Going for Smaller tyres than stock 225 55 16r

[556129]

Thinking of putting 205/55/16 Dunlop Formula D05 tyres on my 520i despite the stock tyres being 225.

The Dunlops are going for an affordable RM240 a piece.

Anyone have tried them, or used smaller width tyres than stock on your 39? Hope it can fit the rims.

 

[Vincent Hor]

Sure 206/55/16 will fit. However there are some measurement differences.
Sidewall height 225 = 123.75mm
205 = 112.75mm
Overall diameter 225 = 653.90mm
205 = 631.90mm
Radius 225 = 326.95mm 205 = 315.95mm
Circumference 225 = 2054.29mm
205 = 1985.17mm
Rev per mile 225 = 807.95/mi
205 = 836.08/mi
Actual 225 = 100kph 205 = 96.64kph
Basically your speedo will be wrong by 3.48%
Hope this helps.

 

[556129]

Thanks bro for the detailed reply, looks like it will help acceleration too with the smaller diameter

 

[Vincent Hor]

Here is a link that will help you to compare tyre sizes

http://www.1010tires.com/Tools/Tire-Size-Calculator

Although you can run on 205 but the gap between tyre to fender will be bigger. Car may look a bit funny.
You could also loose a bit of comfort due to lesser tyre side wall height.

 

[airtube]

These is a lot of effect on the vehicle when you change tyre size. Most people don't know and some don't look at the effect as a major impact. Basically your Vehicle dynamic character is affected. Maneuvering rate and roll center height changes. Affect on meter combi. Ground clearance affected. Watch out on gyre lead index and speed rating which will be lower. Many more. Even your tyre contact patch is reduced. Recommended not to change.

Cheers


Sent from my iPad using Tapatalk

 

[kayzhen911]

ya, better not to change.
I'm sure there are cheap tyres out there
I'm currently using 245/40/18
normally these specs are selling around 700-800
that is for normal tyres....
I'm using accelera tyres from Indonesia and they work great.
costs me only 450/tyre.
so ...... why downgrade till 205?
my 2 cts.....

 

[sewell]

to me i think is OK. because original 520i (2000cc) found in singapore also does come with tyre 205/60/15 tyre.

 

[556129]

These is a lot of effect on the vehicle when you change tyre size. Most people don't know and some don't look at the effect as a major impact. Basically your Vehicle dynamic character is affected. Maneuvering rate and roll center height changes. Affect on meter combi. Ground clearance affected. Watch out on gyre lead index and speed rating which will be lower. Many more. Even your tyre contact patch is reduced. Recommended not to change.
Cheers
Sent from my iPad using Tapatalk

ya, better not to change.
I'm sure there are cheap tyres out there
I'm currently using 245/40/18
normally these specs are selling around 700-800
that is for normal tyres....
I'm using accelera tyres from Indonesia and they work great.
costs me only 450/tyre.
so ...... why downgrade till 205?
my 2 cts.....

Yeah, the tyre shops also recommended me against going down to 205. 215 was the min they suggested. I reckon if i had 15" rims, i could do the 205s with no issue since thats actually a stock size given on the door sticker.

Anyway, i ended up with Hankook Ventus2 Concept 2 for the stock 225/16/55 size for rm350 a piece from the 3s in Ara Damansara.

Doesnt feel as soft as my original conti mc5 but saved a bit over the contis.

Thanks for all the feedback.