front break squeeking

[125SMash]

mz 125sm

the front brake squeeked upon delivery.
the dealer said that it would go away with bikes use.

between the MSF training, licensing and registration i
havent been riding it that much, maybe a 24 hours in
total, but the squeeking has persisted, and if
anything, it became worse.
an observation i made is that when i roll off the
throttle to change gears, the bike instantly brakes.
Based on my experience with other motorcycles, i dont
think this is the engine braking.
Looking at the front disk closely i saw that on one
side the pad appears to be flush against the disk,
while on the other side there is minimal clearance.
Also the disk itself is worn much more on the side
where the pad seems to be 'too close.'
The braking off throttle is something i could get used
to if its just engine braking, but the noise is
constant, unbareable.

also when just walking the bike, it sqeeks if rolling straight forward, it squeeks a bit more when turning bars right, but squeeks much less or not at all if bars are turn all the way left, it also doenst squeek when ralling back.

dealer is too far so cant helpme, local bike shops turned me away on the basis of this being a brand other than they carry (i was planing to pay outside of warranty even), i just ordered parts and repair manual from my dealer, since the owner smanual does not provide any instructions aside from brake fluid gauging (not even refilling).

if anyone have any comments or suggestions on the topic please leave them here

[Dezmo]

your brakes should not drag, and while some brakes will squeal, they should only do it when applying them, not just rolling along. From the symtoms you describe, my guess is the caliper isnt aligned on the disc properly...its either assembled wrong, or another possibility is the front axle not being installed correctly, on some bikes it can be installed so that it puts a side load on the disc, and causes the dragging and squealing you describe. a misalignment of just a few mm is enough to cause probs.
A good way to check for disc/caliper misalignment is to take out the caliper mounting bolts and remove it from the disc...if it's difficult to remove, or if there is a gap between the mounting lugs on the caliper and the corresponding mounting lugs on the fork (with the caliper in place, just no bolts), then you have issues. The lugs should fit against each other, but without having to force the caliper into place.
Hope this helps...

[125SMash]

I brought the bike over to the dealer since then.
A mechanic over there told me that the disk brake was bent, "probably due to a disk lock being attached while the bike was moved" (never happened). Both the disk brake and the caliper carrier were replaced.

When i picked up the bike, it seemed to roll fine without any squeeling.
It was a middle of the winter with too much ice on the road so i had to transport the bike home. It didnt squeel during loading/unloading from the truck, nor being rolled away into storage.

When it was finally warm enough, i rolled the bike out and dammit, it was squeeling again, about as bad as on the day or original purchase/delivery.

I called the servicing mechanic, he was 'at a loss' and forwarded me to MZ-NA. They were very responsive, and service manager told me to try getting a brake spray cleaner, and ride it more. One thing that i was surprised about though. is he said that some brake dragging will always be there (?). The back brake never had any of such problems, but ok.
I got the spray, sure enough the squeeling stopped, but the 'hissing' continued, indicating brake drag, and by the end of the day the brake squeels again.

Thats the jist of my problem, and i will to pay the servicing dealer another visit to take care of this, but mean while i developed a 'theory' and wanted to know what you guys might have to say about it, and maybe even provide a quicker fix?

I have no reason to doubt that the parts were indeed replaced, so some kind of work has been done, and absence of squeeling on pick up confirms it. However this was right smack in the middle of winter, with colder temperatures. Could it be that the brake liquid in these hydrolic brakes contracted a little, and when the brakes were installed and 'adjusted' they were fine for that temp, but when i was able to roll out the bike for a ride, it was warmer about 50F. Could the change in temperatures cause the brake liquid to slightly expand and thus applying some pressure on the disc?

If this is the case, then perhaps it was the problem on delivery also, and when the selling dealer recommended me to rie it out, that put more strain on the dick brake and the heat caused it to warp simnilating damage from a diskbrake lock?

Only problem with this theory is that the back brake has non of such problems, so how come it wasnt affected?

Any insight / suggestions are highly appreciated.

[Dezmo]

I still think there is som caliper misaglinment, wether its the lugs on the fork, front wheel off-center, or the piston sticking in caliper itself.
the guy said the brake will drag some all the time, he's kinda right as the pads will touch the disc and make a hissing when rolled, but it shouldnt be bad enough to cause a squeal without the brakes being applied

[125SMash]

maybe.. hopefully the mechanic will figure it out the second time around..

what i'm still trying to figure out though, is if there is an alignmnet problem, why didnt it make noise on the day of the pick up?

is brake fluid affacted by temperatures like this?

[phlat65]

expansion of the fluid shold not cause a dragging problem if the fluid level in the master is correct. the master has a bladder that is vented to atmosphere on the top through the cap, so when the fluid "grows", it has space to fill, but moisture cannot get to the fluid. I have NEVER Warped a brake rotor from usage, and I have Abused the front on by Baggy! A bent rotor will push the puck back into the caliper and cause the front brake to need to be "pumped up" every time you apply it.

I would recomend you change the fluid first, and make sure the rotor is centeres in the caliper and carrier. you can change the fluid your self easily with a simple homemade tool. Get a 1-2 foot peice of clear hose that fits the bleeder fitting. next, punch a hole in the cap of a small clear bottle to fit the hose through. punch a smaller vent hole in the cap also. put the hose into the bottle so it is close to the bottom. attach the other end to the bleed fitting, so that the hose goes from the bleeder, goes upward and forms a loop, and into the bottle that is sitting on the ground. remove the master cylinder cap, open the bleed fitting 1/2 to 1 turn, and slowly pump the brake lever full strokes making sure to move it slowly. keep the master topped, DO NOT RUN IT DRY!!! do this untill 4-6 ozs has been through the system. the loop keeps the air bubble from the bleeder, and the small amount of fluid that goes back in will have no air. I have used this technique for years, and I change my fluid with every oil change!!

after you flush some fluid through, you can do the crack the bleeder pump the lever in and close the bleeder thing just to get any small air bubble out, but i never need to.

I recomend the Motul 600 Race fluid only. you will be amazed at the difference fluid will make.

[125SMash]

expansion of the fluid shold not cause a dragging problem if the fluid level in the master is correct. the master has a bladder that is vented to atmosphere on the top through the cap, so when the fluid "grows", it has space to fill, but moisture cannot get to the fluid. I have NEVER Warped a brake rotor from usage, and I have Abused the front on by Baggy! A bent rotor will push the puck back into the caliper and cause the front brake to need to be "pumped up" every time you apply it.

that settles that then.
so i'm back to square one as far as theories conserned.
i'm still dumbfounded as to why it didnt squeal on pick up, only to start squealing after a month of immobility, and then not go away with use..

anyway, thanks for the advice, i will follow some of the suggestions from the mz mechanic, and if that doesnt work i'll bring it back for servicing.
id love to mess around with it myself, but with a warranty still in tact i dont wnat to give them any opportunity to shift the blame on me if they cant fix something.
i was irritated enough when they hinted i bent the brake disk with a disk lock

[cat-tard]

The front brake on my Baghira was kinda spongy when we got it home... I went ahead and took the liberty of bleeding the fluid - good thing too because it looked more like molasses than DOT4 brake-fluid.

Further inspection revealed a floating-caliper that didn't seem to float much - disassembly, cleaning, and a re-greasing of the pins that secure the caliper to the bracket solved that. If yours is dragging one side of the rotor, I'd take a look at the pins that the caliper is designed to float on and see if cleaning and re-greasing would help - mine was a leftover 2002 model and the original grease was pretty old/dried-up.

[125SMash]

i think my situation is something similar..

except i alreday brought it to a dealer who diagnosed it as disk lock damage (which is completely out of the question).

supposedly he changed the caliper and the disk, a process which would have addressed any dirt issues.

of course its also possible he just sprayed the disk with brake cleaner, the noise was back the next time bike was used so


i love this bike, but i wish i spent more time riding it than trouble shooting