sticky front brakes

Hi, can somebody please help me out with a problem I have with my 2000 R1. The front brakes seem to drag excessively (by that I mean if you jack the front wheel up and try to spin the wheel, it might spin about 1.5 revs before stopping). I have stripped the calipers down and cleaned the bores, pistons and seals but with no improvement. The disks and pads aren't badly worn (so the pistons are pushed out a long way) and there's no corrosion around. The binding is not attributed to the bearings as the wheel spins OK without the brake pads in. I have noticed on other R1's that the front wheel spins far more freely. Thanks for your help

right, you need to bleed the brake lines/system. bleed them and fill with new brake fluid, then try spin the wheel

hi, thanks Graham for the ultra quick reply. I've recently fitted SS braided lines and bled them (no more air to be seen). They feel fine and not spongey so I guess they are good. The disks aren't warped so I'm stuck for ideas now ?

they are fine then. get used to them first

thanks for the help but I'm not convinced they are right. I only do track days on the bike now and it feels as if the front wants to tuck a little cornering. This does not inspire confidence. As I said earlier I have checked quite a few bikes (R1's and others) and the front brakes don't bind anywhere near as much.

I have found this to be a somewhat common problem on r1/r6's. They do have a bit more brake drag than other bikes. On my r1 when i notice the brakes dragging I just unbolt the calipers and clean the pistons and the seal (without taking them out!!). Do not EVER push the pistons inside the calipers without cleaning them of all grime first. It will shove some of the grime into the caliper bore. This is an often overlooked step. Most people just shove the dirty pistons back into the calipers to put new pads on without cleaning anything. Unless you have too much fluid in the syatem, bleeding the system will not help cure brake drag. Use emery cloth or fine sand paper to clean the pistons throughly. 9 times out of 10 it will free everything up. Also you can take the brake pad spring on top of the caliper off and throw it as far as possible. It is there to help fight brake noise, but I have no noise and have not had them on in 30k miles. Take the brake pad retaining pin and clean it, best is to use a wire wheel on a bench grinder but you get the idea. When you put the caliper back on the disk, first pump the brake lever a few times to make it just too tight to fit over the disk. Then slowly wobble the caliper over the disk, letting the disk spread the pads slightly. This may sound counter intuitive, but I assure you it is correct. Ever notice that your lever travels a bit more than you would like, or more than it used to? You still have the same brake power, but the lever has to physically move farther than it did before to get the pads biting on the rotors. Here is the reason why, and the reason I say to pump the lever before instillation and use the disk to spread the pads: There is a square section rubber seal that seals the brake fluid in the calipers, and more importantly is solely responsible for pulling the brake pads away from the disk when you let off the lever (or pedal). See when you apply brake pressure and the pistons are driven out of the calipers it distorts the rubber seal, and when you let off the lever the seal has some spring energy as it is streached out, so the spring energy brings the seal back to it's normal shape and brings the piston back with it. It does not pull the pad back, but without any pressure on the pad the bike rolls freely (plus the vibration will help kick the pads out a bit, a very small amount). Now what happens it that as the pad wears the piston is meant to slip past the rubber seal farther and farther, so that the same lever travel is always used to get the same result. In the real world though the seals will dry out a bit and stick to the pistons, and they will not let the pistons slip past the seal any. What this means is that as your brake pads wear you have to use more lever travel because the pistons are being pulled back into the same old pisotion as it always has been, even though the pads are thinner now and have to move farther to touch the rotors. This makes you move the lever farther before the pads bite onto the rotors. By pumping the lever a couple times you will break the seals hold on that particular position on the piston, and force it out farther than it needs to go. The piston will be wet where the seal touches it now, and as you use the disk to spread the pads the piston will move back only as far as is nessairy, and the result will be a firm lever with shorter travel. Just like it was when it was new. So long story short, push the pistons out a bit and clean them throughly with emery cloth. clean the brake pad retaining pin so that the pads can slide smoothly. Throw away the copper colored spring (it traps heat and brake dust), and use the disk to spread the pads out to where they need to be. You do that to both sides and you will once again have a free spinning wheel, and a firm lever. If you have a new bike (or brake system) you may not notice the lever traveling any less than before. That means that either the seal is not stuck to the pads or the pads have not worn much yet. This is most usefull to bikes that are a couple years old and in need of brake service. Good luck.

Hi, thanks for your very detailed reply. that all makes perfect sense now. I have completely stripped the calipers and cleaned the seals and noticed that they had a 'set' in the rubber. i.e not completely square. I think this may be contributing to the binding. Think I'll splash out on some new seals, pads and DOT5 fluid. BTW the Red 00 R1's are the fastest (at least on my track days !!!):bow

use dot 5.1 not 5. the 04-05s have a much looser pad fit than the earlier bikes and all drag is gone. I would check your pads and make sure they are not too tight in the caliper body and rsize if needed.

right, I've got my new genuine Yamaha caliper seal kit (how expensive was that !!!) and am ready to fit them this w/e. Anybody have a good tip for getting the pistons out from both sides of the calipers. Last time I did it I found it a real a*$e job, as one side would pop out first (I used an airline on the caliper to blow the pistons out). cheers guys :fire

Your problem may not be with the brakes at all... The first thing you should do is loosen the pinch bolts on the fork legs... and bounce the front end off the ground in an effort to make sure the axel is not bound up in the fork leg.s... Try this... I have fixed a few racebikes this way.

thanks for the tip. I have tried this before and it didn't improve the binding (but I've heard it has worked on other bikes). I've just stripped the calipers and inspected the old seals. What I noticed is a small sliver of the outer dust seal had broken off and worked it's way down past the main seal, probably causing increased interference between the piston and seal. Unbelievable really ... Anyway after a thorugh strip down, new seals and a good bleed it now spins nice and freely, so I'll stop going on about it now. Cheers for all your help and advice guys

congrats on a job well done my friend :)

Hey Spike, I have a 2000 R1 and have the same exact problem. Just ruined a perfectly good track day. Where did you get the seals. Did they have a kit or did you have to order each seal. I've checked a few oem micro film sites and It's a little vague on whether it's per caliper or for both. BTW Nice post JAYSTENSEC4CYL Thanks Brad

Hi, got them from a Yamaha dealer direct. A seal kit (dust and main seal) per caliper if I remember right. Expensive, but with a bit of cleaning and a little TLC they have been as good as gold since. Done quite a few trackdays since with no issues. front feels so much better with none of the front tucking feeling that was there before. Also when I change my front wheel I always bounce the front before I tighten the axle pinch bolt. This lets the forks settle better. Hope this helps enjoy your trackdays again...

Try cleaning the rotors with brake clean I do it after almost every session on my race bike.

What a brilliant thread, just wanted to bump in case this helps others and say thanks to JAYSTENSEC4CYL and Spike for 'sticking' with it till the problem was gone (pardon the pun) :rock

Hey sorry about the late post to the fix I bought new O rings and installed with no fix. Noticed FINALLY that one piston would stick and the other pistons would come out and seat and the sticky one would come out last and you guested it STICK drag the brake over heat and fail. So I took the pistons out polished them with fine emory cloth and then polished them with 2000 grit sand paper. This made the FRICTION the same on all the pistons and they worked good as new!! Finally. Brad :rock

Road ATL with NESBA

By the way I didn't come up with the idea if you read the post that way. Thanks to Jay THE MAN! Brad.

any time guys :) Glad I could help :) Great idea about usinf brake cleaner on the rotors at the track. What brand do you use if you don't mind me asking? I have found that some of the brake cleaners leave an oily residue thats terrible for the brakes. I have been using 3m brake cleaner here lately with good results.

Jay, stop giving away all our trade secrets!!! LOL Only joking mate, top info that more people should know. I'm all for safety :) One thing I'd like to chuck in is it's amazing how many real problem bikes I get passed from dealer to dealer because they can't stop the brakes from binding before I find out their wheel spindle is bent. I know it sounds stupid but it's more common than you think. Back to 'normal' binding brakes, after you've stripped and cleaned/serviced them, it's much faster to draw the new fluid through an empty system at the caliper bleed nipple end with a syringe and some clear (so you can see air/fluid moving) then to spend ages pumping away at the lever. The lever can't move the volume of air in the empty system fast enough to start pushing fluid through. I have loads of brake tricks but I've got to pop and pick a customer's bike up, will write more tomorrow :thumbup

Right, just a couple more tips that may help people with brake problems... Jay's already given excellent info about sorting binding brakes but my few tips are more to do with bleeding problem brakes or brakes that are spongy... While I remember though, some bikes (not R1's) use shaped caliper seals that will only work properly if installed in a certain way so pay very close attention when you're taking the old ones out. You don't see that much anymore on modern bikes but worth noting. Still on caliper seals, when I install new ones I coat them very lightly in a special rubber grease (I get mine from Wurth but I'm not sure what other makes there are out there, I've only ever used Wurth) and this helps prevent two things, and road crap getting into the grooves in the caliper the seals sit in, and stops crap adhering to the seals themselves. I've found doing this, the brakes need cleaning/servicing much less often. Make sure the grease you use is both brake fluid compatible and won't harm/cause the seals to swell. Never clean seals in WD40 as this causes rubber to swell. That's why they make specialised brake cleaner! Right, for bleeding problem brakes assuming calipers/master cylinder and hoses are all in top condition... Firstly, you may notice that your master cylinder is above your brake calipers (!). You're trying to bleed from the lowest point in the system and air's not a friend of that setup. There's a few things you can do to make your life easier and get rid of as much air as possible, preferably all of it. Ever noticed how really expensive and trick master cylinders have a bleed nipple attatched to them? http://i119.photobucket.com/albums/o128/marcaztls/Brembomastercylinder.jpg This is to eliminate, or at least make it much easier to get rid of all the air trapped inside the master cylinder. Don't worry, you don't have to rush out and buy some new jewellery for your bike unless you really want the excuse! Most bike shops will be able to supply you with one of these fella's. Make sure you get the right pitch thread though :) http://i119.photobucket.com/albums/o128/marcaztls/Banjowithbleednipple.jpg This replaces the banjo bolt joining your hoses to your standard master cylinder and allows you to bleed from the highest point of the system. They are available in double length too if you have twin hoses attatched to your master cylinder. I've solved many soft and spongy brake problems with one of them :) I also apply PTFE tape around bleen nipples, taking care not to cover the hole, which makes a better airtight seal and sometimes a much less messy job is brake fluid leaks past the nipple while you've got it undone to bleed. Not so much to note on R1's or bikes with a remote reservoir on the master cylinder, rather the type with a built in reservoir where you can look in and see the fluid holes is to very slowly and slightly move the lever in and see the air coming out of the calipers/lines and into the reservoir. This sometimes helps when installing new lines full of air. Another tip is to take a good look at your calipers, there's lots of spaces air can hide in them when they're mounted to your fork legs and you're trying to bleed them. Unbolt them and roll them around to allow air trapped in them to rise to the bleed nipple on the caliper. I generally do this as one of the last jobs after you've got rid of most of the air you can bleed out normally. I've sometimes had to do this with master cylinders too and even been known to remove a complete brake system from a bike, hang it and bleed it through before putting it back on the bike as long as the setup allows you to do this. My last tip is when you have finished bleeding your brakes, take an elastic band or your missus' hairband, or even your own if you're still stuck in the 80s and won't give up the ponytail and use it to bind your lever on overnight. I don't mean yank on the lever until you're bending alloy then strap it up but just enough to apply the brakes which will open the master cylinder path up and allow any microscopic air bubbles to travel out slowly overnight. Just try this with your current setup and you may be surprised how much firmer your lever is. I do this preferably with the master cylinder lid off but cover it with a piece of rag to stop dirt etc. entering. Oh, that wasn't the last tip. NEVER shake brake fluid in it's bottle. It will trap air in it which will make bleeding a nightmare. Brake fluid is also hygroscopic meaning it absorbs moisture from the surrounding atmosphere. Because of this, never leave the top off a brake fluid bottle longer than you can help and change brake fluid regularly. I do mine as often as my engine oil and find it a good routine to get in to. Can't think of anything else at the moment but if I do I'll post it here. :thumbup

Someone asked about popping the pistons out. I wrap a towel around the caliper half and apply compressed air to the hole where the brakeline went in. This prevents the piston from flying across the room. One of the pistons will come out. Then, put that piston back in, but lightly. Wrap the towel around both pistons, but hold the loose one with your hand so that it won't pop out, which will force the other one out. The loose one will come out by hand, and you are done. This is for those who never did it before. I had a rough time figuring out a method to get them out years and years ago. Derek