Anyone know anything about Rotor Disc rotors? They are sold by Mini Sport - UK.

thanks

 

From-
http://www.minisport.com/new-mini-sh...-products.html
It's not cheap.

Part number: NMPRDN1125
£144.69
£170.01 inc. VAT
Rotor Discs are a direct replacement for original discs without any modification to improve stopping power and increase deceleration. The design encourages air flow through the disc, enhancing cooling.* The reduced weight of approximately 10% makes them the lightest direct replacement discs on the market.

I think these are going to be good looking but you'd get more performance out of getting better brake pads for whatever you want- autocross, street or track use and maybe upgrading the brake fluid but only if you are boiling the stock fluid.

Many vendors sell rotors only like Webbmotorsports, Helix13.com, Outmotoring.com, tirerack.com and MINImania.com

Anything more than Powerslot rotors (with dimples, or holes) is basically for appearance sake and may reduce the surface area of the disc and wouldn't be helpful from a performance viewpoint.

 

Great info minihune! I really like them a lot.
Does anyone know if they will fit on 15 inch wheels? Thanks in advance.:smile:

 

If they're a direct replacement of the OEM rotors, there should be no problem! :smile:

 

Yes, they should fit but when you order then just ask the vendor if the diameter of the rotor is OEM sized and if it is then it should be fine for stock calipers and for MC and MCS alike in 15" through 17" wheel size.

They are different looking.

 

Yes, and 'improved stopping power' is a rather subjective term. The rotor is the same OD, slots may 'enhance' the pads performance but that's about all.

Right on regarding the pads. Only down side is that reduction of "about 10%" mass may not prove to be such a good thing either....that does not improve stopping power but rather limits thermal capaicity, thus perhaps reducing the effectiveness at the higher end.

Still my hat's off, that's a cool look. Reminds me of the flower power rotors only not quite so extreme.

 

I appreciate comments.:smile:
Hey, if one got those rotors and added upgraded pads and brake fluid for an MC with 15 inch wheels, that could be the best brakes available (for 15 inch wheels). Being 10% lighter would help acceleration, as that may account for a reduction of maybe 2 lbs per rotor(?) x 4 wheels is 8 lbs total x factor of 4 (for rotating mass) is a perceived weight savings of 32 lbs. Sounds quite nice!
I'm not aware of any other improved rotors for 15 inch wheels.

 

I personally would not be inerested in these rotors. This design reduces surface area where you need it the most which is at the outer radius. You will have less leverage as if you have switched to smaller rotors. Also I can't see how this design promotes even pad wear. The out edge could act like cheese grators on the outer half of your pads. I would put my money into better pads first, power slot or SP Rotors second, or a real big brake upgrade kit. I have seen scalloped rotors on show cars with lot of bling and on some dirt track cars that barely use their brakes.

 

There are many options for better brakes using other rotors if you are interested in brake performance.

These rotors are basically a novel design with more form changes than functional benefits. Sure there may be up to 10% weight reduction (13 pound stock rotor for the front and 8 pounds for the back, I weighed them) but if anything the diameter of the rotor is smaller than stock and the number of grooves is quite a bit which would tend to wear the pad faster (another reason why not to get slotted and drilled/dimpled).

For 15" wheels the best no nonsense simple approach is-
Keep the stock rotors or if you must change then consider Powerslot rotors (zinc plated to resist rust a little and few slots) and no dimples.
Brake pads that are appropriate for your desired use- EBC green or Mintex redbox for street, Ferrodo DS2500 or Mintex M1144 for autocross and light track use, or equivalent.
Change the brake fluid only if you have been getting fade or boiled your stock fluid- consider ATE 2000 or superblue.
Keep your stock brake lines or if you don't mind a little firmer feel then Stainless steel brake lines.

So, this means start with the pads and check for brake fade with use. No fade no further changes needed. Rotor change next but not mandatory.

Alot of rotor replacement is for appearance rather than true need. And if appearance is important to you then great.

If I had to loose weight I do it in the rims and tires and not the rotors.
A 2700 pound MINI stopping on a smaller diameter rotor means more heat generated which mean more stress/wear on that rotor unless there is some way to reduce that heat. If you change to that rotor you might want to change brake fluid to handle more heat. More heat will wear off that plating which resists rust.

 

Minihune, Ditto!

 

Wow, thanks guys!

 

....sure, now you guys want me to try and come up with a kit for 15's?....lol

Glad to see smarter heads prevail here on this part.

 

I'm primarily interested in weight savings since the rotors are rotating mass. I just have the CVT MINI and reducing weight would help performance for both speed and braking. Minihune mentioned there are Powerslots and a few others that will work with 15 inch wheels. They may be (probably are) at least a little lighter than stock.

Basically, I'm exploring ways to both get better braking and lighten the car. 15 inch wheels will outperform the larger wheels (for speed), so these are my first choice. If my strategy is not wise or not doable, I may have to resort to larger 16 inch wheels. M7 is coming out with titanium/ceramic brakes for the front that are lighter (with rear to follow), and I wonder if that combo on light 16 inch wheels/tire combo will be lighter than something in a 15 inch combo. So, if M7 can make better brakes that will work for 16 inch wheels, it can be done for 15 inch wheels -- however, I don't know if there would be much demand, as it seems like people want large wheels, and the trend in the auto industry is to make large wheels. I like lighter smaller wheels that are much faster and look better to me.

Anyway, I may just give up on all this and get an automatic turbo MCS down the road. Seems like when I discuss improvements to the CVT MINI I run into resistance and negativity, and end up having to defend it. I can spend $15k to $20k and more upgrading my CVT MINI down the road (I've got $29k into her now) or just get an automatic turbo MCS, and I'm 50/50 on that decision -- I go back and forth.

I appreciate everyone's input, and I do understand now that generally speaking the larger the diameter of the brake rotor the better it can dissipate heat. So, larger is better.:smile:

 

Sorry if any of us sounded like we where pounding on your idea. Getting lighter brakes that also perform better while fitting in your 15" wheels is just a little tough to do unless you go to ceramic coated titanium rotors. The problem with this is that these kind of rotors are usually part of a massive brake system that would never fit inside a 15" wheel. You could search around for such a rotor and make your own system. I have designed my own systems many times in the past. With cast iron stock type rotors you are very limited as lightening the rotor also decreases the surface area so you can go lighter at the expense of performance. If you swapped to 16's or 17's you can find some very light wheels that would accept larger brakes. auto manufactureres tend to use the largest brakes that will fit in the stock wheel. since the base wheel in a Mini is a 15" they designed a brake system to fit comfortably in that wheel. I have designed some systems for racer and most of them didn't care much about the weight of the brakes and preferred to save weight in the wheels/tires. One thing I have noticed with the Mini is the stock front spindle assembly weighs a ton!! Now if somone could cast this in aluminum like many other modern performance cars the weight savings would be huge.

 

Thanks RLmini and others,

Sorry if I went on and on and vented a little. I really appreciate everyone's expert advice and experience. I know that trying to add performance using 15 inch wheels may not be popular or very doable. I'm trying to think of ways, though. I don't have the knowledge or capabilities to be able to design a brake, but I respect those who can. As minihune pointed out, there are some choices in brakes to improve performance that will fit 15 inch wheels. Yeah, maybe someone will make a light front spindle assembly -- I don't know what that is, but weight is the enemy! I'm thinking it's the piece that holds the pad, and if so, it's not rotating weight, but weight nonetheless, and at the front of the car = bad. Anyway, thanks again everyone!

 

I have a spindle that I bought from a wrecking yard for a special project. The part that holds the pad is the caliper. The part I am refering to is incredibly heavy. the top side holds the bottom of the Mcpherson strut and the bottom has a ball joint that attaches to the lower control arm. In the middle is the stub axle that holds the bearings, hub, rotor, caliper and wheels on. Most Mini owners have never tried to pick this thing up and would be amazed and disappointed at its weight. Corvettes for example have gone to aluminum spindles and A arms.

I you are really serious about going with a really light weight system for the 15" wheel assembly that also doesn't decrease performance PM me with a phone number and I will tell you how to design a system and the leads/suppliers to get in touch with.

 

Wow! I appreciate this offer RLmini. I'm not able at this time due to finances as I bought the car on credit and we did some house renovations. Also, I am not sure if I want to commit to that effort, as I am thinking of getting the automatic turbo MCS -- but that is far down the road and still undecided - but leaning towards that more and more. But you've got me thinking. It sounds really good. It probably would be expensive, highly involved, and you may save maybe 100 lbs or so (I'm guessing). Which is a lot, and at the front. If so, that's 5% savings. Originally, when I bought the MINI I wanted to save 10% weight (i.e., 200 lbs or so), but since then do not believe that's doable, so have cut that back to 10% (100 lbs) or more. But I'm thinking to really increase performance for the CVT MINI you would need to trim 400 lbs (and I've heard minihune use that number too), and that's probably impossible, without severe mods. Any weight savings is a plus, and a savings of 100 lbs should be noticed. Anyway it's a good idea, but I'll probably try to trim weight in smaller ways. But I like that thinking. I tend to think in the extreme sometimes. I had thought that to really cut weight on this car, you really need to replace the frame and replace it with a titanium frame, but that would be expensive if doable at all, and if the MINI has a frame integrated with the body, then impossible. The MINI is actually fairly heavy for its size. By comparison, the Toyota Echo has a smaller engine (1.5), 108 hp and weighs 2035 lbs. I drove it as a rental with auto transmission and it is quite quick off the line. I was impressed. I think it is quicker than the CVT MINI off the line at least (if I remember right). (Of course it handles and steers aweful.) So, weight is a big thing.

Thanks again and I'd like to think more about this. Have a great day!:smile:

 

I think you are looking in the wrong place to loose rotating weight.
Make the brakes work but don't worry about the weight of the rotors. Change the pads and the fluid if you need to and stop there. Save your money for where it counts and that is in rims and tires.

What wheels do you have now? With 15" rims you have a choice of 15x6, 15x6.5 or 15x7". The narrow rims are lighter but not as well suited for performance tires. If you like doing autocross or track you can go stock size which is 15x5.5" (you'd have to shoehorn a wide tire on that rim but it is possible) and run H-stock or go wider rims and run in STS.

The good thing about 15" wheels is that the weights are low without having to pay that much, around 12 to 15 pounds each and tires are around 21 pounds. You stock rims if 15" are 12 pounds for the 7 hole design and 15 pounds for the 8 spoke design. Tires are about 14 pounds for the Continental 175/65-15.

Really light 15" rims are in the 8.5 to 11 pound range but are more expensive like Volk TE-37 or SSR Comps. You can try to do a custom job on the brakes but you won't loose that much weight to make it worth loosing brake power or compromising the brake's ability to handle heat.

On the automatic MCS for 2005- it is not a CVT so I don't know how it would compare to your MC. Your MC is lighter and while it lacks power you have to look for ways to reduce weight. Having a good intake (even a good drop in filter) and cat-back exhaust will help an MC.

 

Thanks for ideas minihune. I've got the 15 inch 8 spokes with Continental 175/65/15 tires, so that's a total weight of about 29 lbs. per corner there. I'm ok with this for now, but do want to upgrade later -- not for awhile yet. When I do, I don't see much savings there as you're right, this is already fairly light. If I don't specifically try to keep the weight down there, I could easily get aftermarket wheel /tires that are much heavier. Even though it's a ways off, I still like to think about it all and have a plan. Upgrading to an MCS say in 5 years is getting more probable, so I don't know to what extent I'll do any modding to my CVT MC now, but here's some of my ideas for upgrading the CVT MC I've been thinking about. I would probably let my nephew have my CVT MC for a real low price, so any mods would not go to waste. He told me about the MINI after his girl friend got one.

A good combo I've been thinking about is 15 inch SSR comps in 6 1/2 inch width (maybe 10.5 lbs or less) (as I've heard you recommend the 6 1/2 width for MCs) with Toyo Proxes T1-S in 195/55/15 (only 16.5 lbs in this smaller size) for a total of 27 lbs, for a 2 lbs savings -- not much but I'll take what I can get. Plus the rolling diameter of this is 23.5 inches versus about 24 inches for stock, so that will help with speed a little bit, although throwing off speedometer slightly. The load rating is 85 versus 84 stock, and the speed rating is V versus H for stock, so that's an improvement. I also like the Volks and they are lighter, but I don't think they have a center cap if I remember, and I think you need to add longer wheel studs to be able to mount them.

I also like the wider fender flares (only available for the MC) from Moss Motors -- they call them wide body arch kit -- for $579.95, and are in fiberglass, which are direct replacements for the stock factory wheel arch extensions. They would look even better if the wheels had spacers and were extended out a little farther, but I doubt I would add the spacers.

I'm afraid that if I just changed pads without rotors too I may get some squeeling (that's happened to a few here I've read about). As you mentioned there are some rotors available for 15 inch wheels that will provide better stopping -- I think they are lighter too. But I like your idea of just getting pads -- as the CVT already provides extreme engine braking, one thing I really like about it.

Another thing is to get the head ported and polished with a Schrick cam, header, intake manifold, throttle body, and ECU. Don't know which of these I'll get to now. Maybe just the head and cam. Again, down the road aways.

I haven't done any auto cross or track, but I would like to take her out on the track from time to time, but not until I upgrade tires (later). But even then I'm not interested in going as fast as the car can go (nor in slamming on the brakes just before each turn and really taxing them that much), just in going out there and still going fast, but at my own pace and just have fun.

These are all possibilities. Thanks for the advice minihune! Those are great pictures I saw the other day of your Hawaii car club trip up the mountain. That looked like fun! Take Care!

Area51 -- Sorry if we got off track with your thread at times, but I think we both have learned some things about brakes now thanks to all the above posts by everyone.

And thanks to all above for your expert comments and advice.