cross drilled rotors
12-15-05, 01:51 AM
#28
brake guide.. (not complete, but a start)
Quote:
"From what I have learned about brakes is that if you can lock the tires, thats the max, every thing extra is to add control and feel to your brakes, not to make you stop faster (unless its the pads themselves)- you have the best brakes for the application. This is because if you can lock your tires, you are loosing traction at the tires, not your brakes- at this point your tires are the weakest link in the system. Here are my observations:
Single piston (sliding) VS multi pot calipers (floating):
Imagine if you will: you have a brake pad- and its slightly flexible under load. the more pistons you have the force is distributed evenly thru the brake pad. ie: 1 point of contact per pad- as opposed to multi pot brakes which have 2 or more points of contact on the same pad- the force is distributed in more places, making the brake pad work evenly.
(see figure 1)
Difference between floating and sliding systems:
- you have 1 big piston on one side and it forced the closest brake pad to the rotor- therefor pushing back on the caliper, and the other pad will follow afterwards because the piston is 'pulling' the pads together. Mind you the calipers will flex under load and therefore making the pad move as well.
"
(just dont notice the missing pads on the floating brake)
As far as rotors go, my observations are, larger rotors DEFINATLY add to braking feel and control. The brakes feel like they have more accurate control of 'feathering' traction. Theres also alot more mass to aid in heat resistance and more surface area to aid with cooling (think- more area, same heat= less overall heat per area). Slotted rotors are the way to go. Since gassing isnt so much an issue with brake pads now-a-days (specially if you have ceramic/kevlar or variations of such).
The slotted rotors have a very slight edge to them and will 'eat' away the brake pad faster, but will provide a clean surface for each 'pass' of the brake pad.
Drilled rotors are for old asbestos pads which will generate more 'gas'. they also help lighten the rotors by removing more material. They are prone to cracking, so I would avoid them if you use your brakes heavily, such as races and such.
"From what I have learned about brakes is that if you can lock the tires, thats the max, every thing extra is to add control and feel to your brakes, not to make you stop faster (unless its the pads themselves)- you have the best brakes for the application. This is because if you can lock your tires, you are loosing traction at the tires, not your brakes- at this point your tires are the weakest link in the system. Here are my observations:
Single piston (sliding) VS multi pot calipers (floating):
Imagine if you will: you have a brake pad- and its slightly flexible under load. the more pistons you have the force is distributed evenly thru the brake pad. ie: 1 point of contact per pad- as opposed to multi pot brakes which have 2 or more points of contact on the same pad- the force is distributed in more places, making the brake pad work evenly.
(see figure 1)
Difference between floating and sliding systems:
- you have 1 big piston on one side and it forced the closest brake pad to the rotor- therefor pushing back on the caliper, and the other pad will follow afterwards because the piston is 'pulling' the pads together. Mind you the calipers will flex under load and therefore making the pad move as well.
"(just dont notice the missing pads on the floating brake)
As far as rotors go, my observations are, larger rotors DEFINATLY add to braking feel and control. The brakes feel like they have more accurate control of 'feathering' traction. Theres also alot more mass to aid in heat resistance and more surface area to aid with cooling (think- more area, same heat= less overall heat per area). Slotted rotors are the way to go. Since gassing isnt so much an issue with brake pads now-a-days (specially if you have ceramic/kevlar or variations of such).
The slotted rotors have a very slight edge to them and will 'eat' away the brake pad faster, but will provide a clean surface for each 'pass' of the brake pad.
Drilled rotors are for old asbestos pads which will generate more 'gas'. they also help lighten the rotors by removing more material. They are prone to cracking, so I would avoid them if you use your brakes heavily, such as races and such.
12-15-05, 07:41 AM
#29
RX-heaven- I can be bad with words, I didn't mean to imply there were gas problems, I just thought that along with the cleaning aspect, and the 'expansion joint' of the slot in the pad, that they would also help any gasses escape..(specifically older cars / older pads)
This seems to make sense to me, but oh well... I too don't really understand all this commotion about this outgassing....
That's pretty funny about the bicycles.......
(mine's a type R with carbon fiber wing and a 50 shot of naaaz)
Nice explanation there zero-drift, did you make those drawings? or are they 'off the shelf'?
|M|
This seems to make sense to me, but oh well... I too don't really understand all this commotion about this outgassing....
That's pretty funny about the bicycles.......
(mine's a type R with carbon fiber wing and a 50 shot of naaaz)
Nice explanation there zero-drift, did you make those drawings? or are they 'off the shelf'?
|M|
Last edited by Mordachai; 12-15-05 at 07:44 AM.
12-15-05, 09:35 AM
#30
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Drilled rotors are PERFECTLY SAFE as long as there is only about 3 or 4 holes.
I have x-drilled, slotted rotors on my car from irotors.com. They have 3 holes in a line.
One of these rotors were ground down to HALF its size and still never cracked. I Dorve it like this for about 4 months. If you get rotors with many holes yes i do believe they could crack. Dont tell people they will crack just because its the rumor going around. It depends on the rotor.
My front calipers seized up one day and would not let go of the rotor so i drove home from about 10 minutes while the front brakes were constantly engauged. So bad that I could not go into 4th gear. 3rd would not even accelerate. When I got home the rotors were putting out so much heat I could feel it from 5 feet away. I feel they are very safe.
I have x-drilled, slotted rotors on my car from irotors.com. They have 3 holes in a line.
One of these rotors were ground down to HALF its size and still never cracked. I Dorve it like this for about 4 months. If you get rotors with many holes yes i do believe they could crack. Dont tell people they will crack just because its the rumor going around. It depends on the rotor.
My front calipers seized up one day and would not let go of the rotor so i drove home from about 10 minutes while the front brakes were constantly engauged. So bad that I could not go into 4th gear. 3rd would not even accelerate. When I got home the rotors were putting out so much heat I could feel it from 5 feet away. I feel they are very safe.
Last edited by ViperDude152; 12-15-05 at 09:50 AM.
12-15-05, 10:54 AM
#31
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if you put a strain gauge on a cantilever beam at various points and measure the stress vs the same beam with a hole in it, you can see a high concentration of stress around the area with a hole in it. i'm not saying the rotors will fail, they may or they may not, but there *is* a whole lot more stress on them.
12-15-05, 11:10 AM
#32
prime example of cross drilled rotors that are reliable are on motorcycles. I believe the reason theres last so long is ring that holds the rotor to the 'hat' (which connects to the rim). They use cross drilled rotors becauase it removes large ammounts of mass, and their rotors are not vented like car rotors.
Oh ya-i made the picture w/ paint. XP
Oh ya-i made the picture w/ paint. XP
12-15-05, 11:30 AM
#33
Originally Posted by ZeroDrift
prime example of cross drilled rotors that are reliable are on motorcycles. I believe the reason theres last so long is ring that holds the rotor to the 'hat' (which connects to the rim). They use cross drilled rotors becauase it removes large ammounts of mass, and their rotors are not vented like car rotors.
Oh ya-i made the picture w/ paint. XP
Oh ya-i made the picture w/ paint. XP
12-15-05, 04:09 PM
#34
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Motorcycle brakes compared to cars are HUGE. Motorcycles have a lot less mass (inerta) to stop and radiate their heat better. Theres also a lot less strain on them than what a car has.
You cant compare a motorcycles brakes to a cars brakes, youd need to have 22" rims and GIANT rotors for it to be anywhere near comparable.
You cant compare a motorcycles brakes to a cars brakes, youd need to have 22" rims and GIANT rotors for it to be anywhere near comparable.
12-15-05, 08:49 PM
#35
Ban Peak
iTrader: (49)
If you're looking for rotors, call Gotham Racing, and talk to Brock.
He can get 4 lug and 5 lug, slotted& cross drilled, or one or the other with silver zinc plating.
I got a front set of Silver zinc plated slotted and cross drilled rotors delivered to my door for $150.
It's quick, and they ahve awesome customer service.
I beat the **** out of my brakes, and trust me, these are good rotors.
www.gothamracing.com
He can get 4 lug and 5 lug, slotted& cross drilled, or one or the other with silver zinc plating.
I got a front set of Silver zinc plated slotted and cross drilled rotors delivered to my door for $150.
It's quick, and they ahve awesome customer service.
I beat the **** out of my brakes, and trust me, these are good rotors.
www.gothamracing.com
12-15-05, 09:00 PM
#36
Bikes run drilled rotors for weight reasons. Brake rotors on bikes are only huge DIAMETER wise, the width of the swept area is pretty small. That much metal that far out on the wheel is a lot to move, in the relative terms of a motorcycle. That's that PM says anyway.
I've found slotted rotors to be nicer in the rain on my cars. I would guess the features that made them good to direct outgassing 30 years ago when it mattered helps them to channel water effectively too.
Beyond that, as everyone said, get good pads.
Oh, BTW, Brembo doesn't cast those those with holes, other companies modify them later; In regard to going to a race track and not seeing any cars with drilled rotors, ever seen a higher end Porsche? The vast majority have drilled rotors stock. They also aren't "drilled" but rather cast in that way.
I've found slotted rotors to be nicer in the rain on my cars. I would guess the features that made them good to direct outgassing 30 years ago when it mattered helps them to channel water effectively too.
Beyond that, as everyone said, get good pads.
Oh, BTW, Brembo doesn't cast those those with holes, other companies modify them later; In regard to going to a race track and not seeing any cars with drilled rotors, ever seen a higher end Porsche? The vast majority have drilled rotors stock. They also aren't "drilled" but rather cast in that way.
