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Hi All,

I was hoping someone could explain to me the difference between one and two-piece rotors in regards to construction, durability, stopping power, use in road and/or track applications.

Thanks

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Hi All,

I was hoping someone could explain to me the difference between one and two-piece rotors in regards to

1. construction

2. durability

3. stopping power

4. use in road

5. track applications.

Thanks

My 20 cents worth;

1. One piece rotor is all cast, then hardened. Two piece rotor has a cast disc bolted to an an alloy centre. So it is noticeably lighter and transfers less heat to the wheel bearings, wheels, CV's, uprights etc

2. The durability of the parts around the rotor (wheel bearings etc) are improved by it being two piece. If the rotor is made of the same material and is the same dimensions, then it will not, in itself, be any more durable, Except you don't have to replace the hat when the rotor wears, so in theory it should cost less to service.

3. If the rotors are the same dimensions and solid mount, there is no real difference in stopping power.

4. Probably not worth the extra cost on a road use only car, does have a bit of rice value for some though.

5. Definitely worth doing on a race only car, saves heaps on wheel bearing and CV servicing, plus the lighter unsprung weight is worthwhile having.

Note; not all two piece rotors are the same, for example there are floating and solid mount rotors. A floating rotor definitely improves the braking performance and consistency, as it eliminates/limits pad knock off in many cases.

Hope that helps:cheers:

Rice value SK? So how many extra rwkw can you say you have? How much will the guys be able to outbrake the evil commonwhores by? :wave:

Sorry, just on some particularly good painkillers at the moment.....:D

Just taking this a bit further.  Can we have a bit more elaberate explanation of the floating rotor?

The rotor is attached to the disc by bolts that allow it to move in and out (ie; float). So, when you put your foot on the brake pedal and the pads extend, the rotor is free to self centre between the pads squeezing on it.

If you have a slightly warped rotor, this lowers the amount of pad knock off as the rotor can also self centre when not braking. Since it is loosely mounted, even a slight touch on the pad will line it up ready for the next brake application.

It is very usefull in the longer distance races as we always end up with some rotor warping from the extreme heat loadings. Pit stops add to the warping tendency as the rotors cool down a fair bit, expecially in that slow crawl they make us do down pit lane now.

Hope that helps:cheers:

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