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Djkaplan
| | Posted on Friday, July 20, 2007 - 03:18 pm: | 
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"In GP racing, they are pouring millions of dollars into these bikes, with mega millions at stake. If ZTL were such a great system, I assure you, egos would be set aside to win races."
With that line of reasoning, what wouldn't a manufacturer copy an entire engine, or chassis or entire motorcycle to win? If egos weren't important in racing... THERE WOULDN'T BE ANY RACING. |
Itchybro
| | Posted on Friday, July 20, 2007 - 04:06 pm: |
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My favorite response was #5. |
Tommy_black_shark
| | Posted on Monday, July 23, 2007 - 08:20 pm: |
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In MotoGP I believe all the bikes are using carbon-carbon brakes. They weight nothing and work great...once they get hot. Brakes that need to be "warmed up" are not your best bet for street motorcycles. |
Buellshyter
| | Posted on Monday, July 23, 2007 - 09:00 pm: |
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I do believe McWilliams has been quoted as saying the ZTL2 is the best brake system he's used outside of MotoGP. |
07xb12scg
| | Posted on Monday, July 23, 2007 - 11:46 pm: |
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With that line of reasoning, what wouldn't a manufacturer copy an entire engine, or chassis or entire motorcycle to win? If egos weren't important in racing... THERE WOULDN'T BE ANY RACING.
IMO no. Manufacturers try to make bikes that are better than the competitors' bikes not equal. If ZTL is substantially better than a dual disc setup do you not think at least one manufacturer would use it in GP racing? |
Trojan
| | Posted on Tuesday, July 24, 2007 - 05:00 am: |
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Just a question?
I first saw perimeter front brakes (ZTL) on road racers back in the 60's. If they are so superior in so many ways, why are the fastest bikes in the world (GP road racers) not using them?
Just curious
A subject very close to my heart 
Perimeter brakes were tried in both 125GP and WSB during the last few years. Both disciplines rejected them simply because they were no better than current systems available. I am eagerly awaiting the 1125R so I can try the ZTL2 for myself, but I have plenty of experience of brake fade and brake pad disintegration on the stock ZTL1 when pushed hard.
ZTL may have plenty of benefits in reducng unsprung weight etc, but if it doesn't stop the bike as well and as consistently as twin discs then it isn't going to catch on with other manufacturers.
I had a phone call only yesterday from a bike journalist complaining that his brakes faded to nothing after just 5 laps of Cadwell Park circuit, and asking if there was anything he could do about it.
Why is it that the factory seem to think this problem doesn't exist, or that if we bring the subject up we are 'trolling' or criticising Buell in some way?
The stock answer that 'Jeremy McWilliams has been quoted as saying the ZTL2 is the best brake system he's used outside of MotoGP' is not an answer to the problems of ZTL1 and is not relevant to the problems on the stock brake. |
Kowpow225
| | Posted on Tuesday, July 24, 2007 - 03:59 pm: |
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Brake fade is, essentially, caused by overheated brake fluid correct?
Maybe another leap for the ZTL setup may be an improved caliper with increased heat dissipating abilities? (like the 8 piston caliper on the 1125r) |
Skully
| | Posted on Tuesday, July 24, 2007 - 05:42 pm: |
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As stated before, the pads themselves can make a HUGE difference. |
Mr_gto
| | Posted on Tuesday, July 24, 2007 - 11:04 pm: |
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I a 230lb rider who goes to the dragon 3 or 4 times a week and ride pretty hard, i dont notice that much brake fade. O and i have worn out a set of pads in less than 3k fade free. |
Blake
| | Posted on Wednesday, July 25, 2007 - 12:57 am: |
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"I had a phone call only yesterday from a bike journalist complaining that his brakes faded to nothing after just 5 laps of Cadwell Park circuit, and asking if there was anything he could do about it."
New fluid, good bleeding, new pads. |
Blake
| | Posted on Wednesday, July 25, 2007 - 12:59 am: |
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If that fails to cure the issue, then new ZTL-2 caliper.
How many racing machines use the OEM front brake? |
Trojan
| | Posted on Wednesday, July 25, 2007 - 08:59 am: |
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New fluid, good bleeding, new pads
I have sent him some new SBS sintered race pads, brake cleaner and setup advice, so hopefully this will help. This is a long term test bike that the magazine have for the year, and so far every rider that has tried it has complained about the brakes.
How many racing machines use the OEM front brake?
Actually more than you would think. Maybe not at WSB/GP level, but have a look around any club paddock and you'll see that most of the Superbikes have stock calipers fitted. We know from experience that stock R1 brakes are superb and need very little done to make them race ready (just race pads).
The calipers fitted to the latest generation of 600/1000 sports bikes are as good as full on WSB brakes were 2 years ago. |
Neb25
| | Posted on Wednesday, July 25, 2007 - 09:56 am: |
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Some racing classes do not allow replacing the stock caliper. I have been able to eliminate fade while racing by using any number of the sintered pads out there like, Braking, Nissin 804, EBC GAF in combination with Motul racing brake fluid. The performance is great and the only problem now is that these pads will not make it through a whole race weekend.
Henry Duga of Buell Racing got me the new thicker disk that the XBRR uses and that is an upgrade that I really recommend. I have talked to a few racers that say adding the radial master cylinder also increases performance but it is not allowed in some classes.
Talking with a couple of racers who race the XBRR said that the 8 piston with the radial master cylinder is awesome and pad life is similar to the other sportbikes. |
Sloppy
| | Posted on Wednesday, July 25, 2007 - 01:57 pm: |
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I can vouch for Motul as well. I lost my brakes on my Honda Motard and nearly sent it into the haybales (thank goodness for being able to do the sideways slide!). It had FRESH DOT 4 Penzoil Syn. Brake fluid at the time.
The pit next to me had Motul that they let me use and I never had another brake fade problem since...
It doesn't matter what brake brand you have -- you need to put in the right fluid and pads for what you're going to use it for... |
Dtx
| | Posted on Wednesday, July 25, 2007 - 10:03 pm: |
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I have had 3 track days using the Nissin 804's and have not experienced any fade. To me, they are worth the $80. I also make sure my brakes are properly bled. My brake lever is very firm.
(Message edited by dtx on July 25, 2007) |
M1combat
| | Posted on Thursday, July 26, 2007 - 01:27 am: |
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"stock R1 brakes are superb and need very little done to make them race ready (just race pads). "
They come with steel braided lines? I haven't looked myself so I don't know... |
L_je
| | Posted on Thursday, July 26, 2007 - 02:17 am: |
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When What's-His-Name first published that stuff in Motorcyclist:
(1) I went downstairs and took measurements on both my Buell and Ducati, and concluded that the rotational inertia of the two brake systems were withing 10% [the XB being 10% higher than the Multistrada]
(2) Went on a spirited ride, and upon stopping, I was amazed (but not surprised) that you could firmly press your finger against the rotor mounting bolts without burning them...this convinced me that no meaningful heat is transfered into the wheel from the rotor (another one of What's-His-Name's assertions).
Brake Fade:
Previously, I did not write a program that would calculate rotor temps for the ZTL vs Conventional Dual Rotor designs. However, this time I will get off of my lazy ass and write a program that takes a first hack at this trade.
"Brake Fade" could be the result of
[1] pads exceeding their temp limits
[2] the DOT 4 temps causing a measurable change in bulk modulus
[3] improper DOT 4 bleeding
[4] feel free to add more stuff on your own
My bets are on #1 and #3. Again, getting a good 1st hack at rotor temps is a good start.
Somebody could save me a lot of trouble by taking these two different systems out on a test ride, and then measuring the rotor temps with a thermocouple [no IR devises, please]. I'm not going to do this because my wife is too lazy to ride her Duc with me, and if she realized I was using her Duc for a science experiment, she'd be pissed.
Oh, and I'm not even going to bother trying to figure out what What's-His-Name is, because he didn't even bother to break out a tape measure and get some facts before he cashed the check for writing that blurb published in Motorcyclist.
And, Bill, I think I still owe you a pizza for trying to measure rotor temps the first time all of this came up; can you, or whomever I owe the pizza to, send me a PM? |
Reepicheep
| | Posted on Thursday, July 26, 2007 - 10:47 am: |
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That was me, but I used an IR thermometer, so I am not sure that counts, so maybe a $3 frozen pizza . And I am on a low carb diet right now... so I won't even eat the crust.
One note in looking at temperatures to measure heat flow (which you no doubt now but want to be sure to account for)...
X amount of thermal energy in a little heat sink will make that little heat sink really hot. The same amount of energy in a big heat sink will make that big heat sink barely any warmer. Put a soldering iron on a penny for 5 minutes then grab it, and compare that to putting the soldering iron on an anvil for 5 minutes then grab that.
Thats not to say your conclusion was right or wrong...
I agree with your brake fade conclusion... the rotors were getting crazy hot, but steel can do that. I think the stock pads were the "weak link" in the system... (weak only in the sense that I could overwhelm it with deliberate abuse). And I know I could use a good bleeding on those brakes again anyway, it's only been done once in 20k miles.
And let it be said, that while I could feel them fading, even in the midst of bluing rotors, smoking pads, and stinking smells, the brakes were still effective in stopping the bike. |
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