Quality Machine Co.lightened OEM rotors

[nycstripes]

I just got my OEM rotors back from Jim at Quality Machine Co. He cut the front and rear rotors in a wave pattern for me. Can't mount them up yet, my forks are out for upgrades. Turn around time was just over a week.



Rear Rotor
$77 plus shipping costs
Front Rotors
$87 each plus shipping costs
Tax Included
Shipping Rates
$12 for one
$15 for two
$20 for three
Total Cost was $271 including return shipping for all three rotors.

http://qualitymachineco.com/Form/Order%20Form.pdf
Print out the online form and pack up your rotors and send the rotors to:
Jimmy Chance
Quality Machine Co
600 W Lathrop Ave
Savannah, Ga 31415
912-232-5680 office
http://qualitymachineco.com/

[pal2468]

Looks good, when you decrease the rotor surface area, do you decrease the rotors performance in anyway? Post pics when you get your forks back.

[Bleakster]

I had my rear rotor done by them. Great service!

The rear rotor lost 11 oz.

I'll post some pics of the rotor on the bike later.

[bean]

Originally Posted by pal2468

Looks good, when you decrease the rotor surface area, do you decrease the rotors performance in anyway? Post pics when you get your forks back.

+1 does this decrease performance? Is there any advantage braking other than aesthetics?

[Bleakster]

In theory one would think that losing rotor surface area would decrease braking performance. Therefore, being unsure about this matter I decided not to do my front rotors. Doing the rear is not as big a deal since you dont use the rear brake all that much anyway. I was more interested in weight savings. Losing 10-11 ounces of rotating mass is like removing 2-3 lbs of total weight off the bike. (Depending on what formula you use.)

Notes:

One thing I did hear about maching out rotors in this fashion is that it tends to increase brake pad wear. (not sure how true this is)

Also, these types of rotors are not legal for some forms of racing.
For instance, AMA does not allow you to manipulate the outside edge of the rotor surface, while CCS does. To be 100% sure always check your rule books.

[Grady]

Originally Posted by bean

+1 does this decrease performance? Is there any advantage braking other than aesthetics?

You supposedly end up with a brake setup that will be less prone to fading because the disc has a larger surface area for the heat to radiate away. That is along with the benefits of having less rotational mass. But I am not sure if those benefits are enough to cancel out the loss of some surface area for the pads to bite on. Kawasaki seems to think it works and so offer them on the ZX's, the other manufacturers not so much.

[nycstripes]

I will post my findings after my next track day later this month. Since I have two sets of rotors, I can afford to play with these and revert back to OEM rotors if I need to. I would imagine that they can't be that much different than the aftermarket wave rotors out there at much less cost.

[shmike]

Originally Posted by Bleakster

Also, these types of rotors are not legal for some forms of racing.
For instance, AMA does not allow you to manipulate the outside edge of the rotor surface, while CCS does. To be 100% sure always check your rule books.

Depends on what class you are running.

CCS does not allow for changing/machining of front rotors in many classes which is why mine aren't done.

The ones posted here look great, though. I should send my rear to them.

[morsetaper2]

from an engineers perspective...

F=u*N, where...

u=friction coefficient between the pad & rotor, a function of both materials

N=Normal force, AKA the force pushing the rotor and pad surface together, caused by the caliper piston, reduced by any flex in the system

F=Force of friction, AKA the resultant braking force that slows the bike down

Looking at that equation, when the force applied by the caliper goes up, or the friction coefficient is increased, you get more braking force to slow you down.

***************

The Normal force "N", may be substituted by: N=P/A

P=Pressure of the pad material on the rotor surface

A=Area of pad contacting rotor surface

Substituting terms the resulting equation can be written:

F=u*P/A

Reduce the area, the force of friction goes up, equating better stopping power. I think this is a gross oversimplification, I'm reluctant to fully believe in this w/o some hard testing data. What you can be sure of is that more heat per unit volume will end up into the rotor if more braking force "F" is achieved. You also have to have a sufficiently rigid and stiff fork/caliper mount to take advantage of additional braking force gains.

Also, when rotors get hot, they warp, misbehave, braking performance decreases, etc, etc.

In a track situation, the rotors will get used much more severely than your usual street situation. Barring the availability of any hard data, I would look at the SS rotors of the top team(s) that run in a series that allow complete rotor modification to determine the safe, useful, and appropriate level to modify your stock rotors.

But in the end, I think most of you guys would be better served putting your fat ass on a diet!

[Bleakster]

Originally Posted by shmike

Depends on what class you are running.

CCS does not allow for changing/machining of front rotors in many classes which is why mine aren't done.

The ones posted here look great, though. I should send my rear to them.

Thanks for the tip!