8" Rotor For Better Braking Power?

What he (Slack) said. Tom
Slack wrote:


It's all about torque. Try loosening a BB with a wrench that has 12"
handle, then try it with a 24" handle
much easier because you have greater (longer) torque arm.

8" vs 6" rotor is similar exercise, only difference is now you have a
spinning mass. Heat build up and fading are largely due to rotor design
and brake pad material, but the type and quality of brake fluid are also
very important. If your friend didn't notice a diff., then he's either a
corpse, setup the brakes wrong or is using really-really crappy brakes.

http://www.hayesdiscbrake.com/hayesu_product1.shtml
--
Slack

A single crown fork will be fine, unless it's made out of noodles.

What you need to consider is the dropout. A standard 9mm dropout can have
excessive force applied to the axle, whereas a 20mm axle will be fine. Most
bike/fork manufacturers will state that 8" rotors are not a good idea on a
fork with standard dropouts. Marzocchi made a triple clamp fork with
standard dropouts, and with a month I saw 3 that broke the axle when an 8"
rotor was used. On the other hand, I see numerous single crown forks with
8" rotors (I've run the setup myself), and there are no issues.

The advantages of an 8" rotor over a 6" rotor is increased braking power
because of the additional torque, and increased heat dissipation, because of
the larger surface area. The disadvantage is the weight the additional
weight, as well as a rotor that is easier to damage in crash because there's
more rotor to hit something.

"JD" wrote in message
oups.com...
Exactly. An 8" rotor on a single crown fork may be a recipe for
tearing that fork into little bitty fork bits under the right rider.
It's all about physics.

Corvus Corvax wrote:
Ride-A-Lot wrote:

I thought it was that a bigger rotor minimized the fade. No?

Sure. Since the total amount of heat generated is independent of rotor
size, a larger rotor (with better heat dissipation) will fade less, all
else being equal.

That's why I run 26" rotors, also known as V-brakes. ;-)

CC

The rim may be a 26" rotor, but the V-brakes you have are "dual piston
calipers." ;-)

R

Roberto Baggio top posted:
A single crown fork will be fine, unless it's made out of noodles.


Tell us all bags, which manufacturers recommend that you use an 8"
rotor on their single crown forks?

You freerider neophytes crack me up.

JD

JD wrote:

Roberto Baggio top posted:



A single crown fork will be fine, unless it's made out of noodles.



Tell us all bags, which manufacturers recommend that you use an 8" rotor on their single crown forks? You freerider neophytes crack me up. JD


No freerider here, but to be honest, I don't think manufacturers actually recommend a rider run a specific size of rotor....OTOH they often do state a maximum rotor size.  Fox states the maximum rotor I can put on my single crown Float 130 is an 8".

Mike

Michael Halliwell wrote:
JD wrote:
Roberto Baggio top posted:


A single crown fork will be fine, unless it's made out of noodles.




Tell us all bags, which manufacturers recommend that you use an 8"
rotor on their single crown forks?

You freerider neophytes crack me up.

JD


No freerider here, but to be honest, I don't think manufacturers actually recommend a rider run a specific size of rotor....OTOH they often do state a maximum rotor size. Fox states the maximum rotor I can put on my single crown Float 130 is an 8".

The 8"/single-crown combo being no good is a lot of myth. The forces
on the crown from braking are small to begin with, and don't increase
much from a larger rotor.

Someone metnioned physics - I don't see anyone presenting even *one*
set of calculations, or a drawing, or anything, to substantiate the
claim.

But then again, there's a whole newsgroup fully of hot air over bicycle
tech. Probably shouldn't drag it over here...

E.P.

Ed Pirrero wrote:
Michael Halliwell wrote:
JD wrote:
Roberto Baggio top posted:


A single crown fork will be fine, unless it's made out of noodles.




Tell us all bags, which manufacturers recommend that you use an 8"
rotor on their single crown forks?

You freerider neophytes crack me up.

JD


No freerider here, but to be honest, I don't think manufacturers actually recommend a rider run a specific size of rotor....OTOH they often do state a maximum rotor size. Fox states the maximum rotor I can put on my single crown Float 130 is an 8".

The 8"/single-crown combo being no good is a lot of myth. The forces
on the crown from braking are small to begin with, and don't increase
much from a larger rotor.

Someone metnioned physics - I don't see anyone presenting even *one*
set of calculations, or a drawing, or anything, to substantiate the
claim.

But then again, there's a whole newsgroup fully of hot air over bicycle
tech. Probably shouldn't drag it over here...

E.P.


Where's Phil (squid)? Isn't he a materials engineer?

--
o-o-o-o Ride-A-Lot o-o-o-o
www.schnauzers.ws

"Ed Pirrero" wrote in message
ups.com...

Michael Halliwell wrote:
JD wrote:
Roberto Baggio top posted:


A single crown fork will be fine, unless it's made out of noodles.




Tell us all bags, which manufacturers recommend that you use an 8"
rotor on their single crown forks?

You freerider neophytes crack me up.

JD


No freerider here, but to be honest, I don't think manufacturers
actually recommend a rider run a specific size of rotor....OTOH they
often do state a maximum rotor size. Fox states the maximum rotor I can
put on my single crown Float 130 is an 8".

The 8"/single-crown combo being no good is a lot of myth. The forces
on the crown from braking are small to begin with, and don't increase
much from a larger rotor.

Someone metnioned physics - I don't see anyone presenting even *one*
set of calculations, or a drawing, or anything, to substantiate the
claim.

But then again, there's a whole newsgroup fully of hot air over bicycle
tech. Probably shouldn't drag it over here...

E.P.

Same here, my Marzocchi 66RCX2's dont say anything about not recommending an
8". They do state max 8" though...

How do these brake forces compare to doing endo's then?? I would have
thought endos would put more stress on the crown than the brakes...

Cheers Dre

On Thu, 28 Sep 2006 21:08:45 -0700, Dre wrote:

"Ed Pirrero" wrote in message
ups.com...

Michael Halliwell wrote:
JD wrote:
Roberto Baggio top posted:


A single crown fork will be fine, unless it's made out of noodles.




Tell us all bags, which manufacturers recommend that you use an 8"
rotor on their single crown forks?

You freerider neophytes crack me up.

JD


No freerider here, but to be honest, I don't think manufacturers
actually recommend a rider run a specific size of rotor....OTOH they
often do state a maximum rotor size. Fox states the maximum rotor I
can
put on my single crown Float 130 is an 8".

The 8"/single-crown combo being no good is a lot of myth. The forces
on the crown from braking are small to begin with, and don't increase
much from a larger rotor.

Someone metnioned physics - I don't see anyone presenting even *one*
set of calculations, or a drawing, or anything, to substantiate the
claim.

But then again, there's a whole newsgroup fully of hot air over bicycle
tech. Probably shouldn't drag it over here...

E.P.

Same here, my Marzocchi 66RCX2's dont say anything about not
recommending an
8". They do state max 8" though...

How do these brake forces compare to doing endo's then?? I would have
thought endos would put more stress on the crown than the brakes...

Cheers Dre



Biker Fox, is that you?

Is someone recommending endos?
--
Slack

"Slack" wrote in message
newsp.tgmjx3pmntnj34@slacker...
On Thu, 28 Sep 2006 21:08:45 -0700, Dre wrote:

"Ed Pirrero" wrote in message
ups.com...

Michael Halliwell wrote:
JD wrote:
Roberto Baggio top posted:


A single crown fork will be fine, unless it's made out of noodles.




Tell us all bags, which manufacturers recommend that you use an 8"
rotor on their single crown forks?

You freerider neophytes crack me up.

JD


No freerider here, but to be honest, I don't think manufacturers
actually recommend a rider run a specific size of rotor....OTOH they
often do state a maximum rotor size. Fox states the maximum rotor I
can
put on my single crown Float 130 is an 8".

The 8"/single-crown combo being no good is a lot of myth. The forces
on the crown from braking are small to begin with, and don't increase
much from a larger rotor.

Someone metnioned physics - I don't see anyone presenting even *one*
set of calculations, or a drawing, or anything, to substantiate the
claim.

But then again, there's a whole newsgroup fully of hot air over bicycle
tech. Probably shouldn't drag it over here...

E.P.

Same here, my Marzocchi 66RCX2's dont say anything about not
recommending an
8". They do state max 8" though...

How do these brake forces compare to doing endo's then?? I would have
thought endos would put more stress on the crown than the brakes...

Cheers Dre



Biker Fox, is that you?

Is someone recommending endos?
--
Slack

Nope, just me

I'm not recommending anything, personally I prefer wheelies to endos...

So do they put more stress on the crown or what??

Cheers Dre