Downsizing wheels for smoother ride

[Sepsi]

Dear MB owners,

First of all thank you for giving me access to these forums.
I have a thought in my head which is bothering me since I bought our car 2 months ago.
So we own a MB '63 plate B200 sport, 1.8 diesel 136bhp, automatic. The aspect of the car inside and out is insane. I got in love with it from the moment I first saw it. And it serves the purpose as a family car great, due to the raised position of the seats (there's no need to bend down anymore when putting the baby in his seat) and the pletny of space it offers.
The one thing which I am not entirely sold on are the wheels and the ride comfort they offer. The wheels it came with are: 225/40 R18 W. Although the aspect of them on the car is insane, they really make you feel every little ondulation and hole in the road. Sometimes it is that bad, that you get annoyed and frustrated, and definitely that is not something you should experience in a family car. I am not sure if anyone else is feeling or experienced the same, but that is my own view and I will take all the criticism it may attract.
The thing that went in my mind was to downsize the wheels and get tires with a higher wall so they can absorb some more disturbances from the road.
As I am not an expert and I have never done that I am not sure what that will imply afterwards.
I had in my mind to go for 215/45 R17 W, or 205/50 R17 W or even 205/55 R16 W.
Do you guys think the car will feel immediately better after downsizing? How much beeter it will feel? Will it be a dramatic increase in comfort or just a marginal (5%) better ride comfort? What will be the best choice for downsizing to get a good/considerable response in comfort and also keep good handling ?
I read on some forums that MB went with the 18" wheels on this model so they can minimize the leaning when cornering ( as it is a taller car) so therefore improve the stability of the car.
If downsizing do you think that will change? Will I get a lot of leaning? Will the stability of the car be compromised?
Thank you very much for taking your time to read my post. Looking forward to reading your advice/opinions.

 

[rifiki]

I changed from 17 to 16 inch on my CLK, marginal better ride, tyres about 30% cheaper and may last longer. Handling for normal road use about the same and less tyre noise.

 

[BTB 500]

I changed my SL from 17" to 18" rims and didn't notice any difference TBH.

Actually I suspect the make/model of tyre is more significant than a small increase/decrease in sidewall height.

 

[PobodY]

Try dropping the tyre pressure first? - I suspect the answer is actually softer springs, but that's a lot more work than changing the tyre size.

 

[MikeInWimbledon]

Yes and no: it's wheel size and car specification.

No question about it, smaller wheels will improve the compliance of your ride BUT

The BUT is that the Sport also has brings stiffer dampers, a 20mm lower ride height, which all combine to give you a worse ride than the SE on 17 inch wheels.

The upside to all this is that the Sport corners better than the model than the previous model.

"Thanks Mike, but what does this mean for me...?"

Well, before you just change the wheels, I'd advise you to take a test drive in a B200 SE with 17 inch wheels and see what the difference is. Realistically, you probably only want to change your wheel size, but before faffing around, test drive another car to see if it's anywhere near what you want.

My concern is that if you just swop wheels from 18 to 17, you may find that it's not enough of a change to solve your problem.

The B Class is a great, practical suburban car, but it has its own limitations.

 

[BaldGuy]

These are the sizes of wheel and tyre for your car Sepsi, wasnt sure if you had Diesel or Petrol... I have some mint 700 mile only Michelin Cross Climate tyres for sale if it helps... in 205/55/16...

Mercedes-Benz B-Class 2013 B 200
– Generation: II (W246) [2011 .. 2014]
– Power: 154 hp | 115 kW | 156 PS
– Engine: I4, Petrol
– Center Bore: 66.6 mm
– Lug Size: M14 x 1.5
– Wheel Fasteners: Lug bolts
– Trim Production: [2011 .. 2014]
Tire Rim PCD
205/55R16 6.5Jx16 ET49 5x112
205/50R17 6.5Jx17 ET49 5x112
225/45R17 7.5Jx17 ET52.5 5x112
225/40R18 7.5Jx18 ET52 5x112

Mercedes-Benz B-Class 2013 B 200 CDI
– Generation: II (W246) [2011 .. 2014]
– Power: 134 hp | 100 kW | 136 PS
– Engine: I4, Diesel
– Center Bore: 66.6 mm
– Lug Size: M14 x 1.5
– Wheel Fasteners: Lug bolts
– Trim Production: [2011 .. 2014]
Tire Rim PCD
205/55R16 6.5Jx16 ET49 5x112
205/50R17 6.5Jx17 ET49 5x112
225/45R17 7.5Jx17 ET52.5 5x112
225/40R18 7.5Jx18 ET52 5x112

 

[RichardF]

18>17 won't make a marked difference. I'd wait until the tyres need replacing then (if I hadn't got used to it) swap for 16"

 

[fabes]

Tyre pressure is the first and easiest (and often the most effective) stab at 'ride'

Before recommending to drop them by 3psi (when cold) what are they ALL at (some difference front to rear)?

Brands do make a difference (cross climates get a good rep in the media), but have a look at and please report back on pressures first.

 

[Mr Filipov]

Goodyear eagle f1 is a very forgiving and quiet tyre, yet it is not expensive and has very good stats.

 

[markjay]

Both my previous car (W203) and my current one (W204) were deliberately chosen with comfort suspension (Classic/Executive respectively) and 16" wheels for this very reason.

I was surprised to find that these modeld were relatively uncommon.... the Sport or AMG Line with lowered/stiffened suspension and 17" wheels seem to be the model of choice for many these days.

In addition where possible I chose comfort tyres, e.g. ContiPremiumContact over ContiSportContact.

The car is very softly sprung and handles speedbumps with ease. I don't corner hard and it is more than satisfactory for the odd spirited B-road drive.

I suspect the only way to improve over this would be by opting for a higher-end model with air suspension or any of the models with electronically adjustable suspension.

As for tyre pressure, the W203 was at its best with the pressures set to the higher figure in the range, while the W204 is optimal with the pressure set at the lower figure.

In terms of tread longetivity and mpg the higher pressures are better, and it is worth noting that I didn't find the ride harsh or 'crashing', instead the car seemed to bounce more, but in a soft way ie not 'hard' in the same way that lowered/stiffened suspension feels.

(Obviously having a 'bouncy' car does not aid sporty driving, instead it's mostly a nuicsance)

 

[wu56Shoozz]

Another question that's not raised - what type of suspension is on the car "Sports" or "Comfort" ? I spoke with some one recently that had a E320 with sports suspension on it and it rattled his teeth ..so he change to the comfort suspension and claimed it to be night & day.. just a thought like..

 

[fabes]

It's sport suspension, so the OP has that to cope with

Tyre pressures should be the first port of call

 

[markjay]

Another question that's not raised - what type of suspension is on the car "Sports" or "Comfort" ? I spoke with some one recently that had a E320 with sports suspension on it and it rattled his teeth ..so he change to the comfort suspension and claimed it to be night & day.. just a thought like..

Tyres with higher/softer sidewalls and lower pressures will help, but ultimately - as above.......

The key issue with lowered/stiffened sport suspension is the short spring travel, as well as the springs' rate.

Other components often found in sport suspensions such as sport shocks and thicker anti-roll bars etc will have lees of an effect in comparison.

 

[Dickie Fix]

We tested both the Sport and SE versions when choosing our B200 and noticed a significant difference in ride comfort between the two. The differences were not just wheel size and profile; the Sport had run-flats and different springs which give a 25mm lower ride height.

Try to find a 2013 SE version to compare the ride quality to yours before you commit to spending a shed load of dosh, to see if it is worth it. Comments on other forums have noted an improvement by just changing from run-flats to normal tyres.

 

[Sepsi]

Hi all,

Thank you very much for all your advice. It is nice to see there are still people passionate about cars.
I have read all your comments and I think they are all valid points.
So I had gatehered as much information as I could:
- the car is B200 1.8L CDI 136bhp sport (as per MB book)
- suspension on the car is sport-confort ( as it says in the MB book)
- wheels size are: 225/40 R18 J7.5 Y
- at the moment none of the 4 tyres is the same:
- F driver side: Michelin Pilot Sport
- F passenger side Dunlop SPS Sport Maxx GT
- B driver side Pirelli P Zero Rosso
- B passenger side Continental Contisport5.
- The tyres vary in thread depth with the worst needing a change soon and the best beeing at mid point of thread.
- I dont think any of the tyres is runflat, or at least I couldnt find any markings on them to say that.
- the tyres are running at the pressures stated in the MB book ( I know those pressures are the best for getting best confort-performance ratio,), I know from a safety point of view I should run all of them at or just above 40psi( learned that at a "defensive driving course"), I'd rather no to go under the pressures stated in the MB manual for safety reasons.

I would like to test drive (as some of you sugested) a B200 SE model on smaller wheels to see the difference. How would you suggest to do that? Just go to any dealer which may have one for sale and (lie) look interested as in buying one ? and ask for a test drive? Is that what I should do?


Many thanks
Sepsi

 

[BaldGuy]

Exactly that Sepsi..... Pop to a dealer and express an interest in a particular model... make all the right sounds... do what you need to and politely say "many thanks... my wife and I need to dscuss this further" and leave

I'd be a bit wary about running 4 different brands... that automatically shouts weird ride in any car due to different tread patterns, general brand differences and manufacturing etc etc... I think correct if I'm wrong anyone else thats not going to help things....

 

[grober]

The one snag you may run into on wheel "downsizing" is brake caliper clearance. Some MB "sport" models have larger diameter front discs/calipers meaning you can only normally go down one wheel diameter size. May not apply in your case but something to watch out for?

 

[MikeInWimbledon]

Yes, a test drive BUT....

I would like to test drive (as some of you sugested) a B200 SE model on smaller wheels to see the difference. How would you suggest to do that? Just go to any dealer which may have one for sale and (lie) look interested as in buying one ? and ask for a test drive? Is that what I should do?
Many thanks
Sepsi

Sorry, but step 1 is: take a test drive in a B200 Sport with 17 inch wheels. This will enable you to see what spending a small amount of money changing your existing car to smaller wheels will do.

Then if that's not enough, step 2 is to take a test drive in a B200 SE with 17, or even 16, inch wheels. That will show you what changing car completely will do.

I hope that you'll be happier with smaller wheels, as that'll be cheaper than swopping the car.

Bear in mind that usually changing to smaller wheels is cheap. Every idjit changes in the other direction, so smaller wheels are easily and cheaply bought on eBay less than your old wheels. (I've done its few times in the past - it transforms the handling of a Porsche )

No need to feel guilty about taking any car for a test drive. Call it "Public education."

 

[MikeInWimbledon]

But the B200 does have a hard ride

Despite what I've just said above, going back to my original comment, the B class does have a chronically hard ride and it's really hard in the Sports spec car.

Which is fine for BMW drivers, but not so much for those used to something civilised, like a Mercedes E class.

Here's a thread from (cough) another place, which ruminates on the B class issue:

B class short term review: | Mercedes-Benz Owners' Forums

 

[cooks]

Hi just been reading the thread very interesting as i am picking up A class 180 sport tomorrow, would i get similar ride with that to..