Drilled disc

Who drills them

These folks can drill them and can resurface them. ed

www.truedisk.net/Home.php

Is the drilling supposed to increase cooling rate on the disk?

bountyhunter wrote: Is the drilling supposed to increase cooling rate on the disk?

I think the main purpose is to improve wet braking. In theory the water has a place to go rather than making the pads hydroplane on the rotors. Can't really prove it by me since I have never had problems braking in rain even though my rotors are not drilled, but I suspect there is some advantage to it since so many newer rotors are drilled. Ed

Interesting, never thought of that. I did net research and the two reasons I saw listed repeatedly were:

1) Improves cooling in applications where you do severe braking because air going through the holes.

2) Improves "grab" because the pads can grab the edges of the holes better.

Obviously, the drilling reduces the rotor mass so it would saturate with heat sooner.

Some said that for "normal" applications, better not to use them but they help for racing.

I have never tried the holes but since bike rotors ride out in the air, I would think they would be getting pretty good airflow (?)

650ed wrote:

bountyhunter wrote: Is the drilling supposed to increase cooling rate on the disk?

I think the main purpose is to improve wet braking. In theory the water has a place to go rather than making the pads hydroplane on the rotors. Can't really prove it by me since I have never had problems braking in rain even though my rotors are not drilled, but I suspect there is some advantage to it since so many newer rotors are drilled. Ed

The other thing I personally noticed from the mid 80's to "modern" times is that in the mid 80's, my '86 Dodge had big, heavy one-piece cast iron rotors that cost $16 new. Worked great, dirt cheap. The new cars seem to be using the smaller diameter, lighter dual disc steel rotors where the discs are separated by blocks so air flows between them. That supposedly gives a lighter rotor assembly..... but the downside is they cost about $300 each because they are a complicated assembly instead of a cheap cast iron piece. The other thing I noticed is the thin rotors warp like a mofo. Both my wife's Saturn and my Chevy warp rotors and I get sick of it.

Could add "reduced unsprung weight" to the benefits.
The more holes, the less weight.




Hey! Those holes are way too little! Let's hog'em out some! :woohoo:

Good Fortune!

Holes are good. Lets have lots of them!

For rotors that really dissipate heat fast ceramics is the answer. You can see ceramic brakes on hot race cars glow red/white hot when they touch the brakes then stop glowing the instant they let off the brakes. That's because they shed heat and cool off that quickly.

Here's an example of how outrageously fast ceramics cool. This isn't a brake application, but it's a block of ceramic that has been in a 2,200 degree oven for hours. Pull it out of the oven and pick it up right away with your bare hands - now that's something that is dissipating heat quickly! Don't try this with steel! :laugh: :laugh: Ed

WOW, that's amazing !!! :ohmy: :ohmy:

I switched to dual drilled disks on my bike because I could not get the single non drilled disk to quit squealing when I stopped :pinch:
They are working great and are very quiet
TRUE DISK looks like they know what they are doing

Patton wrote: Could add "reduced unsprung weight" to the benefits.
The more holes, the less weight.

Hey! Those holes are way too little! Let's hog'em out some! :woohoo:

Good Fortune!

I did mine RC style 3 rows of 36 5/16ths holes many years ago in a machine shop I worked at ...... knocked off around 1 and a quarter lbs.