| Author | Message | ||
     Tatsu |
I think my front rotor is warped. When I "get on" the brakes. The brake lever vibrates and the front end shakes. I just had some new pads put on about a month ago. When I squeeze the brake lever lightly I can fell the pads, rub then not rub. What causes the rotor to warp? Is this something that is going to common to the particular design of the rotor? | ||
| Fullpower  |
happened to mine , dont know the cause. just ride mine on the street. get a new rotor, before you need a bunch of brake and it aint there. | ||
| Captainplanet  |
Tatsu, Make sure its not your head bearings being loose. It can feel pretty much the same as a warped rotor. | ||
| Reepicheep  |
If they are warped, you will have a lot of lever travel. I had a rotor bent when somebody was mounting a front tire (grrr). The brakes pumped up fine after mounting the tire, headed down my steep driveway for a test ride, hit the brakes as I was approaching the bottom, and... Clank (lever against bar, oh crap) Clank Clank (keep pumping... oh crap). Clank Grab (whew!). Its unnerving, as when the bike is stationary, they pump up fine. It's after the wheel rolls that the pistons are pushed back excessively by the warped rotor and you have to pump up the system to get enough travel to engage the brakes. If travel is still short, but the pulsating is still there, could be glazing / brake pad material infusion into rotor. | ||
| Fdl3  |
I bought my XB9R used. It came with a warped rotor. The front brake would pulsate like you describe. I have since replaced the front rotor and brake pads. Pulsation is gone. Rotors warp for many reasons. Real thin rotors are more susceptible to warping. Excessive heat will cause a rotor to warp. It is my opinion that one too many stoppies will warp the front rotor. I wonder, too, if the large perimeter disc is more susceptible to warping. Warp 9...Engage! | ||
| Fullpower |
no stoppies on mine, bought it new, only ridden on the street. tried changing pads a couple times, tried "glaze breaking" a couple times. chucked up a rubber fingered abrasive disc in a die grinder and went at the rotor a couple times. retorqued the stearing head bearings a few times. each of these helped a very little bit, but the brakes still sucked •••. i rode 5000 miles with the problem, then let my brother ride the xb and he freaked; said the brakes were dangerous, how can you ride that in traffic? went for a ride on the sportster, and realized that it had 4 times better brakes than the buell, so put the bike in the truck,(first time i have had to do that) dropped it at the harley shop, said i would not come back for it till it was safe to ride. they fixed under warantee. new rotor. brakes are good now. why did the rotor fail? i dont know. now running EBC pads on the fresh rotor, stops real well, very easy to modulate, very strong, it has maybe 75% of the brakes that wifes ducati monster has, which is damn sure plenty of brake for the street. | ||
| Tatsu |
Yeah I gotta get this fixed! It's bugging the crap out of me. I hate that chuuuuggggggingggg stop when on the brakes. | ||
| Freyke  |
cap nut! | ||
| Aydenxb9 |
It may not be the rotor itself but the "floaters" the rotor rides on. Y'know, those pieces of plastic that the rotor sits on and rides around rotor bolts. They may be siezing the rotor which will cause a pulsing sensation. | ||
| Tatsu |
Well the bike has an appointment on the 28th so we shall see, hopefully. (Message edited by tatsu on December 16, 2004) | ||
| Tatsu |
Was thinking. I mess with the suspension a lot, is it possible to have one side of the suspension a little off and have shudder in the brakes? I think I'll go and make sure I'm back at the factory settings. | ||
| Noface  |
I think Aydenxb is more correct, at least in my situation. I've had the same pulsating brakes on my 03 9R. I took the rotor to work and checked it on a Starret table and dial indicator. Though this rotor has 20k on it, it's still flat as a pancake. I deburred and polished the mounting hardware, and wha'la. The brakes now work fine. I think when you order a new rotor from Buell, it comes w/new mounting hardware, which may explain what possibly fixed Fullpower's situation. | ||
| Tpoppa |
Tatsu, If you feel it at slow speeds (under 25mph), under light to medium braking, it is the steering head bearing. If you feel it every time you use the front brake, it is probably the brake rotor. | ||
| Tatsu |
Okay thanks for all the input. I'm still trying to figure this out. I just remembered in my last check I had the fork oil replaced, so I went out last night a adjusted all the suspension setting to the recommended. That seems to help a little. I think what I might do is ask the dealer to test ride a new XB12R and see if it's the same. If it is, then it's just me being picky. I just don't have a baseline to judge from. | ||
| Fullpower |
Tat: pulsating or shuddering brakes are completely unacceptable. no you do not want to "get used to it" and i dont think you are being picky at all. i was getting used to my screwed brakes for thousands of miles, and had to ride go for a ride on my sportster to remind me what good brakes should feel like. the XL has floating rotor and a 4 piston PM caliper, and it stops as well as the bias metzeler will permit. the new rotor and included hardware absolutely cured my XB12 brake problem. interesting comment from noface, about the possibility that it was burred up mounting hardware causing my problem. i will investigate that further. get it fixed before you need a bunch of brake. good luck. dean | ||
| Goldenboy9r |
mine is warped bad. anybody know the price of a new one off hand? I had a service manager tell me the springs will go bad behind the rotor?? | ||
| Kashmir |
Tatsu - You're getting solid advice from guys who know: Get it fixed, then stop worrying about it and go have some fun. In my tiny little world, a brake disk is something to get excited about; I especially like the look of the big ol' disk on the XB's. It makes a unique and unmistakable visual statement out there on the front wheel. Brake disks warp due to lots of reasons, its likely that nobody will really be able to tell you what exactly happened to yours. I'm gonna turn straight nerd on you in a couple of paragraphs, so here's what you probably wanted to hear before I finally loose all credibility: Disks can warp because you got'm too hot and residual stress left in the material by fabrication (and not resolved during the heat treatment)caused them to deform. The metal gets a little bit softer when it gets hot; we're not talking "heat-it-and-beat-it" soft, but then a deformation of a couple of thousands across a rotor can make it un-usable. Sometimes a rapid cooling can make the problem worse - say, getting a good splash of water right after a hard run; that kind of thing can happen you might not even have noticed. Disks can also fail due to fatigue; tiny defects created by cyclic loads, shock loads, and thermal transients add up over time, all those little defects can work together and cause a solid-looking piece of metal to fail. I'll bet your's didn't have anywhere near enough miles for that, but it can happen. And if you got through that, here's where I loose it big-time: Amazing stuff, modern brake disks; imagine of a ring of metal: Thin and light, to minimize moment of inertia. Corrosion resistant across a wide thermal range. Hard enough to resist abrasion, yet ... Tough because it must stand up to cyclic compressive loads cyclic thermal transitions (different kind of stress) occasional intense shock loads Machined to breathtaking tolerances Heat-treated carefully, to enhance durability (trickier than you might think!) Drilled and slotted, then finished to be attractive, but not overpowering Designed for endurance, beauty -- Even the stock disk is sculptural Dependable enough that you'll repeatably bet your life on it, without even thinking Mass produced with stunning consistency Cheap enough so you and I can both go afford to buy one. Now, stop imagining, and go get a new one of your own; It'll feel like a brand-new pair of shoes when you get it back from the shop. All this about one little component. Modern bikes (Ours, the Euro-stuff, and the Rice) are a technological wonder. Its astonishing that we get priviledge of riding something this cool in a world this amazing. Kinda makes you want to be a better rider. (gulp - sorry!) drp | ||
| Tatsu |
Yeah I have an appointment set for the 28th, gonna get it checked out. Thanks for all the advice. | ||
| Roc  |
I have a bad shudder now too, lame. I think it is the fasteners brake/wheel and will check them next. | ||
| Charlieboy6649  |
I have to agree with Captain, For Gods sakes torque what you can before you spend high dollars. My wifes XB was pulsing at the lever below 25 mph as she was approaching stop lights. Torqued the cap nut to spec and voila! Her caliper was also siezing and dragging the rotor = excessive heat. So a little brake cleaner solved that before any damage was done. Just don't spend the $$ if you don't have to is all I'm saying. Check all avenues. Would suck to buy a new rotor and still have it shuddering... | ||
| Wyckedflesh  |
Tatsu, since you have an appointment, I take it you will be going to South Seas HD right? See if they will meet you halfway and pre order a rotor now so they have it instock when you bring in the bike. If its warped then they already have it waiting, if its not offer to purchase it and just have it on hand for when you are out of warrenty. As long as the rotor lays flat in storage it will not warp. I just know how long it takes for parts to get delivered here on the mainland, and remember dealing with warrenty parts in Hawaii... I know in the case of my rotor, it had hot spotted so bad it acted just as if it was warped. Replaced the pads, and took a surfrace prep scothbrite pad for gasket removal on a cordless drill to brake up the glazed hotspots and haven't had a problem since. | ||
| Tatsu |
Actually that's good advice.. I think I will do that. | ||
| Wyckedflesh |
hey while your at it...I could use some Guava Syrup from Eggs N Things  Oh and well while your there, have a plate of Big Island Smoked Chops too damn I miss that place...and the food | ||
| Tatsu |
I can get the Guava Syrup! BadWeb discount.... nah just kidding. Actually I will be taking the bike to Cycle City, which just opened up a huge new HD shop that looks more like a museum for HD. Two floors, huge floor space. Very nicely done. | ||
| 1badxb |
Gotta watch washing your bike after riding for a while the hot rotor getting hit by water will warp it. Just a thought | ||
| Wyckedflesh |
GAH! My bad Tatsu I was looking at a pic of my daughter in her South Seas HD jumper when I said that. I knew you would be going to Cycle City...damn I hate when I do that. | ||
| Unchi |
my turn....... brakes warp for several reasons most of which are listed above but the most common is you get your brake very hot be it in the twistys, stoppies, etc. you come to a light and stop where does all the heat from the rotor go ? right thru the pad. SO that part of the rotor cools faster than the rest and warps the rotor a little bit. Do it over and over and over and POOF warped rotor. BEST way to prevent warped rotors is to release the brake if u can once stopped, or use the back brake to hold you still. Also have your rotors Cryo'ed increases strength by 40% and can virtually elimate warping. a good racer friend used to replace his rotors every race(cage) because he was only allowed to use stock size. he had 2 sets cryo'ed and has yet to use his second set this season because his first set has not yet warped. just my 2 educated cents | ||
| Tatsu |
Who does Cryo'ed and how much does that cost? | ||
| Unchi |
http://www.frozenrotors.com/ http://nitrofreeze.com/index.html Local to me (Message edited by unchi on December 19, 2004) | ||
| Tatsu |
Hmmmmm.. very interesting frozen rotors. On a side note. Went to get a rear tire at the dealership. Told them I'd had an appointment for possible rotor warp on the the 28th and asked them if they had any rotors in stock. The guy said no, but then promptly said he'll order a rotor as parts so in case I needed it would be here. I was like cool! I might even buy it off them just because. |
