Front Brake Pulse

[leakyrat]

I bought a 2005 XB9X last fall that was barely running and had a lot of issues. Been fixing it up over the winter.

The main issue that I'm still having is the front brake. Last year (and now), when I brake the lever pulses with the rotation of the wheel. Reading through this forum and some others it sounded like the pulse was due to uneven brake pad material build up on the disk. So I removed the disk, carefully sanded it, cleaned it all up with brake cleaner, and re-installed. I also put on new pads and flushed the fluid.

But the lever still pulses, once with every revolution of the wheel. So at higher speeds it feels like a vibration, and at lower speeds the pulse is more noticeable. At really low speeds (walking) its almost like the brakes catch a little bit every time. The lever goes in a little and then gets pushed back out for the rest of the disk rotation. I just measured with a digital caliper, and it looks like the disk is about 0.1mm thinner at this point, but it's hard to measure accurately and I don't have a micrometer.

Has anyone had this happen? What would even cause a disc to get thinner in one small area? This bike has seen some **** but otherwise the front wheel and the disk look straight. Or could it be my mounting? I cleaned and re-used the original hardware. I was looking at a set of the new solid mounting hardware but it'll be over $100 to get it up to Canada, and EBR doesn't even have it in stock right now.

I'm just hoping I don't have to buy a new disk, they're about $400. So I'm open to any ideas. Could I get the current disc honed? It's about 4.65mm at the thinnest point and 4.75mm everywhere else.

Thanks,

 

[user_deleted]

if the brake pads are decent....and the pad mounting pins are in good shape with minimal visual wear....and the calipers pistons are moving freely....and the rotor mounting hardware is in good shape and the rim spring holes are clean....and the rotor is floating meaning you can push on it at any of the mounting points and feel it freely move in and out however slight....then the rotor is warped and needs replaced. good news is i stock new EBC rotors and sell that at 10% over dealer cost to board members. about 1/2 your quoted price shipped to most canuck provinces.
believe me when i tell you that nobody loves buells more than i but i absolutely loathe the ZTL braking system. you're not alone with your problem.

 

[leakyrat]

Hey Lunatic, thanks for the info. Everything else looked good when I took it all apart. New pads and cleaned up all the hardware. Disc moves freely to bottom out on the rim - about a mm or so. And thanks for the offer of selling some new parts, PM sent.

I love the brake and the thought behind it, but I'm starting to learn that maybe it isn't the best in practice.

Does anyone have thoughts on reusing the mounting hardware, or switching to the newer EBR solid mount stuff? Is there a difference, or is it worth the price?

Any ideas on what to do with an old disk? Clock? Frisbee?

 

[user_deleted]

my pleasure. received your PM and email sent.
i always re-use stock mounting hardware if the oblong shaped rotor washers are in good shape and show minimal to no signs of wear. in all honesty i know some rave about how improved braking action is with the EBR solid mount hardware but after trying it on perhaps 6 different bikes never noticed any difference. i ride like the 64 year old geezer that i am so take all that with a grain of salt.

 

[njloco]

Still wet behind the ears !

 

[Cooter]

On re-installing the rotor, don't forget the first square washer has a particular orientation:
The smaller radii on the edges go towards the outside of the rotor.

 

[leakyrat]

Hey Cooter, ya I saw that and I'm pretty sure I put them back in the right orientation. You're talking about #66 in that image right?

Looking forward to the new rotor.

 

[Silverrider]

Like the guys are telling ya, ^^^^^ I usually clean all the washers and rub them in a circle motion on 600 sand paper with oil , cleans off all the miles of grud.

 

[sinikl]

i too have a pulsing front brake and am watching this thread with interest. Leaky, tell us how great your new rotor is when you get it, in the meantime i guess i'll try to do the due diligence to check mine over. Mine is either getting better over time or i'm getting used to it (probably the latter) so i'm hoping i have uneven pad deposits on the rotor.

 

[Cooter]

Ya, #66.

Cleaning and lubing the hardware is free and should be done anyway. I use anti-seize. If thats not it, get a high quality rotor (from lunatic).

I'm one of the ones professing their :love_heart: for the EBR race hardware kit, but I will admit I noticed the biggest difference on my CR track bike... at the track. I would trail brake turn 1 at PBIR so bad the stock rotor turned blue. The EBR rotor and solid hardware stopped that entirely and felt way better:angel:

 

[leakyrat]

I wiped everything down with brake cleaner, but I'll be sure to give it all a quick sand when I take it apart again.

Cooter, for the anti-seize is that a coating on the washers and spring? Or on the bolts as well? Or do you thread lock those?

sinikl, mine feels pretty sketchy, like I shouldn't be riding it, which I'm pretty much not right now. Just some short trips around town. At high speeds the vibration from the front when braking feels like it's going to back out some bolts. At low speeds it makes the front dive, it's that bad. I have no idea how the PO could ride it. So I'm barely touching the front brakes, mostly using the rear when I do take it out.

I'll check out the EBR hardware in the future when I can justify throwing more money at this pile. Nothing more expensive than a cheap Buell apparently

 

[Cooter]

I put anti-seize on everything and torque the bolts. I don't know if loctite is specified for those bolts in the manual but I've never needed it. I have had a few nightmares trying to un-do it though....

 

[leakyrat]

I finally had a chance to finish putting the new parts on and take it out for a ride. The new footpegs (stock) were an inch lower than what the PO put on and they're a way better position. Makes sitting on the bike more comfortable and I feel less folded up.

The front brake felt so much better it's like night and day. Just a smooth solid braking feel. No pulsing, and way more control.

Putting on the EBC rotor was a little annoying. The cutouts for the thick square washers were too small and I had to file down the inside of the cutouts, and grind down the sides of the washers slightly to fit in. I could have forced the disc on by just tightening the bolts before grinding to fit, but then the disc would have been stuck and wouldn't have had the designed in float.

Now the downside. I made it about 3 blocks before my dash totally died and I had to pin the throttle to keep the motor from dying. I made it back and my battery read 11.8v which is basically at 0% charge. So here's another money pit I'll have to deal with.

I'm hoping the regulator and alternator are good. I'll be checking that tomorrow.