| Author | Message | ||
     Blake |
Bill (Reepicheep), An IR thermometer will report terribly inaccurate results for shiny, even semi-shiny metal surfaces. Depending upon the level of reflectivity an IR thermometer reads a portion of the temperature of the surroundings being reflected by the smooth metal surface. According to my IR thermometer, my Cyuclone's steaming hot shiny aluminum oil tank never exceeds ambient temperature. I had to open the cap and point it at the oil to get a good reading... 2200F at the track on a hot Texas Summer day. Yeah, I run synthetic.  A little spot of flat black paint would allow the use of the IR thermometer with accurate results. Kinda tough find a spot on the brake rotor to paint though. ![: ]](http://www.badweatherbikers.com/buell/clipart/proud.gif) Good news Matt. For just a bit more investment--you said the Rotors alone cost 300BP, yes, and did you add to that the cost to have your Suzuki forks reworked?--you can now have a system that offers superior braking performance and significantly reduced weight. Win-win-win. | ||
| Blake |
Bill, You might be able to obtain a more accurate temp reading for your rotor if you read the rough surface of its inboard edge, but that is a small target. Fun stuff.  | ||
| Ridrx |
I'm waiting for the ZTL3 -single ceramic rotor, 8 piston caliper w/ cast in heat sinks, a radial master and a magnesium front wheel...drooling now. Optional: 50lb counter weight to keep rear tire earthbound...haha | ||
| Blake |
Spike, I'd have to have been there to take stock of the brake lever action to have a good idea. I'm estimating that there was some air or moisture still inside the system. An XB brake lever should feel rock hard solid. Any hint of sponginess indicates air in the system. That only gets worse as the air heats up with brake use. Also, if the pads were new and you failed to wear them in properly that may have contributed to some fade. But ALL brakes will fade when used vigorously and harshly like on a track. Heat has a very real effect and it is not to improve the quality of a brake system. If your lever went off a little but you still had the ability to apply full braking force, it may be normal fade. If the lever all of a sudden went off to the point of rendering the brakes ineffective, the factors mentioned above likely came into play. The only other possibility I can see is that if you experienced a front end chatter or shake, it may have pushed the pistons back into the caliper, thus leaving you with a lever that required pumping to get the pads re-engaged upon the disk. From Matt's description, it sounds like he is talking about a all out brake failure, not fade. It's happened to me. It was due to moisture in the line. Coming into turn 2 at Oak Hill Raceway and my lever came all the way back to the throttle grip. There was just enough braking action left to keep me from crashing. The moisture got hot enough to vaporize and stay vaporized all the way from turn 8 to turn 2. It's kind of interesting how that works inside a brake system. When you are applying the brakes hard for a prolonged period, they get super hot, but the high pressure inside the system, a thousand or more PSI, prevents any moisture from boiling/vaporizing to any large extent. It's only when you release the brake and the pressure suddenly drops to normal atmospheric (14.7 psi) that the moisture will flash boil into a significant volume of vapor (steam). It's akin to removing the lid from a boiling hot pressure cooker or the cap from your car's hot radiator; what was previously 250 oF liquid water, instantly flashes into steam. Water boils/vaporizes at ever higher temperature as pressure increases. It boils/vaporizes at lower temperatures as pressure decreases. So if you heat up the moisture in your brake line to 230oF while it is under extreme pressure it won't boil until the pressure is removed. So I reverse bled the brake system and replaced the fluid and all was fine. | ||
| Imonabuss |
Matt has a business to run selling parts to replace the "bad" ones on a Buell. Therefore his opinion is certainly as "biased" as Buell, and quite frankly, more likely so. I'm gonna vote for the Buell engineers for having superior knowledge, and being ahead of the world on this. | ||
| Jackelfox |
i think its a bit presumptive to suggest that his opinion is biased due to the possibility of financial gain. i think this is a issue that can have simple differences of opinion. for instance i dont race my XB as such i have no concerns over its race worthiness whatsoever. Similarly i have a very high level of value placed personally on aesthetics and innovation. So for me the ZTL is far and away the best brake given my parameters. | ||
| Jackelfox |
...although i guess plenty of racers feel it fits their parameters as well.. | ||
| Spatten1 |
I'm gonna vote for the Buell engineers for having superior knowledge, and being ahead of the world on this. Reminds me of my Harley riding neighbor who told me: "AMF bought Harley so the Japs could steal our technology" | ||
| Reepicheep |
I grabbed the rotor with my hand, and it felt much cooler then the tire, so while the IR thermometer probably was wrong, it wasn't as hot as the tires. Maybe I ride like a grandma, but the tires *were* at 105 degrees... so maybe I just carry a lot of corner speed (actually, I do ride a fairly booring ride, though I did kill a bird with my boot on that ride last night...) I'll do some wanton rotor abuse on the ride home today (fast stops from highway speeds) and see what kind of peak temperature I can get off the rotor, rims, and tires. I'll try and slap a piece of black electrical tape on a non swept area of the rotor and see if that reads any different as well. But I'm only in it for the Pizza  | ||
| Blake |
Tape no good; it insulate too much. Hands are also not so accurate. Try applying the tender area under your arm to the rotor for optimum thermal sensitivity. plus if it makes a sizzling sound, you know it's really good and hot. Measure caliper temp too. | ||
| L_je |
If I were to "grab my rotor" after I pulled into my garage, I'd be getting a second degree burn. But, I can firmly press my fingers against the mounting bolts without discomfort, so this tells me that the freely mounted rotor transmits a very small fraction of heat into the wheel. ...for an eye-opener, press your finger up against the bolts on a fixed rotor, like the one on the rear wheel...on second thought, don't because you are going to burn your finger. ...I'm only mentioning this because the article in Cycle World was dinging the design because 'it probably transfers a lot of heat into the wheel'. IR gun...yeah, I should have thought about that...Store-bought IR instruments are going to give you bogus temp readings for a specular surface...my bad. Don't bother putting black electrical tape on there either, as you still aren't going to get the right answer. My friend has a multimeter with a pretty good thermocouple set-up, so the next time my wife and I ride over there, I'll get some measurements of the Buell and the Duc side by side. Bill, you are getting your pizza! There's no sense in getting a ticket/killed/third-degree-burns over pizza toppings! And, for the love of God, how many more birds are we going to kill before we stop the ZTL Jihad? I think the really interesting thing is the huge temperature difference between the rotor and the mounting bolts. This is the same reason the pistons have that beveled edge where they contact with the brake pad...this minimizes the contact area, and the subsequent heat transfered into your brake fluid, that could ultimately shift your bulk modulus...but all good brake set-ups use this beveled edge, so that's not really earth shattering. | ||
| Fullpower |
The stock Buell XB has some pretty good front brakes. Aftermarket pads from EBC (and possibly others) make them even better. Regular bleeding/exchanging brake fluid will keep the "feel" and lever travel as new. that said, a spirited romp on a KTM or Ducati fitted with the latest Brembo equipment will utterly twist your perception of what a motorcycle brake can be. Clean dry pavement, a hot sticky Pirelli and a pair of BREMBO's are almost as good as sex. That there is Fullpower quote you can take to the bank. | ||
| Rocketman |
You are almost as .................. Most folks, but Americans in particular, respect and are excited about individuals who create a product with their own two hands from nothing and become successful at it. We love that story. We each secretly dream to have one similar. Very few EVER make that dream happen. Now we're to believe Americans are the only ones appreciating their mad cap inventors burning the midnight oil down the bottom of the garden? I can think of no better example off the top of my head, of home made British talent, than this 48 cylinder fully working Kawasaki, and us Brit's are proud to have engineers like this fella holding up our engineering traditions.  This kind of creativity is exclusive to no nation, no colour, no creed. The world is full of geniuses, and Americans are not the only ones to appreciate their home grown talent. In any case. I thought Erik Buell was a German. Rocket | ||
| Rocketman |
Jeez, I just noticed, that lunatic isn't relying on the ZTL brake set-up. I reckon he must be one of Matt's customers! There really is no other explanation (excuse)  Rocket | ||
| Reepicheep |
This was a neat exercise! I think I got good readings with the IR thermometer. I had to move it all around (and find dirty spots on the rotor) but I think I had OK readings. Also, note that as embarrassed as I am to say it, I am probably pushing 260 lbs with all my fat, gear, and laptop pack. Short normal street ride on a 50 mph highway with stoplights and deliberately aggressive stops: Rotor: 125.0 degrees Caliper: 106.7 degrees Rim: 98.4 degrees Tire: 110 degrees Then I went out in the country and did terrible things to that rotor. Accelerate full speed up to 70 MPH, do an "almost stoppie" back down to 25 mph, accelerate back up full throttle, haul it back down. Did this maybe 10 times in half am mile and measured. *Boy* was that an eye opener! Rotor: Blue and smoking (maxed out thermometer, which goes up to 230 degrees) Caliper: 183.3 degrees Rim: 138 degrees Tire: 123 degrees I could feel the character of the braking change as that rotor started overheating. I also picked up more lever travel (last bled maybe 5000 miles ago), but was still only using 1/3 of the available travel at worst. Felt the deposits starting to appear on the rotor. Then finished my normal ride home with normal stop and go Rotor: 104.3 degrees Caliper 105.4 degrees Rim: 100.9 degrees Tire: 119.8 degrees The lever travel still feels a little more then it was (I need a bleeding anyway) but the deposits were starting to clear themselves up. Conclusions? The stock pads, while fine for normal street riding, do sorta suck. The rotor can accumulate a LOT of heat FAST. While the rims aren't magic in terms of absorbing heat (there was at least a 100 degree differential between the rotor and the rim) they do make a significant contribution (calculate the smaller mass of the rotor versus the significantly larger mass of the rims and the rim had been heated more then 50 degrees by the rotor, and the temperature was climbing). The ZTL brakes and stock pads are more then overkill for normal street riding. The ZTL brakes could probably use aftermarket pads for a track day. You can push brakes to failure if you are trying to push brakes to failure. Fun stuff! | ||
| Blake |
You didn't try the skin test? | ||
| Reepicheep |
I would have, but the whole "blue and smoking" thing tipped me off that it might not be a good idea... Lessons learned from self taught welding experiences | ||
| Ft_bstrd |
"Hey, anyone smell bacon? AAAAAAAAAAAHHHHH, SIZZLE, SIZZLE, SIZZLE!"  | ||
| M1combat |
I've faded the ZTL on the street. Afterwards I had a pretty obvious pulsing from the front brakes that I could feel in the lever. The pulse was not in braking power once I was on the brakes, but just in the lever if I rested my fingers on it coming to a stop using the rear brakes. I figured I had warped the rotor. I was pretty peeved that I had actually made the brakes fade, but I was also trying a new type of pads. They were Lyndall Golds. Al sent me a set of Lyndall pads that were more race oriented (Lyndall "HH" pads as I recall). I bedded them and then hit the spars in an effort to fade the brakes again (no bleeding or anything). I didn't. I also didn't fade them at the track. That said, I'm sure I'm not capable of the pace that Matt's rider is. Oh... After replacing the Lyndall golds the pulsing in the lever went away as well. The rotor is still perfectly fine... well... The inside edge has a definite "tempered" look to it when clean... I tried so hard to fade them that I was skimming the rear tire back and forth an inch or two coming into downhill and uphill braking zones from 115MPH down to 40. I didn't let up on it for four full trips of my canyon road. That would be about 35 miles and about 8-900 or so turns. They work for me... I haven't used the Lyndall golds again and I won't (too much dust) but it's entirely possible that I didn't bed them correctly. The Lyndall "HH" pads only lasted me about 700 miles too... strange. I've got EBC's on there now and they're alright. | ||
| M_singer |
Blake, Very interesting post about the moisture and how pressure effects it. makes perfect sense but never thought about that b/4. | ||
| Trojan |
From Matt's description, it sounds like he is talking about a all out brake failure, not fade. That is exactly what happened. Bruntingthorpe has a straight around 3/4 mile long with a hard right followed by series of bends at the far end. After just a short time the lever was coming so far back to the lever that eventually after just 3 laps the brakes suddenly just didn't work at all at the end of the straight. It focussed the rider's attention that's for sure! The XB12R used for the test had been supplied by H-D UK to the magazine in question so I cannot vouch for any service work carried out before the test. The bike had seized suspension adjusters front and rear and low oil level, so you can draw your own conclusions from that. However none of the other bikes present on the day suffered the same problems, and none had been specially prepared for the test. Our bike was exactly as it had finished the previous race meeting, the KTM was a dealer demonstrator and the other bikes were reader's bikes that they borowed for the day. Matt has a business to run selling parts to replace the "bad" ones on a Buell. Therefore his opinion is certainly as "biased" as Buell, and quite frankly, more likely so. I'm gonna vote for the Buell engineers for having superior knowledge, and being ahead of the world on this. I do of course have a business interest in aftermarket Buell parts, but that is nothing to do with my oipinion or findings. The brakes that I used on our race bike are not sold by us and I have nothing to gain by recommending them. I have given this subject a lot of thought over the last few days, and have come to the following (maybe wrong, maybe right) conclusions. The Buell ZTL perimater brake concept is absolutely sound, and it would take a far more experienced engineer/scientist than me to disprove the theory of it. To me the problem lies in between the design stage and the execution, where obviously the bean counters and men in suits have had an input into the final product. What we end up with is a watered down version of the original design that although looking the same will not perform as well simply due to financial constraints. If reducing unsprung weight is the ultimate goal, why does the stock bike have a cast aluminium front wheel and not carbon fibre, forged aluminium or even magnesium, all of which would reduce unsprung weight substantially but would increase cost? If you want to go all out for reducing unsprung weight then why is the plastic front fender so heavy? Surely carbon would be lighter and more efficient? If part of the theory is to improve braking over choppy surfaces, why fit the bike with relatively low tech (albiet adjustable) damper rod forks that are not capable of dealing with just this circumstance. State of the art cartridge forks would be much better, but again cost more. All of the above are no doubt influenced by profit margins rather than performance, and all take away significant parts of the theoretical benefit of the ZTL system. If you want to look at the engineers' version without the input of the money men, look at the XBRR. Magnesium wheels, Ohlins cartridge forks, lightweight carbon fender and bodywork etc. Recommending to people that they can fit the ZTL2 caliper to their road bikes isn't really the answer either, as they still won't have the same spec front end as the racer so won't get the full benefit. And why should a customer who has paid a large slice of his income have to buy an uprated caliper just to make his brakes work as intended? I also find the advice a little dodgy and maybe even dangerous, simpy because (as far as I know) the only pad compound available for the ZTL2 caliper is a race compound. These are totally unsuitable for road use and need to be hot to work properly. Using race pads on a road bike is inviting accidents to happen. Also, where do people buy replacement pads from? Not an item that the local H-D dealer or independant shop is likely to carry is it? Also not an item that the aftermarket pad manufacturers will bother producing given the tiny numbers involved, so the only alternative will be genuine Buell pads. How much is a set of pads anyway? If they are unavailable or expensive then people will be tempted to run the pads dangerously low before changing them, either by choice or lack of availability. | ||
| Spike |
This I find interesting: From Bill (Reep)-
From Don (M1)-
Here we have two cases of fade, one on stock pads, another on LRB Gold pads. My case was on LRB Gold pads, so make that 3 cases. In Don's case, a better set of pads seems to have fixed the issue. The only pads I've run on my XB have been stock and LRB Gold, and I've run into fade on both. I'm wondering if maybe the issue is that the LRB Gold pads aren't the suitable track pad that I thought they were. I've got a set of EBCs on order right now, I'll have to see how they do. Maybe this is the excuse I needed to justify a track day to my wife this season. | ||
| Skully |
Also, where do people buy replacement pads from? Not an item that the local H-D dealer or independant shop is likely to carry is it? Also not an item that the aftermarket pad manufacturers will bother producing given the tiny numbers involved, so the only alternative will be genuine Buell pads. (Hi Matt!) American Sport Bike carries a good selection of aftermarket pads for XBs all for around $50 USD. I purchased the Nissin 804 pads that I use for racing from Appleton H-D and I recall paying $60-$65 for the set. The stock pads did cause a heart attack going into Turn 2 at Oak Hill as Blake described above. However, after switching to the Nissin 804s, the brakes were solid even at the end of an 8 lap sprint race. | ||
| Trojan |
Hi Keith, Sorry I didn't mean pads for the stock brake, but for the ZTL2 8 piston race caliper. I don't know of anyone offering pads for this yet. (Message edited by trojan on June 14, 2007) | ||
| Josh_cox |
Only Buell (Nissin) does. They are H0300.05AH PADS, brake (set of 4) $179.25. As of right now they are the only ones I know of for that caliper. The last a long time and work great though. They are a different compound than the 804. They have a little more initial bite and seem to last at least as long if not longer. Josh | ||
| M1combat |
I think in summary we (most of us) have found that the stock ZTL brake with a pad swap works just fine in nearly all conditions. The XB "package" doesn't stop as quickly due to the geometry but that is NOT a function of stopping power overall in the brake system. Where the ZTL "system" shines is in allowing the manufacturer to use the same suspension components as their competitors (read - Same cost), but they get better performance out of the suspension itself. In my opinion this is worth it due to the fact that if one were to give the competition a material and technology upgrade (at a price upgrade) one must do the same for the Buell and it again comes out on top with regards to suspension efficiency. I can personally attest to the claims of enhanced performance on the brakes over bumps and mid-turn over bumps. This effect is greatly exaggerated the more choppy the bumps get. When you get to washboard bumps the XB just plain sticks, where other bikes chatter. This costs corner speed and brake distance. The other factor is the safety one. We all go a little too fast on public roads from time to time. Even the ones we haven't run 1000 times. When you come around a turn too fast and hit some washboard bumps it's a defining moment . The XB is the one that is defined as the one that works better in that situation. | ||
| Reepicheep |
Keith... Would you recommend those pads for street riding / novice track days? Or would you characterize them as a race use only pad? Thanks! | ||
| Thepup |
M1,you have rode an old UJM and your Buell,just how does that make you an expert on how other bikes brake? | ||
| Disturbed |
Test post per Blake. ^_^ | ||
| Skully |
Hey Bill (Reepicheep) - Yes, the Nissin 804s work great on the street. They do have more initial bite than any other pad that I have tried. The first time I rode in stop and go traffic, I really had to learn to be very gentle with the brake lever. It wasn't a concern with locking up, it was front end dive. I run much softer compression/rebound settings on the street than I do on the track. Keith |
