Ride quality trade off between 18's, 19's and 20's

[BBX5]

"The main problem on tracks and ruts is with the lower side-wall the rim is nearer to the ground and more prone to damage from the side of ruts and rocks etc in the road."

Lesser side walls are made stiffer and that transmits all of the road surface infirmities.

I had 18s on my stock car. They were great for comfort. Just switched to 19s with a 275/45 Michelin Latitude Sport. I have compromised some comfort for better handling and steering response. I have kept the 18s for the monsoon season when the raod conditions deteriorate considerably.

[grey]

Originally Posted by London Lad

The overall radius of 18 19 or 20 is the same so fuel economy is only effected by the wider tyre having more wind resistance and the increase in rolling resistance.

Frazer is correct in that the lower side-wall will transmit more bumps to the car and the wider tyre will cover more road area and 'find' more bumps.

The main problem on tracks and ruts is with the lower side-wall the rim is nearer to the ground and more prone to damage from the side of ruts and rocks etc in the road.

I went for 19s but I have to say if I was spec'ing the car again I would stick with 18s and save £900.

Thanks, You made some great points again.
In summary going to a 20" wheel (low profile wheels) could potentially cause more suspension damages than just to the wheel itself, and transmit more wear and tear to axels, CV joints, struts and eventually causing rattles in the cabin, especially on bad roads. Sydney roads are quite bad. I think you guys have convinced me to stick with my existing set of 19"s

BTW:
I made some calculations.
going from 19" 255/50 R19 to 20" [275/40 R20W and 315/35 R20W] you loose approximately 13% of sidewall height.

[grey]

Originally Posted by BBX5

"
Lesser side walls are made stiffer and that transmits all of the road surface infirmities.

I was assuming this and you have confirmed. Thanks.

[Fraser]

Originally Posted by grey

Is there a significant difference in harsh ride going from 19" to 20" ?

The ride quality difference going from 19s to 20s (or from 18s to 19s, 20s to 21s etc) is dependent on the road surface. On a perfectly smooth road there's no difference at all but the worse the road the more you'll feel the difference.
Unless you're a really keen on the look of the 20s, I stick with the 19s. You'll find also that 20s will be generally more expensive than 19s within any particular brand. If you do a search through the various threads on tyres you'll also find that people with larger diameter wheels and wider tyres complain more about uneven wear than those with smaller diameter wheels and narrower tyres.
I find it interesting that the BMW X3CCs than run in the Paris-Dakar – that are obviously designed to go very hard on all sorts of crap surfaces – run very narrow but tall tyres (235/85) on 16-inch rims.

[anzer]

I just took delivery of 2010 35d - I had an opportunity to go from 18's to 214 style 19's for $5k AUD swap price. Signed up for move from 18's to 19's whilst car was being delivered, but something in side me said that 1) the price seems rich 2) the look isnt that much better (in fact, in retrosepct I like the 18's style better now), 3) I can still put snow chains on if I want without issue 4) [THE MOST IMPORTANT ONE FOR ME ANYWAY] the ride quality where I live is just so much better - no bumps, smooth on rough roads etc. I slept on it overnight and rang the dealer the next day to say skip the 19's - leave stock please.

I'm really happy I stuck with my 18's. 19's and 20's do trade off ride quality - that's fact - its just a matter of what you want to put up with on a daily basis and what sort of roads you ride (e.g. if in Germany/US on freeway all day then 20's would be fine - if tracking tram tracks and avoidingn potholes in melbourne Australia then 20's would suck)

We rode 20's on test drive and my wife hated it, and it left me a bit embarrased trying to get her to like the X5 when it was giggling all over the place - not what you pay $130k AUD for ... when we then tried 35d with 18's it was like a different vehicle in real-world. All my opinion of course - each to their own.

[London Lad]

Originally Posted by anzer

I just took delivery of 2010 35d - I had an opportunity to go from 18's to 214 style 19's for $5k AUD swap price. Signed up for move from 18's to 19's whilst car was being delivered, but something in side me said that 1) the price seems rich 2) the look isnt that much better (in fact, in retrosepct I like the 18's style better now), 3) I can still put snow chains on if I want without issue 4) [THE MOST IMPORTANT ONE FOR ME ANYWAY] the ride quality where I live is just so much better - no bumps, smooth on rough roads etc. I slept on it overnight and rang the dealer the next day to say skip the 19's - leave stock please.

I'm really happy I stuck with my 18's. 19's and 20's do trade off ride quality - that's fact - its just a matter of what you want to put up with on a daily basis and what sort of roads you ride (e.g. if in Germany/US on freeway all day then 20's would be fine - if tracking tram tracks and avoidingn potholes in melbourne Australia then 20's would suck)

We rode 20's on test drive and my wife hated it, and it left me a bit embarrased trying to get her to like the X5 when it was giggling all over the place - not what you pay $130k AUD for ... when we then tried 35d with 18's it was like a different vehicle in real-world. All my opinion of course - each to their own.

Exactly what happened to me !

[Xenon]

I love the look of the 20's with the sport rims, but I find that it pulls alot when the road surface has small ruts in it from usual traffic. When I got my 07 I bought 19's off of a 09 so my winter tires would fit. The tires on the 20's are alot wider, especially the back, which is probably the big culprit for the pulling.

[HUK]

20s with 45 profile. Looks better, works better, odometer still too fast (0.5%).

And by the way, compared to my stock 19" RFTs, my 20s with 275s make for a MUCH more comfortable drive. So when you guys are discussing ride quality, don't forget to compare similar tires.

[Fraser]

Originally Posted by HUK

So when you guys are discussing ride quality, don't forget to compare similar tires.

I think that goes without saying. The discussion is just about the effect on ride quality of rim size and sidewall height. Assuming that you are trying to maintain the same rolling circumference, a bigger rim obviously equals less sidewall. If you throw in different brands, RFT or non-RFT, passenger or light truck construction etc, then, sure, you may get a different ride comfort result but the discussion then has the potential to sink to often meaningless anecdotal evidence.

[grey]

Originally Posted by Fraser

I think that goes without saying. The discussion is just about the effect on ride quality of rim size and sidewall height. Assuming that you are trying to maintain the same rolling circumference, a bigger rim obviously equals less sidewall. If you throw in different brands, RFT or non-RFT, passenger or light truck construction etc, then, sure, you may get a different ride comfort result but the discussion then has the potential to sink to often meaningless anecdotal evidence.

totaly agree.