Ok, I have 17-inch S-Lites and I really want to ditch them in favor of a lighter tire/wheel combo but I have some questions I hope some NAM members can answer.

I want to go with lighter wheels/tires because I noticed a performance difference with my blizzaks on ASA-JS1 wheels but they don't corner so well. Now will I have a problem with a lighter wheel such as the ssr competition or the Kosei K1 Racing wheel in terms of running over potholes and damaging the wheel? (those are the two I am looking at) I like the weight of the SSR Comps. but I don't like the price. The Kosei K1 is a much better price but at a little more weight. Is one stronger than the other? If the SSR Comps would hold up to potholes better I would probably get that but if they are both about as strong I would probably go with the Kosei's.

Also the size of the wheels... both of the above wheels come in the 17x7.5 how does this compare to a 17x7 wheel and is there really any difference in terms of performance?

Now on to the tires. I understand that there are different tires but I don't know what all the numbers mean. I see things like 205/50-17 or 205/45-17 and I guess the 17 means it is a 17" tire (or fits on a 17" rim) but I am a little confused about the other two. I know they have something to do with the width of the tire and the size of the sidewall but I don't know what size tire I should get. I like the looks of the 17" tire and since I don't plan on lowering my mini I don't think I want to go to a 16". Currently I don't do any racing... just some spirited driving. I like to corner so a smaller sidewall should be better right? But then this has the potential to damage my wheels. So what sizes should I get with the Kosei K1 or SSR Comp wheels?

Now, snow is not an issue because I have a set of blizzaks that I can throw on when it starts to snow but I want a tire that will be ok in rain but perform really well. (I can go a little slower when it rains... not a big deal) I'm really leaning towards the yokohama ES100 because of the favorable reviews. Are there any other tires I should look at?

Also a lot of people recommend switching to a 16" wheel. I imagine this is mostly due to the weight... is there any other reason? I don't autocross yet but I have been thinking about it. I don't plan on trying to win, just going out and having some fun. I guess that's all the background I can think of. Hopefully someone can help me makes some sense of tires and wheels.
-Chris

 

ok, lots of questions! I'll try to answer as direct as possible

Yes, the S-lites are not light at all. A lighter wheel/tire set will definitely improve off-the-line performance as well as making the car "lug" less over bumps.

the infamous 16" vs. 17" vs. 18" debate continues. I feel it mostly depends on your goals and road surface quality. Obviously, you can't run an 18" in pothole riddled roads, unless your wheel and tire budget is more than the cost of your car! Snowbelt states, 16" will be your safest bet. You lucky motorists in the southern states, you can get away with 18's. Personally, 17's look aesthetically balanced and proportional, however the style of the wheel can make the rim diameter look more or less, so keep this in mind too.

There are a good selection of quality lightweight wheels out there. Then again, there is also lots of heavyweight junk and/or poor alloys out there. Sometimes, you get what you pay for; spending extra dough for premium wheel will typically yield premium materials, engineering, and finish, though not intrinsically!

Tire sizing: stock 17" size is 205/45-17. That means the tire width is 205 mm, the sidewall height is 45% of that 205 mm, and the wheel mounting diamter is 17 inches. It's important to keep the overall tire height as identical as possible to stock. Lucky us, MINI chose a rather strange size for the MINI, and we have to fudge the numbers alot for aftermarket, as there are only a handful of tires in the 205/45-17 size. You can go a bit wider: 215/40-17, or a bit wider and taller: 215/45-17. You can go shorter: 205/40-17, or really wide and tall; 225/40-17. Of course, with a wider than stock tire, you may want to get a wider than stock wheel to ensure proper fitment.

Speaking of proper fitment, wheel width, wheel offset, and tire size will play a key role in the combo fitting under your MINI's wheel arches. Stock tire sizes and wheel parameters yield no wheelwell rubbing, and that's good. What's not so good, is the stock sizing tucks the tire under the car, giving a not-so-aggressive look. The offset of the wheel is key here. The smaller the value the further pushed out the wheel will be (i.e. the s-lites are 17x7 with a offset of 50mm, also noted as "ET50&quot The 50mm denotes the distance from the wheel centerline to the wheel-hub face.

Let's do an example: You want Kosei K-1's in 17x7.5, this size for the MINI is an ET45, which will be more flush with the wheel arch yet not too extreme. I'd pick a 215/40-17 to utilize the extra half inch of wheel width and get more rubber on the road. I'd pick the Goodyear GS-D3. It's excellent in the wet, excellent in the dry, and good for occasional track/autocross use too. Also, it's rounded shoulder profile will ensure no wheel arch rubbing, which is a good thing. This wheel/tire combo will give you way lighter weight than stock, as well as dramatically increased grip in all warm-weather conditions. The K-1 is also available in silver or white, to match your preference.

I hope that helps out,
Ryan

 

The famous tire size calclutator. Play with it a little bit and see how your tire selection matches up to the stock size tires.

http://www.miata.net/garage/tirecalc.html

 

Another great thread - maybe we should sticky this? I know the concept of width vs. sidewall, offset, etc. but sometimes it is hard to remember exactly what is what and what the default offset is.

Great job, Ryan - a very concise description.

 

>>Ok, I have 17-inch S-Lites and I really want to ditch them in favor of a lighter tire/wheel combo but I have some questions I hope some NAM members can answer.

Chris,

Ryan's answer is a good start. Also go to tirerack.com and read their technical info stuff on wheels and tires.
Talk to Dan at tirerack for anything you don't understand. What ever you choose has to fit on your MINI and your suspension will limit what wheels you can fit. Stock suspension will give you the greatest flexibility while lowered MINIs will have to be more careful with less choices for wheel offset in order not to rub tires on the wheelwells.

>>I want to go with lighter wheels/tires because I noticed a performance difference with my blizzaks on ASA-JS1 wheels but they don't corner so well. Now will I have a problem with a lighter wheel such as the ssr competition or the Kosei K1 Racing wheel in terms of running over potholes and damaging the wheel? (those are the two I am looking at) I like the weight of the SSR Comps. but I don't like the price. The Kosei K1 is a much better price but at a little more weight. Is one stronger than the other? If the SSR Comps would hold up to potholes better I would probably get that but if they are both about as strong I would probably go with the Kosei's.

A pothole big enough and deep enough hit by any MINI with stock wheel or lightweight wheel will seriously risk damage. The runflat is very stiff and transmits lots of damage to the stock rim. If potholes are a problem in your daily drive then be very careful not to go too light on the rims or go with a stronger design such as forged rather than cast rims (this increases the cost). Cast rims are cheaper but also tend to be heavier.

SSR comps are strong and light (hence the higher price). K1 rims are not as costly but not as strong. They are a good budget rim and should work for most people. You don't want to hit any potholes. If that is common for you then I'd be careful about fragile lightweight rims in your case.

>>Also the size of the wheels... both of the above wheels come in the 17x7.5 how does this compare to a 17x7 wheel and is there really any difference in terms of performance?

17x7 and 17x7.5 are very close. Not that much difference for street use.

>>Now on to the tires. I understand that there are different tires but I don't know what all the numbers mean. I see things like 205/50-17 or 205/45-17 and I guess the 17 means it is a 17" tire (or fits on a 17" rim) but I am a little confused about the other two. I know they have something to do with the width of the tire and the size of the sidewall but I don't know what size tire I should get. I like the looks of the 17" tire and since I don't plan on lowering my mini I don't think I want to go to a 16". Currently I don't do any racing... just some spirited driving. I like to corner so a smaller sidewall should be better right? But then this has the potential to damage my wheels. So what sizes should I get with the Kosei K1 or SSR Comp wheels?

The 205 number refers to 205mm width of the tire and the 45 number is the series of the tire and refers to the sidewall ratio. The lower the number the less tall the side profile and the stiffer the ride with better cornering.
In 16" rims the 45 series is good while in the 17" rims the 40 or 45 series tires are good.

>>Now, snow is not an issue because I have a set of blizzaks that I can throw on when it starts to snow but I want a tire that will be ok in rain but perform really well. (I can go a little slower when it rains... not a big deal) I'm really leaning towards the yokohama ES100 because of the favorable reviews. Are there any other tires I should look at?

ES100s are good for the price and for street driving. The other choices are more expensive and Range from Toyos to Goodyear Eagle F1 DS-G3s to Bridgestone Potenza Pole Position S-03s.

>>Also a lot of people recommend switching to a 16" wheel. I imagine this is mostly due to the weight... is there any other reason? I don't autocross yet but I have been thinking about it.

If you are thinking of autocross then you need to plan ahead and figure out which class of autocross do you want to start with. H-stock for MC and G-stock for MCS? Or if you have mods already then you may be in other classes aready which may have no restrictions on wheels but the stock classes are limited to stock size wheels so 15" and 16" rims in stock widths for the MC and 16" and 17" rims up to stock widths for the MCS.

16" SSR Comp R are legal for stock MC and MCS alike so they are popular but Webbmotorsports.com sells AK Monza 16" rims and wheelsets that are much the same, legal and affordable by comparison. They do weigh more.

16" is a common size for aftermarket wheels because:
Prices tend to be more reasonable then 17" rims or larger
Prices for tires that fit tend to be less costly then similar tires in 17" size or larger
Selection of rims is fairly wide compared to 15" and 18" rims
Minimal rubbing issues with stock and lowered MINIs (still have to choose good rim/tire combo)
Less jarring ride and still decent performance for street and autocross or limited track
Depending on wheel and tire combo can look similar to 17" wheel-from a distance
Rim weight can be lower than a 17" rim of similar design
Better selection of autocross tires that will fit in a MINI, the 17" rims need to be wider to fit tires larger than 215 and that may lead to rubbing issues.

 

Thanks everyone! I've been mulling it over for a while now and I figured I'd let people know what I've decided. I think I'm gonna go with the SSR Competition wheels because they are stronger but then I'm gonna have to go with a cheaper wheel (yoko ES100) and then I can try other wheels once my car fund recovers from buying those wheels. It will probably be another week or two before I can actually order them but I'll try and get some pics up once I get them.
-Chris