10 replies to this topic

[henuz96]

Hi all

I have a 998 1988 mini and have just put a bid in on a set of 13x7 minilight wheals.

I have just be looking on here about them and been seeing some people say that thinner wheels are better aka the original ones.

Plus is there any complications on putting bigger wheels on like speed and the speedo?

I really need some help on what you lot think.

Cheers

Henry

[the_samkingdon15]

if you change your mind, I've got a set of 12X5 minilites I can do cheap.. pretty much new tyres

[Cooperman]

10" or 12" wheels of the original width or very slightly wider are best on all Minis.

 

The wider wheels have several disadvantages.

The first id that they alter the suspension geometry due to the width causing the 'scrub angle ' to be incorrect.

Secondly they put additional load on the suspension joints.

Thirdly they take some suspension compliance away as the tyre walls take less of the suspension shocks which the tyres must take, thus putting extra work onto the dampers and springs.

Fourthly they increase the drag due to the greater cross-sectional area presented to the airflow, thus reducing top speed and needing more fuel at the cruise.

 

But, some people think they look good. Do they look good enough to put up with the downside? Only an owner can answer that as it is his/her car. However, the facts are as above.

[gazza82]

Speedo will be out, as will odometer, unless you get low profile tyres for 13" wheels and keep diameter/circumference of original tyres. Jumping from 10 to 13 will make that difficult. Or get the speedo recalibrated.

[hunterg30]

plus you have to chop your wings ,front panel and A panel to fit them

[Cooperman]

Speedo is not affected by going from 10" to 13" wheels as the low profile of the 13" tyres makes the rolling radius virtually the same as for a 10".
The additional width of the tyres/wheels with 13" means that the wings have to be cut, huge wheel arch extensions fitted 9more aerodynamic drag further slowing the vehicle) and lock-stops need to be fitted to the steering rack to prevent the inside edge of the wide tyres hitting the inner wheel arch on full lock.
Also the damping must be set softer to enable the dampers to do the work normally done by the tyres. If this is not done the road-holding on bumpy corners will suffer due to lack of suspension travel.

[henuz96]

Ow crap. I really shouldn't of bid on these wheels by the sound of it! Hopefully someone else will put a bid in for them as they are still cheap.

If anyone is interested there are on ebay under classic mini alloys. The current bid is £100 by me of course and it is for 4 13x7 white mini light alloys that also come white good tyres.

Thanks for all the help!

Henry

[Cooperman]

With wheels it is always worth remembering that the Mini was designed to have 5-20 x 10 cross-ply tyres or 145/80 x 10 radials on 3.5" wide wheels.

Even the original Cooper 'S' had 3.5" wheels as standard with 4.5" as an option. Tyres were then 145/80 x 10.

As soon as a wider wheel/tyre is fitted it moves the centre-line outwards from the as-designed steering geometry. 

I recently drove a 1997 Cooper MPI with 4.5" Minilites and 145/70 section tyres. It really did feel great on the road and although the road holding in the dry might not have been quite what a 165/60 would have given, the handling was as good as any standard suspension Mini I've driven for a long time.

The 13" wheels were really just a styling gimmick which was introduced at the end of the production run for no good engineering reason. One might suppose that the image stemmed from racing where wide large diameter wheels were used with 'sticky' racing tyres on totally smooth tracks rather than road tyres on bumpy public roads - and they sure are bumpy these days.

But there are owners for whom perceived style is more important than road-holding, handling and performance, so each to his/her own really.

[Mini 360]

Form over function for me when it comes to wheels.  1000s have fitted 7x13s so i wouldnt worry too much ;)

[Cooperman]

Sorry, I'm an engineer by profession and, as in all engineering, I like to see the design optimised. To me anything which reduces the overall performance by increasing the fuel consumption, reducing the speed or making the road-holding and suspension operate less well is an anathema as it is not 'best engineering practice'. In fact it is quite the opposite. 

The appearance is a matter of personal taste, of course, and whilst Rover might have thought the very large diameter wheels improved the appearance and improve the sales figures, others think they look a bit silly and deplore the negative effects on the wonderful classic Mini.

[lager.and.pretzels]

Is it possible that - given modifications made to correct the geometry for the larger wheels - the 13" wheels can bring the Mini into a greater performance envelope considering the larger braking setup and the greater amount of rubber and rubber choices to be made?

 

As a reason for consideration of "broadening the Mini performance envelope":

I'm planning on 300+ horsepower, front engine and rear wheel drive layout.

 

I've been considering 10" v 13" and I'm quite tempted toward the 13" category based on how many freebie tires I could scoop up from SCCA/NASA (North America/Arizona) events with a few heat cycles into them, and then by the number of tire size and compound combinations I could utilize. Since I'm doing a complete engine/powertrain swap, and thus entirely (re)engineering a new suspension (leaning heavily on existing geometry), I figure I have a chance to make best of this option, and throw out (most of the) rest.