in puddles just in surface water or runoff.

At the very least I may well run the 162's with the RFT this summer just to use them up - I'm fairly broke at the moment and don't particularly want to buy another set of tyres all round when the rears on the 162's are nearly new, and the fronts quite decent too. With the mileage I do they'll be gone by autumn. So I'll build up a good few miles on RFT to compare them with what comes next ( definitely not RFT, probably the 17's).

[F31-340i]

Originally Posted by ALF_E90

The staggered 18" style 162's with runflats (Michelin PS2 front, RE050 rear) that came on my car are in the garage so I weighed them just now when doing some weights. I used some fishing scales that I use for my mountain bikes, they are accurate to half a pound at least. The front was about 55 pounds (25kg) which shocked me - the rear was off the 56 pounds-max scale and you could not even extrapolate the scale as it was on the stop (past about where 60 pounds should be! That's pretty shocking, the wheels are allegedly only between 12 and 13kg each.

I have bought a cheap set of style 185 17x8 with well used non RFT on them from Ebay, when I collect them I will weigh a couple, and when I get the chance I will weigh one of the same with my Nokian WRG2 winter tyres on.

On another note, Highland Pete and others - how do you find Falken 452's? for 17x8 wheels I would always get full-premium summer tyres as they are so cheap. If I keep the 18's as well as my two sets of 185's (!) I may use 452's when the current tyres are worn but I have read mixed reviews, some people suggesting they have poor wet grip when they are part worn. Wet grip/braking/aquaplaning resistance are the most important areas of tyre performance and thje 255 rears are going to be markedly more prone to aquaplaning than 225's. Recent severe rain has seen me aquaplane all four tyres a few times around 60-70mph on major dual carriageways and relatively well-drained A roads, not in puddles just in surface water or runoff.

At the very least I may well run the 162's with the RFT this summer just to use them up - I'm fairly broke at the moment and don't particularly want to buy another set of tyres all round when the rears on the 162's are nearly new, and the fronts quite decent too. With the mileage I do they'll be gone by autumn. So I'll build up a good few miles on RFT to compare them with what comes next ( definitely not RFT, probably the 17's).

I ran my previous 330d on 17x8" wheels for over 60,000 miles with the following 225/45/R17 tyres:

1. Contis
2. Goodyear Eagle F1s
3. Falken 452s.

IMO the difference between them didn't justify not getting the cheapest (usually Falkens) - they were all good.

For me the grip benefits of 255s outweigh any downside - I'd stick with staggered set up - the tyres aren't really expensive in 18" sizes plus 162s look great.

The flashing yellow triangle of "no-grip" is far more common when I run 205 rather than 265 rubber at the back.

[ALF_E90]

Originally Posted by ///ajd

For me the grip benefits of 255s outweigh any downside - I'd stick with staggered set up - the tyres aren't really expensive in 18" sizes plus 162s look great.

The flashing yellow triangle of "no-grip" is far more common when I run 205 rather than 265 rubber at the back.

Well that's a vote of confidence for the Falkens. Premium 225/45/17 tyres are sub £110 though, which is a lot less than 255/30/18 rears (and of course it would mostly be rears you'd get through - I'd expect two sets of rears and one of fronts a year).

The ESP light does like to flash away more - and you can feel it braking the rear wheels even without flashing the light at times - with the 225/17's but that may be the softer winter tyres upsetting the ESP in my case. If I switch the DCT on or disable the system entirely there is plenty of grip there and a lovely balance, plus the sensational ride quality that made me want 17's all year round in the first place. I have not yet tried 18's with non-RFT so that would be worth a go, just to see.

I did think about putting 225/35/18's on the 8.5" rears but it didn't seem recommended and I'm wary for insurance reasons of going for non-standard sizes. This, the "front" size, must be a common size as it is way cheaper than 255. Staggered 17's seem expensive, as do the 130i sizes, they must be rarer.

[HighlandPete]

Originally Posted by ///ajd

LOL! Full marks for actually removing a wheel. What did your other half say?

You shouldn't ask. She just raises her eyebrows and shakes her head.

HighlandPete

[HighlandPete]

Originally Posted by ALF_E90

...On another note, Highland Pete and others - how do you find Falken 452's? for 17x8 wheels I would always get full-premium summer tyres as they are so cheap. If I keep the 18's as well as my two sets of 185's (!) I may use 452's when the current tyres are worn but I have read mixed reviews, some people suggesting they have poor wet grip when they are part worn.

I was running the Goodyear Eagle F1 GS-D3 before the Falken, selected as they were leading the pack for their wet performance. Being in the Highlands, the wet bias was key.

I was wanting to fit the F1 asymmetric, but the tyres were not available in 17" staggered OEM sizes.

Others were saying the Falken was good in the wet, and I found a test by "Wheels" where they had the Falken in the group with the F1 Asymmetric. Tests were on a 235/45 R17, so close call to our size. The Goodyear got first place, again good wet performance, the Falken came in second, again a good wet performer.

The tester stated:

Me? I’d opt for the new Goodyear Eagle F1 Asymmetric, despite its significant price premium. And, if it wasn’t yet available in my size, I’d be happy to drive off with the Falken FK 452 and pocket the change. This pair were up the sharp end of the field so predictably often, they’re an obvious choice if driving enjoyment really is your thing.

Your comment on part wear, I've read it as well. I've also read that it is likely due to the rubber compound work hardening due to heat cycles. More so than some other tyres So as I see it, if you really work them hard, they may tail off in performance.

Personally I'd like to try the ContiSportContact 3, as they are showing some top results in recent tests.

BTW, I found the Goodyear's did as expected, the Falken's are very similar in my conditions. I like them.

HighlandPete

[F31-340i]

Originally Posted by ALF_E90

Well that's a vote of confidence for the Falkens. Premium 225/45/17 tyres are sub £110 though, which is a lot less than 255/30/18 rears (and of course it would mostly be rears you'd get through - I'd expect two sets of rears and one of fronts a year).

The ESP light does like to flash away more - and you can feel it braking the rear wheels even without flashing the light at times - with the 225/17's but that may be the softer winter tyres upsetting the ESP in my case. If I switch the DCT on or disable the system entirely there is plenty of grip there and a lovely balance, plus the sensational ride quality that made me want 17's all year round in the first place. I have not yet tried 18's with non-RFT so that would be worth a go, just to see.

I did think about putting 225/35/18's on the 8.5" rears but it didn't seem recommended and I'm wary for insurance reasons of going for non-standard sizes. This, the "front" size, must be a common size as it is way cheaper than 255. Staggered 17's seem expensive, as do the 130i sizes, they must be rarer.

Quick look on Camskill:
for each 255/35/R18
Goodyear F1 £135
Falken452 £108
Avon ZZ3 £103
Enduro £63 (!!)

Goodyear F1 in 225/45/17 os £90-95, in 225/40/18 is £118.

Hence for Goodyear all round, staggered 18"s would be £130 more than same 17"s allround. The other way to look at it is that the rears would only be £70 more to renew each time.

This difference would obviously be a lot less on Falkens.

If money is an issue, I'd go for Falkens on the staggered 18"s everytime - you will feel quite a difference from the RFTs.

There will be less fundamental grip if you go for narrow 225 at the back. DTC etc. won't change the basics of this grip, only the extent to which the car tries to manage wheel slip with the grip available. DTC can improve overall traction for a given tyre size, but a 255 will always offer more basic grip.

It is also worth considering that if you find you are having to use/rely on DTC with 17" 225s at the back in order to improve traction, the DTC will be achieving that increased traction by allowing some slip. This may infact increase the wear on the 17"s to an extent that negates the original cost saving over 18"s.

[ALF_E90]

I realised after my post that on Camskill's prices there is less difference between 17's and 18's - on mytyres it was more like £50 each for the rears. If I keep the 18's I think, looking at Camskill's prices, I'd go for F1 Assymetrics - slightly off the pace in the latest tests but great in the wet, which is what I want.

No electronic system I have tried actually helps traction or speed through a corner for a remotely sensitive driver. A PSM-equipped Cayman S on track was impressive, but it still hindered ever so slightly by stopping the gentle slippage that results in optimum pace. They probably do protect your tyres though! 255 rears make the car more foolproof through increased traction but worsen the handling balance. Of course in the wet the narrower tyre probably has more outright grip. I'm glad cars come with advanced ESP systems and the BMW's is the best of any car I have owned, but I'm equally glad they can be switched off, I would have to think very hard about buying any car on which the system could not be fully disabled. I don't like big lairy slides or wheelspins, but I don't like systems hindering progress either.

I used Conti SC3's on the A4 last time around and it would not be going too far to say they transformed the drive - from the SC2's that were on before. Nice progressive but not excessive dry grip, great wet grip, great steering feel (the A4, like my electronic 330 setup, needed all the help it could get in that regard), and great ride. Refined too - important to me. They fell off badly in performance in the cold, but I think I just noticed that more last autumn as it went from warm to cold so quickly. Pricey though... and wore quite quick. But all my tyres do

[F31-340i]

Originally Posted by ALF_E90

No electronic system I have tried actually helps traction or speed through a corner for a remotely sensitive driver. A PSM-equipped Cayman S on track was impressive, but it still hindered ever so slightly by stopping the gentle slippage that results in optimum pace. They probably do protect your tyres though!

...I assumed when you said....

If I switch the DCT on or disable the system entirely there is plenty of grip there

...that you were using the DTC mode to help avoid the DSC cutting power and helping traction with some DTC managed wheel slip.

[Em135eye]

Another vote for non RFT Conti CSC3s. Utterly brilliant tyres.

[ALF_E90]

Originally Posted by ///ajd

...I assumed when you said....



...that you were using the DTC mode to help avoid the DSC cutting power and helping traction with some DTC managed wheel slip.

I am, I'm just making the point that just because the light is flashing a bit on the current 225 rears doesn't mean the car needs wider rears. With DTC on, nothing remotely worrying happens, no perceptible spin unless being an idiot - I get the feeling that either the standard ESP is far too sensitive, or it is not well calibrated for winter tyres and is mistaking some give in the tyre for slip. Sometimes (with the winter tyres) when I engage the cruise control on the motorway, say the cruise is set to 80 and my speed has dropped to 70, the ESP light flickers and the cruise disengages, even in the dry! That winds me up as you can't engage cruise control with DTC on.

With DTC engaged, I much much prefer the ride and handling and feedback with the 225/17's all round, hence this thread really. But I keep looking at the 162's in the garage and thinking that, for the warmer part of summer when I can actually see my car through the muck, I might well keep them as they do look nice. Luckily a few years of Caterham racing conditioned my wife to accepting piles of wheels/tyres in the garage - not that I actually have much time to fiddle with cars these days!