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Guest friz

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...not to hijack your thread, but on that note, I wish someone would come out with a semi-floating rear rotor for our bikes.

 

 

I've seen the wave rotors on some Sports, so I know they make ones that fit. Just find the correct diameter rotors, made for our Brembo(Guzzi, Ducati) applications, and it should be fine.

 

A quick "Google" for "wave rotor guzzi" yields the following:

 

http://www.gforcecycles.com/Merchant2/merc...ry_Code=400.400

 

Give them a call, they have a listing for Guzzi "Daytona, Sport1100, and Centauro" which I believe should be the correct size(double-check).

 

al

 

 

P.S.

 

DANG, those things are expensive, $270 EACH! :o Unless I was racing, one would be hard pressed to prove to me that they deliver over $500 of increased braking performance, plus no offense, but I think their kinda ugly :P

 

For ~$500, if one wants really better braking, look up a thread from Paul regarding upgrading the whole front brake system(calipers and all) to Brembo's next better setup for that price :thumbsup:

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Ok, so I've been wondering since I first saw these things, what on earth is the advantage?

 

"As with all BRAKING rotors, the wave rotor allows a high coefficient of friction while minimizing the amount of pad wear"

 

That's a worrying claim. High coefficient of friction means either more pad wear or more disc wear. I refuse to believe they've rescinded the laws of physics, so it must mean that the rotors themselves wear down faster.

 

"The wave concept is the efficiency in which it utilizes all the brake pads surface evenly, the elimination of lightening holes (for added strength) and the ability to expand and contract as it heats up without warping the disc."

 

First of all, that's not really English. Second of all, the thing is composed of holes; what are they talking about? Finally, I'll have to take their word that it can heat up without warping. That seems like the most likely claim so far.

 

And really, stopping power of a brake caliper and disc system is probably best expressed by pressure * coefficient of friction * surface area. Since pressure isn't changing (same calipers and hydraulics), and coefficient of friction of the pads isn't changing (they claim "normal pads" can be used), and surface area is going down, the disc must be made of something unusual, which raises the coefficient of friction with normal brake pads. By that reasoning, the "wave" shape is nothing more than a trick to get less surface area in contact with the pads to keep us from tossing ourselves over the handlebars.

 

"Offers maximum stopping power by the disk using all the pads of the surface"

 

Although those words are all English, they're not arranged in a way that makes any sense. In any case, although the pads will be equally worn because the wave shape still hits the high and low points of the normal disc, they can't ever contact as much surface area at once, since there's so much missing.

 

Am I wrong? (NB: "all the racers use them" is not a valid argument in this case -- gear that's appropriate for racing is generally not appropriate for street use. I don't want to be replacing my $550 set of brake rotors every 6 months.) I'd love to know the actual, non-marketroid advantages of these things.

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iAn, sourcing shoun't be aproblem. Size is the same as most modern duc's( monster/916 etc) Not the 748r or 999.

In the usa you also have disks from galfer

http://www.hardracing.com/Brakes/Galfer.htm

The easyest way of upgradinng braking is

: better pads

The new hit around here are "Performance Friction" pads.

I upgraded my disks to the narrower track brembo's from a 748. I paid not much more for them ojn ebay as I got for the original disks. Then I added the newer p4 brembo's that have 4 pads in each caliper.

But haven't used it by now, has to wait.

And the other upgrade you can make is a radial master cylinder. Used on ebay 200$ for a brembo. Some people only do that with pad's.

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That are fine looking calipers, but they don't make em with 65mm mounting distance. And I hate to put some adapter in between. Did you see my rear pvm caliper? On my v12 page.

Master cilinder looks a bit over engineerd. Thta's why they have the harley folks as customers? If cost is no object i vote for pvm's master cilinder, 3 way adjustable ratio. One day...

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ISR is a small manufacturer,

more like a workshop rather than a factory.

I am sure you can order thing to exact specification,

I will cost an arm and a leg but it is doable. :luigi:

(even the normal USR stuff is not cheap, neither is PVM stuff)

 

Many scandinavian race teams swear by ISR brakes.

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Paul,

 

I'd be interested to hear the how and why you went with the "wave rotor" and the PVM caliper out back.

 

It seems like the stock Brembo caliper and rotor are pretty good(other than the rotor/caliper groan issue of course)... ??

 

Just curious :)

 

al

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Al,

I have ordered a PVM rearwheel, so with the new wheel, began the thinking about the rear brake. I don't use the brake, but it should be there, and working. The disk is only 190mm against the 280mm from the v11. That's real lightweight. It's a scooter front disk. Then after I decided on the disk, I went looking for a caliper, the stock one doen't fit here. So after looking at the posibilities, I bought a one size smaller version of the brembo, 30mm pistons instead 32mm. And designed a mounting thing for the caliper. And then Ebay came.... I had seen the PVM 4pot caliper already, but at 500+ euro way to expensive. But then it was on ebay, and now it's mine :food::food: . It's new unused. It's milled out of one piece of billet. Beautifull made. I'm now designing a new mounting thing for it. And I can use a program that lets you apply forces on the piece, so you see where you can take off material, or have to make it thicker. Fun playing.

But I wait until I get the wheel with (letting it) make it from billet.

See attached picture what sort of output such a program gives.

brakestudy.jpg

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I thought the advantage of the "wave rotor" was supposed to be in heat dissipation due to the greater surface area?? I really have no idea, but that was the marketing hoopla I thought I ran across at one point :huh2:

 

I still think they are ugly :lol:

 

al

Al,

 

The thinking behind the wave rotor is that the surface area of the rotor edge is increased by adding dips or valleys on the rotors edge. More surface area equals more cooling. If you measure the circumference of the wave rotor including the valleys and compare it to a stock 320 mm. rotor, the wave design will have a higher measurement, thus having more surface area. By making it a wave, there is also more material that is removed so the rotor also comes out lighter. Many racers say that they can feel the difference between the weights of the rotors.

I have tried the Galfer Wave rotors and while I could not feel the difference in braking or even having the lighter rotors, there is some coolness factor that the rotors have. The coolness factor did not last to long. The rotors have a fast wear rate and mine were junk by the time I had 2500 miles on them. Very bad pulsation which made smooth braking a bitch. I talked to Galfer and he wanted the rotor back to take measurements. I sent them back and they could not find anything wrong with them. Just to make me happy, they installed looser fitting rotor buttons to make the rotors float more. I received the rotors back and reinstalled them.. A quick ride down the street and the brake pulsation was still there. I called Galfer back and asked him how he measured the rotors. He said that they were taken apart and layed on a flat surface and measured with a dial indicator. My reply was "you are only measuring one side" his reply was that they had been making rotors for a while and knew what they were doing. My reply was if you use a micrometer and measure the thickness difference around the rotor, you will find why I have a bad pulsation. Well, after a long conversation, Galfer agreed to refund 100 % of my money back . All I can say is Galfer backs up their product, I wish more companies would do the same.

 

Mike

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So, did the Galfer Wave seem to be made of an odd material, Mike? High-carbon steel or anything weird like that? I'm still trying to understand how they can accomplish "higher coefficient of friction" with less surface area hitting the pads. The fact that your waves were toast after 2500 miles suggests that the disc material is something that wears down really fast, which would make sense.

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So, did the Galfer Wave seem to be made of an odd material, Mike? High-carbon steel or anything weird like that? I'm still trying to understand how they can accomplish "higher coefficient of friction" with less surface area hitting the pads. The fact that your waves were toast after 2500 miles suggests that the disc material is something that wears down really fast, which would make sense.

I have had Low carbon steel rotors on my 1100 sport for well over 50 000 km's. These are of conventional design and not the wave type. The have lasted fairly well however I don not use sintered metal pads these will eat any disk material. The Wave shape advantge seems to be more applicable int he dirt where the large holes allow the caliper to clear the disk of deberies a lot faster. There is a definate lack of wave rotors in use int he road racing secene. My rotors are made buy braking and at the time were not considered quiet as good as the cast iron bembo's but were two thirds the price.

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So, did the Galfer Wave seem to be made of an odd material, Mike?  High-carbon steel or anything weird like that?  I'm still trying to understand how they can accomplish "higher coefficient of friction" with less surface area hitting the pads.  The fact that your waves were toast after 2500 miles suggests that the disc material is something that wears down really fast, which would make sense.

The Galfer rotors were stainless steel, I don't remember what the number of the stainless they were using. I used the recommended brake pads which were the HH pads that tend to be rather hard on rotors.

 

Mike

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