What's the point of bell + disc design?

[ILoveMondeo]

Afternoon all,

I've got a really early Tuscan Red Rose which has the old separate bell and disc setup at the front.

What's the point of this design when compared to a one-piece disc?

Also, as an aside, if I need new disc and cant find the separate disc, it looks like the 322 mm Tuscan S discs should be a direct replacement, Sound about right?

cheers

Dave

[blueg33]

Isn't it to save weight? I think (although may be wrong) you can make the bell out of a lighter material

[Walford]

These may fit

http://www.godspeedbrakes.co.uk/~godspeed/product....

[ILoveMondeo]

blueg33 said:

Isn't it to save weight? I think (although may be wrong) you can make the bell out of a lighter material

Makes sense, I was thinking weight or something to do with heat. But thought I'd ask here as PH knows everything!

Thanks for the link walford

[blueg33]

ILoveMondeo said:

blueg33 said:

Isn't it to save weight? I think (although may be wrong) you can make the bell out of a lighter material

Makes sense, I was thinking weight or something to do with heat. But thought I'd ask here as PH knows everything!

Thanks for the link walford

I have since done research, weight is the key point, rotors are often iron but bells are usually billet aluminium. Further its easier to machine a separaet rotor to remove lips etc.

[selym]

I was told the two piece design takes heat away from the braking process.

[blueg33]

selym said:

I was told the two piece design takes heat away from the braking process.

I wondor how that works? Braking is all about converting kinetic energy into heat energy, the rotors are the part that dissipate most of the heat. Perhaps it reduces the heat in the wheel hub, but I can't see how it takes the heat away from the process, as heat is intrinsic to the process.

If heat isn't created, the car wont stop

[selym]

The heat I am talking about is unwanted, causing brake fade, hot spots and in extreme cases, warping of discs.
Check any manufacturer of high end two piece bells and rotors and their main selling point is heart dissipation for those very reasons.