After issues experienced with my brakes on my previous track day. I swopped my brake pads and fluid.. Worked a treat. .. However I used my tyre warmers today and I realised my front wheel battles to turn when off the ground. After removing the brake calipers, the wheel turned fine. It seems the right caliper is gripping the disc so much that I can barely move... Any ideas?

LOL - when I first read "... my front wheel battles to turn when off the ground ..." - I thought, well duh - hard to steer while wheelieing.

Yeah - sticking piston(s). IMO, most likely the caliper (could be in the MC ...) Which may have been your problem in the first place (as was suggested by some in the other thread).

In the mc ? The pistons move freely if i lever with a screw driver? As for wheeling...need to get it sorted on 2wheels before I move to one

Pump the pistons out and give them a good clean. When they are dry smear a tiny bit of grease on them and push then all the way back in.

See how that goes.

Be carefull not to pop them out of the caliper when you pump them out.

I had this issue, it span maybe 90 degrees freely before stopping.

SO I took the calipers apart, cleaned throughly, new seals, pistons cleaned etc.

Made feck all difference

It's not the pistons in the caliper although they can eventually degrade. The brake dust, road grime, etc. can eventually build up to the point of restricting the piston from retracting into the caliper bore. This willl happen on both the LH and RH side calipers equally.

From what you've posted this is not what you are experiencing. You have a mis-alighnment condition at the fork tube/axel interface. If you take a close look at how the axel pinches the bearings you'll see that by tightening the axel nut it pulls the shouldered section of the axel against the bearings which pulls the wheel against the LH side fork tube. The RH side fork tube is designed to float on the shouldered section of the front axel to allow alignment of the fork tubes (and by default the RH side caliper on the RH side rotor which is attached to the wheel).

What you need to do is loosen up the axel pinch bolts on the RH side fork drop out, and, with the bolts on both LH and RH side calipers loosened up just a bit (finger tight), grab the front brake lever and pump the front of the bike up and down several times with a lot of force. This will align the RH side fork tube on the axel (ie, move left or right-whichever direction it needs to), align the pistons inside the calipers, and align the calipers with the rotors. Don't let go of the brake lever. Keep pressure applied to it and tighten the caliper mounting bolts and RH side axel pinch bolts. When the pistons retract into the bores of the calipers the wheel will spin much more freely.

Take a look at it and you'll see what I mean.

Good luck.

Good spot mate if this is the case.

I do that "bounce" as a matter of course everytime I change a front, which is fairly often with a track only bike.

It's a quick place to start IF he didn't do it after a wheel change.

Had tyres fitted and they definitely didn't do that.. will give it a try and get back to you guys later..

One other thing you might want to try (I do this every time I pull either wheel) is push the pistons back in the calipers by holding the rotor with your finger tips and pushing on the caliper with your thumbs. This works the outer pistons back into their bores. Do the same for the inner pistons.

This does two things. Any air that may be trapped in the line, upper banjo or MC gets forced back into the resivoir and assures you the pistons are moving freely. Makes it much easier to replace the calipersas well. It also gives you a good starting point to get everything lined up properly.

Again, once pistons are forced back into the bores, finger tighten the caliper pinch bolts, spin front wheel while pumping front brake lever. Once pads have made contact with the rotors hold the brake lever and tighten all hardware including the RH side fork pinch bolts (at least one). Get them as tight as you can while holding the brake lever so they wont move during the final torque application.

As SDNerd (and others) have said, not a bad idea to pump the pistons out a little and clean them up if they are hanging in the bores.

Let us know how you make out.

Is it correct in saying I only have 2 pistons per cliper and the pads on one side do not move?

Ok tried it.. Loosened the pinch bolts on the bottom of the forks, loosened the caliper bolts, held the brakes, pushed the forks down..tightened the fork bolts then the calipers... Still tight. Was thinking of loosening everything and taking a slow ride around the block.. Then tightening it all when I get home... Will that help?

Looks like mine only have 2 in each caliper... I think the 2 on the inside of the calipers are stuck..

Ok.. Will give it a try..

You calipers definitely have 4 pistons each. When you pull the calipers off and push all pistons back into the bores hold the caliper upsidedown and apply the brake lever a few times. You should see all 4 pistons moving out of their respective bores (maybe not perfectly equally but close).

If not your job just got a lot bigger. Don't pump too many times or one of the pistons could pop out. Do one caliper at a time or have a mate hold both calipers upside down and check them both at the same time.

Kind of hard to explain all this stuff on the forum. If I were there we could have this sorted in literally 15 minutes (provided your pistons are not stuck in the bores).

Good luck.

One minor note about pushing back pistons: You may want to remove the MC reservoir cap, and be prepared to siphon off some of the fluid. I suggest this possibility as you just flushed/bled the brake lines (right?), and if the MC reservoir was topped off, things could get messy in this process if not prepared for that.

Apologies in advance if being "Captain Obvious" with this addition.

I think that this paricular bike should be worked on by a qualified mechanic.
I have seen first hand what happens when you suggest possible remedies to someone that is not of the wherewithall to complete such actions and asks questions that would be big red flags to the helpers to stop and wonder if advice could end up in the wrong hands. Sort of like telling someone how to clean a gun when they ask where to load the bullets and how many of them is it supposed to hold..
How many pistons was thay again?

^^^^^^^^

You obviously have better mechanics then we do.. here you pay a fortune for a pimple faced teen to work on your bike, as the experienced mechanics have better thinks to do , like pick their nose and tell each other how great they are!... no thanks, i am more than capable myself

Hi guys, i have taken some pics... how can i get them on the thread?

I cant figure out how to load the pics here.. but after checking last night.. it looks like the right hande side caliper (if you are sitting on the bike) is too far right. The piston is fully retracted and the pad is against the caliper, however it is still rubbing against the brake disc as A result the pistons on the other side of the caliper are fully extended, in order to make contact with the disc.

I thought mabe the one sides pistons where stuck but when I push all the pistons back and put a screw driver in the middle of the caliper and apply the brakes, the pistons come out at the same rate and meet in the middle.

Looks like the position of the disc in the caliper is the issue, which would authenticate everyones view that the front forks are misaligned.

I also noticed the axle sticks out about 3mm on the right (if you are sitting on the bike)...?? and not flush with the forks??

btw

PS . is there a post on how to clean you calipers on here?

Thanks Lowrence, im a step closer.. but not sure how to fix it... how do i get the axle in further ? Do I need to remove thE wheel and start it all again?

Make sure that one is in the chamber before commencement of cleaning. Have a big sledge hammer near by for the final fine adjustments.

viewtopic.php?f=18&t=12626&p=144784&hilit=brembo#p144784

Link for brembo overhaul.

But to be honest it was a waste of time as per my first post.

I had this issue when I changed to a different brand of pads, dont ask me which I got though.

Everyone has to start somwhere and this will be a good thing for Davey when the problem is solved and he can look back and laugh at it.

ps. Thanks Turnip.. working on getting my gallery sorted

yip.. My concerns were right... if I move the axle in I can't even get my calliper on

Here are some pics

The only other possible thing I can think of is if you've had someone else work on your bike and they've somehow installed the wrong axel (ie too long). Pretty unlikely to find an axel that is the same diameter and that'll almost fit.

At this point you need to seek professional help or hopefully someone on this forum can stop by and help you sort it out.

Can't a access your photos big fella

should work now

Maybe I'm doing something wrong but it says no photos found in community photos...

Can see those pics now mate.
Can't see what the prob is though... Is that wear on your caliper itself in pic 12?

Yes it is.Caused by the disc rubbing..

had a closer look. The disc themselves are 40mm and the standard says 320mm?? The disk on the left hand side also looks flatter (less concaved) then the disc on the other side... I wonder if the disc has been replaced with the wrong item??

Where did you get this bike? Are you not the original owner? WTF?

Nope bought it from a kawasaki dealer..lol. I think they replaced one of them but with a slightly different one.. It looks identical but see 2 new pics, if i hold an allen key against the one disc it touches the tyre ( bad disc) the other side has a gap of 10mm..

https://picasaweb.google.com/1046861525 ... 9303544818

Also not sure if it's a 400mm disc.. both discs have a 4.0mm stamo on them? is that standard?

ANYONE HAVE A SPACE BRAKE DISC THEY WANT TO SELL

Please tell me it's my lucky day..

Will this fit?

http://www.ebay.co.uk/itm/Brembo-320mm- ... 43abce9b6e

Awesome-- but he wont sell to South Africa..lol.. Will have to get my sister to buy it (stays in uk) .. Really hope it's not damaged!! Just incase you guys know a cheap place to get discs.. how are the fleabay hong kong specials..

THANKS EVERYONE FOR ALL THE ADVICE AND HELP!! REALLY IS APPRECIATED!!

BTW - the 4.0 mm (or whatever) stamped on the discs are the wear limit. That is, the minimum thickness that the mfgr. considers them safe to continue to use. This would be normal to have this stamping - yes.

I'm guessing you got this already - the 320 mm reference is the outside diameter of the disc.

I can't tell by the pictures, but is it possible that one disc is mounted with the wrong side of the carrier towards the hub? IE it's the wrong way 'round?

Humm, I wonder if someone could have tweaked the rotor on the one side when they changed the tyre? I know for a fact that with the tyre off the rim, the rotor touches down before the edge of the rim. So, if someone set the rim down hard, or stacked something on top of it, he could have bent the rotor. That might even make it seem wider than it actually is supposed to be?

Usually when a carrier gets bent it's not uniform and you get a pulsing effect like a badly warped disc.

I have a fully morticed lockset that came with two differant knobs. If I post a picture of it on here could someone tell me which knob goes on the interior and which for the exterior.

I cannot believe what I just saw in those photos!

Turn the fooking disk around.

Next time post pictures first and ask questions later.

lol.. I wish it was than simple Lowrence.. The disc is concaved ( be it very little) in the correct direction.. So i doubt flipping it will make a difference, but will confirm that when i get home later. I cannot comment on how it got that way??? Will try do some investigation today!

The carrier is definitely bent. Whomever changed your tyres the last time really screwed you...probably dropped your wheel on the rotor (from a very high place) and tried to hide it from you.

Any luck finding new rotors? There are a couple breakers here in the US that have stock rotors for sale (about 1/2 price of new) and would probably ship them to you.

I'd ream the shop that screwed you and demand compensation...good luck with that. Worth a try.

Personally I'd take the opportunity to upgrade to Galfers, Braking orsome other aftermarket rotor/pad combo.

Are there meth labs in SA?

SA in Oz there are.
Most of our homemade drugs come form that state.

lol.. I have no idea how the disc ot that way.. but al least it's fixable. I have a bid on the 2nd hand disc on ebay, if i win the bid i'll fit that. Otherwise I was also thinking of upgrading to wave discs... but with christmas around the corner it will have to wait till next year...

Good luck Davey.



(BTW wave disc are not a upgrade.)

Thanks a mill Pete..

Not an upgrade? thought they were better than std one's?

Swept area and material are the 2 biggest factors with discs. The whole wave thing (on non dirt bikes) is just a fad / fashion thing.

Brembo are widely regarded as the biggest /best on motorcycle braking - they do not even have wavy discs in their product range. (Unless they are a VERY recent update.)

NO major players use wavey discs in WSB.


By the sounds of it you even imply you changeed because you didn't want to pay for brembo pads. I agree they are expensive but I bite the bullett because the feel and power combination is so good.

Not going to get into what's best, and while somewhat a function of cost, Galfer superbike wave rotors (and I have these on another bike) , Braketech ductile iron (I've owned these also), Braking, etc. plus some trick pads - are all pretty spendy. Application matters. A lot.

Sure, you can go nuts. Why not some ceramic rotors? Better throw a pair of those new Brembo monoblocks with the lithium alloy. Might as well fit up some Ohlins twin-tube SBK forks while at it. CF wheels - an absolute must! And lastly, a forged body Brembo master cylinder with the fold-away adjustable-from-the-left lever.

Not racing? Occasional trackday? Bike nighter (don't forget the Ti bolts!)? Street only? Factory stuff works great. Not merely good - but great. For the bike's intended uses, I've never experienced better functioning brakes out of the box. If the rules allowed, would I go racing for money with what the SD comes with? Probably not.

And I can stand the SD on its nose with two fingers with little effort - bone stock. I like both their progression and feel. I don't like super-grabby brakes around town (any 916/996 owners here?), or large-piston diameter master cylinders. I like feeding-in my brakes. And I like doing so as late as possible. So much shit on the road, can't afford anything too abrupt. Stock lever too. Longer = more leverage = more control resolution over lever distance moved. In fairness, I have huge hands, and Popeye forearms.

As I usually run my SuperDuke only at the less-fast courses in the region (and we have a couple of very fast courses here), I have never (!) experienced any fade. None. Not all day. Again - stock pads. And I know damn well I brake harder than most riders - one of the most effective ways to pass on the track. And I ain't no scrawny chicken-legged kid either - my brakes get worked.

As for "feel", a fairly subjective matter (although, "wooden" is pretty much "wooden" - we all know what that is). Have I used brakes that required less effort? You bet. And on one of those bikes with a one-finger-stoppie low-effort superbike setup, I've broken ribs stuffing the front end harder than there was traction for. What that setup lacked for me - was the ability to feed in braking as I like. Not making excuses, as going down was entirely my doing - but the setup just wasn't for me. Not for the average trail-brake-to-the-apex guy really (except maybe those that get paid to ride - where there would be more effective progression due to higher velocities).

Point: Can't argue with what some people clearly prefer in terms of performance, feel, progression, and whatever other criteria is important to them. They can justify their decisions with all sorts of test data and claims. Does the street rider benefit from off-the-shelf race technology? Maybe. I for one find the OEM setup excellent. Its all legitimate.

What matters beyond these subjective elements? Consistency. Knowing (without thinking) how your braking system is going to perform for a given condition, and that it does so the same every time - is the key to rider confidence. And my SuperDuke's brakes accomplish this for me perfectly, everywhere I use the bike, all the time. For others' setups, the right combination of pads, rotors, levers, master cylinders, calipers, and even wheels suits them better.

All good. But suggesting to a guy with what appears to be a fuckedup rotor, who clearly has yet to experience his SuperDuke brakes as they should function - to spend at least $500 (USD) to sort out his problems is a bit much IMO.

I agree, there is way more stuff to spend your cash on before upgrading your rotors.

Problem solved, fitted new rotor (brake disc) tonight. And all is sorted. Old one was flat as a pancake have no idea how it got that way, maybe manufacturer defect!! Thanks for all the advice, got there in the end.