Affect of Rotor Size?
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Affect of Rotor Size?
What is the affect of a Disc Brake rotor size?
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Originally Posted by wheelhot
What is the affect of a Disc Brake rotor size?
you should ask the question a little better... maybe, "How does rotor size affect stopping power?"
Using a larger diameter rotor will increase your stopping power, but you should check with your forks manufacturer to see if the warranty will still be valid for using a larger rotor.
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Not surface area. The greater stopping power from larger diametered discs is because the friction of the pads are applied farther away from the axle. Trying to stop a wheel near the hub. It takes much more force or friction then from farther out.. Rim brakes in theory are best (their braking power is applied as far from the axle as possible)yet are inferior because they work off of the pulling power of your finger w/o a mechanical advantage whereas disc brakes actuate from the power of a screw or hydraulic pressure that is multiplied, to some extent, by the power of your finger.
Did I make that confusing enough? hehe
Did I make that confusing enough? hehe
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Originally Posted by wheelhot
What is the affect of a Disc Brake rotor size?
however it can get kind of complicated since there is another sort of artificial "lever arm" created from the head area on the bike to the tire contact patch on the ground. this is a totally dynamic lever arm obviously. as you ride it comes in contact with the ground to varying degrees to not at all.
so just think about the first example.
then of course you would have more surface area for heat dissipation. however, the torque scenario is the main reason
HOPE mono4 that made sense
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sorry to make you guys confuse. I was in a hurry when i wrote that. Anyway this means that the bigger the diameter the better?
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Originally Posted by wheelhot
Anyway this means that the bigger the diameter the better?
Riding down the side of a big mountain you will want the extra surface area and stopping power.
With an xc bike on flatter terrain the extra surface area is just added weight and the extra power wasted.
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oh i see. Technically im a all type of rider. So which one you suggest?. Cause i dont really go for competition, i usually cycle around (terrain and non-terrain)
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We use 8" rotors on the tandem. That's 203mm. Magura will warrant their brakes for tandem use with slightly smaller rotors. Moral of the story? Even those little 160mm rotors will stop a single with ease.
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Get a set of Avid BB7 mechanical disc brakes with standard 160mm rotors. They are easy to use, easy to adjust, and have good stopping power. Unless you ride a 29er, then I would increase the front brake rotor to 185mm to keep the lever pressure about the same.
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Well, the first time I ever used hydros was my friends Hayes Nines with 6 inch rotors. They had so little power I never wanted to use them again. A month ago he slapped some 8 inch rotors on his bike, and now they make me want to pay extra for them. I know Hayes Nines are not the most powerful brakes there is but just going from 6 inch to 8 inch really made them stick out.
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Originally Posted by free_pizza
i was only kidding about the surface area thing (even though it is true)...
The original poster worded his question poorly...
The original poster worded his question poorly...
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I'm not sure what the terrain is like in Malaysia but if you ride huge hills, a 8" rotor is a really nice to have. I agree, as mentioned by other folks, that the advantages are more stopping power, less heat buildup and ultimatly longer brake pad life.
Below is a pic from the Jumping Pond Ridge/Cox Hill in the Kananaskis area of the Canadian Rockies. I can't image the desent with anything but 8" rotors. One of my riding buddies cooked his pads on his 6" Hayes mechanicals this day.
Cheers
T.J.
On the way up....
Shamless bike porn
The beginning of the descent
EDIT: If you are seriously considering 8" rotors, be sure to check with your fork manufacturer to be sure it can handle the added forces. Some forks are not rated for 8" rotors (I.e. All Fox <04, most X/C forks...)
Below is a pic from the Jumping Pond Ridge/Cox Hill in the Kananaskis area of the Canadian Rockies. I can't image the desent with anything but 8" rotors. One of my riding buddies cooked his pads on his 6" Hayes mechanicals this day.
Cheers
T.J.
On the way up....
Shamless bike porn
The beginning of the descent
EDIT: If you are seriously considering 8" rotors, be sure to check with your fork manufacturer to be sure it can handle the added forces. Some forks are not rated for 8" rotors (I.e. All Fox <04, most X/C forks...)
Last edited by Tequila Joe; 11-23-05 at 09:09 PM.
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Originally Posted by norcodirtjumper
Well, the first time I ever used hydros was my friends Hayes Nines with 6 inch rotors. They had so little power I never wanted to use them again. A month ago he slapped some 8 inch rotors on his bike, and now they make me want to pay extra for them. I know Hayes Nines are not the most powerful brakes there is but just going from 6 inch to 8 inch really made them stick out.
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Originally Posted by Tequila Joe
I'm not sure what the terrain is like in Malaysia but if you ride huge hills, a 8" rotor is a really nice to have. I agree, as mentioned by other folks, that the advantages are more stopping power, less heat buildup and ultimatly longer brake pad life.
Below is a pic from the Jumping Pond Ridge/Cox Hill in the Kananaskis area of the Canadian Rockies. I can't image the desent with anything but 8" rotors. One of my riding buddies cooked his pads on his 6" Hayes mechanicals this day.
Cheers
T.J.
The beginning of the descent
EDIT: If you are seriously considering 8" rotors, be sure to check with your fork manufacturer to be sure it can handle the added forces.
Below is a pic from the Jumping Pond Ridge/Cox Hill in the Kananaskis area of the Canadian Rockies. I can't image the desent with anything but 8" rotors. One of my riding buddies cooked his pads on his 6" Hayes mechanicals this day.
Cheers
T.J.
The beginning of the descent
EDIT: If you are seriously considering 8" rotors, be sure to check with your fork manufacturer to be sure it can handle the added forces.
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Ns view, Malaysia track is something like that and sometime even worst but not very rocky. Its just that our track is very uneven and the gravel is unknown. And is there any other way to know wheter your fork support 8 inch? Cause i cant find any information on my fork
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Originally Posted by KonaRider24
Ok, I need to hit that trail bad.
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Originally Posted by wheelhot
Ns view, Malaysia track is something like that and sometime even worst but not very rocky. Its just that our track is very uneven and the gravel is unknown. And is there any other way to know wheter your fork support 8 inch? Cause i cant find any information on my fork
Originally Posted by Drunken Chicken
Boom, dead on. That looks so fun, slightly technical but you could pick up sooo much speed! Oh, and what's the fork on the Enduro posted here?
The fork on the Enduro is a 2004 Z1 FR SL. It is awesomely stiff and plush. It is much " burlier" than the orginal Fox Talas and the axel to crown height is slightly higher so it slackens the head angle just right for the type of riding I do. Also, the 04 Fox forks are not rated for a 8" Rotor. The 05 Fox's are....
T.J.
Here are a couple more shots from that trip if your interested.
On the way up Jumping Pond Ridge
Looking south on top of Cox Hill
Tequila Joe “Posing”
Last edited by Tequila Joe; 11-24-05 at 12:34 PM.
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130mm
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How heavy are you? I am 240lbs and even down slight downhills the extra stopping power of an 8" rotor will come in very handy. On the big and steeps......8" or nothing! I am getting BB7s with 8" rotors on my soon to be new bike.
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Originally Posted by Tequila Joe
EDIT: If you are seriously considering 8" rotors, be sure to check with your fork manufacturer to be sure it can handle the added forces. Some forks are not rated for 8" rotors (I.e. All Fox <04, most X/C forks...)
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Originally Posted by Expatriate
An 8" rotor with a 9mm QR is asking for trouble. Most manufacturers specify 20mm thru-axles if you want to run an 8" rotor.
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Originally Posted by Caveslave
How heavy are you? I am 240lbs and even down slight downhills the extra stopping power of an 8" rotor will come in very handy. On the big and steeps......8" or nothing! I am getting BB7s with 8" rotors on my soon to be new bike.
T.J.