1 rotor VS 2 rotors

[Mystic]

this is something i always see pop up on other boards (mostly car forums) ive been seeing some bikes and they are missing one of the front rotors and calipers ....bascially saying "hey check out my chrome wheel" well i think it would kill the stopping of the bike at high speeds as your taking out something thats stopping the bike ....what is everyones take on this ??has there ever been a test with someone doing this ??? maybe im wrong but everyone loves to argue saying it doesnt effect anything

[Pittenger5]

Superbike its for looks
LW bikes 1 rotor is more than enough stopping, 2 is just weight

[Jim]

since you use 90% of your front brakes on a sport bike, i couldnt imagine taking out 1/2 of my stopping power.

[GixerJockey]

since you use 90% of your front brakes on a sport bike, i couldnt imagine taking out 1/2 of my stopping power.

Why? You're slow ass is only using 1/4 of it anyway...

[Jim]

noel, this thread is for street riding. something you wouldnt know anything about this year

[GixerJockey]

noel, this thread is for street riding. something you wouldnt know anything about this year

That is true.

Maybe you'll understand next season if you survive your rookie race.

[Kitt]

That is true.

Maybe you'll understand next season if you survive your rookie race.

jim's a bench racer... it will be weird if he shows up for the rookie race.


oh - and noel... get out of this thread for real. you're gsxr doesn't require rotors for pushing it around in the garage.

[e30addict]

since you use 90% of your front brakes on a sport bike, i couldnt imagine taking out 1/2 of my stopping power.

you're "stopping power" is really limited by the grip tire has, not how many rotors. The rotors are the heat sinks and help you stop over and over again; but the fast folks on here already know that. Let the flaming continue.....

[bigred875]

Wirelessly posted (bb tour: BlackBerry9630/4.7.1.40 Profile/MIDP-2.0 Configuration/CLDC-1.1 VendorID/105)

It is for looks but they will say it is to save weight...rotating mass



Fwiw i had a 98 gsxr 600 that was missing a a rotor but had a ss line and ebc hh...it stopped fine on the street

[Trouble]

I listened to the cool kids halfway through this year and removed one caliper and rotor from my front. I don't miss the second rotor at all. Of course I'm slow and have a 954RR front end on a Hawk so I'm stopping about half the mass that the origional brakes were designed for. Maybe I'm not such a good example after all...

[Mad Max]

you're "stopping power" is really limited by the grip tire has, not how many rotors. The rotors are the heat sinks and help you stop over and over again; but the fast folks on here already know that. Let the flaming continue.....

I agree to a certain point but on dry pavement, in a straight line almost any tire on a sportbike will have enough grip to flip the bike. I agree that the rotors are a heat sink and that the added mass and surface area of the second rotor is what allows for serious repeated braking (e.g. road-racing).

By removing one caliper and rotor you will reduce the braking force that you can apply at the wheel. You could overcome this by using a M/C with a smaller bore or a different leverage ratio. You have to realize though that what ever you do you will effectively be doubling the pressure in the brake lines to obtain the same braking force as you would with two rotors. I wouldn't be too concerned by this because I would imagine that the safety factor for the brake lines is based on someone with a strong grip over-squeezing the brake lever (probably 3-4 times what is needed to flip the bike) and calculating the line pressure from that. If you change your M/C for a smaller bore you might want to keep the big fisted guys from using your brake lever as a grip strength exercise

A solution to mitigate the potential line pressure problem with the stock M/C would be a larger caliper with either more pots or larger pots, the goal just being to increase pot surface area. This will also reduce the braking effort required at the lever. Higher mu brake pads will do the same.

Interestingly enough, if you knew that you were supposed to clean the rotor/wheel interface on a car setup before putting the wheel on you might have thought it was to make sure the wheel sits flat. While that is one reason, another is to make sure that you get good surface mating to increase the amount of heat that can be transfered to the wheel from the rotor. Aluminum is a great conductor of heat and can be integral to keeping your car brakes cool.

[OreoGaborio]

since you use 90% of your front brakes on a sport bike, i couldnt imagine taking out 1/2 of my stopping power.

It has more to do with brake cooling & fade reduction than braking power.

[spydah]

Not to mention redundancy. God forbid your caliper bolt comes loose going into turn 1 with only 1 caliper. We all know its not unheard of. Your rear brake alone is not going to do anything other than high/low side you.

[Paul_E_D]

No, spydah, in that case a second rotor doesn't provide redundancy. If one fails, both fail due to reduced line pressure.

One rotor has the same stopping power as two, however like everyone says, two rotors can cool twice as fast, thus resisting fade in racing. On the street no one brakes often enough to induce fade, so it has no affect on performance

[TTD]

I love how if you stick around long enough... every thread will come back.




The way it was explained to me many moons ago (by our own Chris Bruno ) was as referenced above.

In other words, if you have two rotors, they are being squeezed with half the force than that setup with one rotor... so you don't get more stopping power with two rotors.

As Paul and others said though, there are potentially other benefits with cooling and possibly rotor longevity?

[RandyO]

I'd rather have a perimeter brake on one side in front than 2 standard brakes

[Fitz]

All street talk aside, I was comfortable running one rotor on the track until I started seeing consistent 1:26's. At that point I started getting some brake fade in T3 and alot of brake fade coming into the bowl. Added the second rotor and caliper and now I have more brake capacity than I know what to do with.

One thing I did like with the single caliper/rotor setup was the ultra low travel brake lever. Once I added the second caliper/rotor back in, I displaced 100% more fluid due to adding another 6 pistons. This increased lever travel.

Fitz

[RandyO]

One thing I did like with the single caliper/rotor setup was the ultra low travel brake lever. Once I added the second caliper/rotor back in, I displaced 100% more fluid due to adding another 6 pistons. This increased lever travel.

Fitz

you didn't replace your master cylinder as well?

[brady]

One rotor has the same stopping power as two, however like everyone says, two rotors can cool twice as fast, thus resisting fade in racing.

One thing I did like with the single caliper/rotor setup was the ultra low travel brake lever. Once I added the second caliper/rotor back in, I displaced 100% more fluid due to adding another 6 pistons. This increased lever travel.

Using two rotors should also give better modulation and feel at the limit, shouldn't it?

[SVRACER01]

you didn't replace your master cylinder as well?

he replaced it with a 86 F250

[Fitz]

you didn't replace your master cylinder as well?

My apologies I should clarify. The bike is a 1st gen SV650 with a TLR1000 front end; TLR master; 6 piston calipers, and TLR 320mm rotors. It was my first year racing and my laptimes were in the 1:33's. Frankly the bike had much more heat capacity than I needed. I've always had ultra low travel brake pedals on my race cars and even after multiple bleeds was unhappy with the amount of travel with two calipers. Removing one halved the travel.

Using two rotors should also give better modulation and feel at the limit, shouldn't it?

I guess. I've never washed the front end so I can't really say I'm at or near the limit. I routinely pick up the rear tire in T3 but that doesn't mean I'm at or near the traction limit there either.

he replaced it with a 86 F250

Just the opposite. The '86 F250 decided to replace my femur with a 16" titanium rod and 3 Ti screws. I would have preferred a Brembo master cylinder for the bike.. maybe something in a 19x20 flavor...

Fitz

[spydah]

No, spydah, in that case a second rotor doesn't provide redundancy. If one fails, both fail due to reduced line pressure.

One rotor has the same stopping power as two, however like everyone says, two rotors can cool twice as fast, thus resisting fade in racing. On the street no one brakes often enough to induce fade, so it has no affect on performance

sure, if your taking reduced line pressure. I was talking about the caliper coming off. So long as the line is in tact you could still stop once the pads touch eachother. Not sure how practical it is and I hope nobody finds out.

On thing I did find this season while tooling around with xbootlickx's 1125R is that some thing happened with it while I was riding and when he went back out on the bike after my romp there was no pressure for the first couple of squeezes. Possibly to do with the heating of a single caliper?

[brady]

So long as the line is in tact you could still stop once the pads touch eachother. Not sure how practical it is and I hope nobody finds out.

Someone did find out at a trackday, doesn't work well at all if there's not an obvious bail-out like in T1.

[Paul_E_D]

Ya, after three empty grabs at the brakes, you're busy dealing with other problems...

[Pittenger5]

Try losing all braking power in t9. When you have 1 caliper. Every lap.

Good times.