what is the difference between radial and standard brakes?

As stated in the title I would like to know what the benifit of radial brakes are and why they seem to be the preference. What differences do they have mechanicly from standard hydrolic brakes?

Shamelessly stolen from another site.


Around 2003, motorbikes started to hit the showrooms with a new feature - radial brakes. The magazines and testers will all tell you that radial brakes make the bike stop quicker. Not true - they have nothing to do with stopping power and everything to do with the design of the front forks of the bike. More and more bikes are coming out with upside-down forks. ie. instead of the fat canister part of the fork being at the bottom of the assembly, it's at the top. This means that the fork pistons are now the part of the suspension with the wheel attached to them. It also means that it's impossible to put a stiffening fork brace down there now because the brace would need to move with the wheel, and the length of the fork pistons precludes that.


The stiffness of the front end is now entirely dependent on the size of the front axle. Bigger axle = stiffer front end. A side-effect of this design was that traditionally-mounted brake calipers could cause a lot of vibration in the steering because of flex between the wheel (with the brake disc bolted to it), and the fork leg (with the caliper). The slight tolerance allowed by floating brake rotors couldn't compensate for the amount of flexing in the forks. To reduce the brake-induced fork vibration, the brake calipers were moved around the rotors slightly so that they fell into the front-rear alignment of the wheel axle. There's less lateral flex at that point, which means less or no vibration. The caliper mounts were changed too. Traditional calipers bolt on to the forks with bolts going through them at 90� to the face of the brake rotor. With radial calipers, the bolts are aligned parallel to the brake rotor - effectively also in the front-rear alignment of the wheel. This design is a trickle-down technology from superbike racing where a radial caliper mount allows the racing teams to use different diameters of brake rotor by simply adding spacers between the caliper and the mounting bracket.
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radialcalipers.jpg

Took the words right out of my mouth! :fing02:

Radial brake calipers are hydraulic too, and in almost every respect they operate on exactly the same principles as conventional brake calipers.

What's different is how they mount.

Conventional calipers are bolted to the forks/brackets with bolts that run east/west in relation to the rotor, which is oriented north/south.

Radial calipers are mounted with bolts that also are oriented in the north/south plane. The idea is that when the pads grab the rotors, the caliper/fork lower assembly has that much more strength and stiffness because the forces involved are all acting in the north/south plane... the radial calipers are more positively located when comparred to conventional calipers which experience shear forces through the mounting bolts in the n/s plane and potentially have flex issues.

I think that for street riding it's probably a moot point; on the track, you probably want the stiffest braking system you can get. Which is where radials originated, of course.

Why is it advantageous on the street? Well, it is simply because radial caliper systems carry the latest in braking technology from a material, assembly and design perspective. If all of that current tech was applied to a conventional caliper system it would probably brake to 99.9% of the efficiency of the radial caliper system.

But most importantly, radial calipers are cool, man, and although we just got sucked into paying more for much the same - like in everything else these days - at least we're cool :fing02:

Edit: that's a good explanation! Have not seen that take on radials before, makes good sense.

Great Explanation Earthshake... :fing02: ...even if You did "Steal it"....... :fing02:

Radials can also be produced in a true mono-block design which can be smaller and lighter for the same or more power as conventional.

Ironically due to current supply and demand on the used market, radials can many times be found cheaper than more popular conventional calipers.

VFR1200's






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I've reached a new state of Enlightenment...again. :fing02:

Good to know. I was always wondering and too lazy to look it up. :fing02:

Excellent explanation. I learn something everytime I visit this site. :biggrin:

Who uses Brakes? :biggrin:

Damn things just slow you down! :biggrin:

Who uses Brakes? :biggrin:

Damn things just slow you down! :biggrin:

Not me, I just make sure I never get fast enough to need em'....... http://www.vfrdiscus...tyle_emoticons/default/+1.gif

I knew I'd learn something useful today!

Who uses Brakes? :biggrin:

Damn things just slow you down! :biggrin:

Hey BR. Brakes are better for stopping than your feet.

How are you healing up?

Why is it advantageous on the street? Well, it is simply because radial caliper systems carry the latest in braking technology from a material, assembly and design perspective. If all of that current tech was applied to a conventional caliper system it would probably brake to 99.9% of the efficiency of the radial caliper system.

I completely agree. A person climbs aboard some new zing-bling hotrod uber-bike that has a decade of design and material science improvements over their existing bike....and it just happens to have radial brakes....and they're soon raving about the radials as the next big thing. :idea3:

To this day, the beefy, 10 year old RC51 conventional brakes are still considered as good (feel and stopping power) as any other production-based brake out there, radial or otherwise. :fing02:

So....we could talk about the radial master cylinder. Conventional M/Cs generate just as much fluid pressure as a radial M/C. But because the radial cylinder/piston is mounted such that it is north-south just like the lever/finger movement (instead of being converted to east-west movement by the pivot point), there is better "feel". Again, you're on a newer, cooler bike with better brake lines and other groovy stuff, so this improved "feel" could be a part of that overall improvement, just like with radial brakes. There is talk that a radial M/C has less distortion of the whole cylinder/lever housing under hard braking, and this might contribute to the better feel, too. But again....on the street these improvements are soooooo negligible.

Better to spend your time with high-speed braking practice that in the garage converting your VFR to blingy radial stuff.

Thoughts?

Always wondered about that?!? I try to learn something new every day... great explanations! Thanks for continuing my education! :fing02:

man, time marches on. I was a god on the track(in my own mind), on bias ply tyres. I remember people oogling at my front dunlop radial at the track. (like I knew, or could tell the difference).

Im glad I wasn't the only one who did not know :idea3: Thank you for clearing this up and giving me a better understanding :fing02:

Good pads and properly bled lines are more important than a radial mount.

Stock to stock ridden hard at the racetrack the radial brakes on my 04 CBR1000RR didn't hold a candle to the "traditional" brakes on a '02 RC51 that I tried out.

VFR1200's






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I keep wondering how the LBS on the 7th gen works now with the radial mount calipers since the earlier models relied on the caliper's pivoting mount to charge the secondary MC to engage the rear caliper.

I keep wondering how the LBS on the 7th gen works now with the radial mount calipers since the earlier models relied on the caliper's pivoting mount to charge the secondary MC to engage the rear caliper.

via the flow of electrons like almost everything else on the newer Honda's. There was a good video on the new Combined Braking System someplace.

[video: https://youtube.com/embed/KbXRzLioXdg?html5=1&fs=1] 3 parts.

The difference between radial brake calipers and the old blade mounts
is a step forward like fuel injection was to carbs and like flip forks
are to the old conventual forks... a leap in technology that once
your try it there is no going back...

Mr.RC45 stock blade Nissins with home made mounts to fit 320mm Ferodo
6 button Super light cast iron rotors..

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Mr.RC45 Brembo billet radial calipers with home made magnesium mounts
to Brake Tech 320mm Ceramic Matrix Composite rotors

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Better to spend your time with high-speed braking practice that in the garage converting your VFR to blingy radial stuff.

Thoughts?

But its so much fun, what would I do if I just bought a bike that had nothing for me to replace?

Great info... :wheel:

The difference between radial brake calipers and the old blade mounts
is a step forward like fuel injection was to carbs and like flip forks
are to the old conventual forks... a leap in technology that once
your try it there is no going back...

Mr.RC45 stock blade Nissins with home made mounts to fit 320mm Ferodo
6 button Super light cast iron rotors..

Mr.RC45 Brembo billet radial calipers with home made magnesium mounts
to Brake Tech 320mm Ceramic Matrix Composite rotors

OK, enough of that, BLS, you're making those of us who don't live in a machine shop jealous!

At what speed do those carbon jobbies become effective? They don't have enough of a friction co-efficient to be useful on the street, right?

o, and always, fricken sweet :fing02:

So....we could talk about the radial master cylinder. Conventional M/Cs generate just as much fluid pressure as a radial M/C. But because the radial cylinder/piston is mounted such that it is north-south just like the lever/finger movement (instead of being converted to east-west movement by the pivot point), there is better "feel". Again, you're on a newer, cooler bike with better brake lines and other groovy stuff, so this improved "feel" could be a part of that overall improvement, just like with radial brakes. There is talk that a radial M/C has less distortion of the whole cylinder/lever housing under hard braking, and this might contribute to the better feel, too. But again....on the street these improvements are soooooo negligible.

I think radial M/C's have a simple mechanical advantage over standard type m/c's and through that higher efficiency provide More braking power for any given lever pressure vs a standard m/c of the same size.
I've added one to every track bike I've owned that didn't come with one, to improve feel and power. :fing02:

Because I ride the PACE I probably won't add one to the street Vtec unless I do a front end swap some day. http://www.vfrdiscus...tyle_emoticons/default/wink.gif

For street riding....... one just looks much kewhler than the other..... :fing02:

Beck
95 VFR

[

OK, enough of that, BLS, you're making those of us who don't live in a machine shop jealous!

At what speed do those carbon jobbies become effective? They don't have enough of a friction co-efficient to be useful on the street, right?

o, and always, fricken sweet :fing02:

Owning a machine shop is minimum tools for living with an RC45 because
no aftermarket company antes up for such low number bikes...

They are not carbon jobbies... Ceramic Matrix Composite bite right out
of the gate so they are perfect for the street and track... they offer
the same co-efficient as a good set of cast iron rotors...


Quote my good friend Jeff Gehrs of Brake Tech USA

"Brake Tech USA is very pleased to announce the release of the long
awaited, ultra-advanced technology Ceramic Matrix Composite brake
rotors for the Motorcycle Industry. The AXIS/StarBlade™ is the new and
updated MKII version incorporating now de-classified Stealth Bomber
Aircraft technology manufactured by Starfire Systems, this
revolutionary material will change the way both top-level race teams
and enthusiasts alike view their braking systems. The performance
parameters in-total make all previous materials and systems dated by
comparison, including the vaunted Carbon/carbon brakes. Designed to
perform brilliantly with OEM calipers as well as the Billet GP
race-spec versions. This all-new composite material offers the best
features of premium iron rotors with the incredible lightweight of
carbon, and none of the Carbon/carbon foibles!"

Performance features include:

* Not thermally sensitive (will work great on the street)
* Ultra broad torque curve across a very wide thermal range
* Much longer lasting than Carbon / carbon
* Much less expensive than Carbon / carbon
* Great wet weather performance - unlike Carbon / carbon [not hygroscopic]
* Terrific feel and feedback at the lever
* Strong braking performance? We mean, Really strong: +.6 mu average friction with special Ferodo
Racing brake pads


How it all adds up:

Stock Honda 310mm stainless steel 3 lbs 4 oz

Ferodo 320mm Ductle Iron 2 lb 8 oz

Ceramic Matrix Composite 1 lb 7 oz

I keep wondering how the LBS on the 7th gen works now with the radial mount calipers since the earlier models relied on the caliper's pivoting mount to charge the secondary MC to engage the rear caliper.

via the flow of electrons like almost everything else on the newer Honda's. There was a good video on the new Combined Braking System someplace.

[video: https://youtube.com/embed/KbXRzLioXdg?html5=1&fs=1] 3 parts.

That kinda freaks me out, and I'm no technophobe. I guess I prefer my foot and hand to directly apply the hydraulic pressure, rather than being turned into a data point for the computer to measure and then apply the brakes for me.