So yesterday after coming home from a tire swap I nearly crashed into my garage door. I was so used to using just the front brake that I forgot about the back and saved it in time. The mechanic was kind enough to come over and power bleed my brakes because that's what we speculated it was. There was a bit of black fluid coming out of one caliper along with air bubbles from all 3 points. When all was said and done the brake pedal feel was even worse than before. He thinks that my seals may have deteriorated because of me topping it off with synthetic dot 3/4 fluid last year. This is just so strange to us because we both knew that the brakes were working perfectly before he did the swap.. Has this ever happened to anyone else?

 

he pushed the piston back in unevenly, and blew the seals?

 

ok. how would i prove that?

 

did you pump the brakes before you started riding?

thats very important

 

i wouldn't know but he did say my brake pedal felt mushy after he did the swap. he left them that way because he thought that was my preference..

 

If it was a single instance I would suspect brake knock back. Even if rotors are slightly malaligned you could still be suffering from knock back. is there pressure after a pump or two at the levers?

 

by pump does that simply mean applying pressure to the brake lever. if so then yes it but it was very little. the lever as of now no longer holds any pressure.

what is knock back?

 

Knockback is where a rotor is rotating out of specification(runout) and when it rotates, the rotor face pushes on the pads and the pads push the caliper pistons back into the caliper creating more travel... usually if you pump the brakes once or twice the pistons travel back out and finally make correct contact with the rotor, but if you pump the brakes (at the lever) and you never get pressure, you may have a master cylinder that has gone bad as fluid is slipping by the master cylinder piston, seals gone bad

 

i see. what i do know for sure is that my front brakes were biting hard prior to the swap. is this a common occurance for the seals to go out so early on a fairly new bike? i'm almost turning 10,000 miles.

 

Well 10k is not low mileage... But i get the gist of your question, yes it is fairly rare for this to be a manufacturing defect. I hate to say it but I would have to lay some blame at the feet of your tire changer... are you sure he assembled everything correctly? if he left out a bushing/spacer it can have this similar effect, some bikes even go as far as having asymmetrical spacers, left side is different than right

 

i'm certain that the spacers are symmetrical on the front and asy on the rear. so far total cost of the rebuild kit to service the master cylinder and calipers is going to be around $150..

i don't think i should have to pay the full cost of it. actually i don't think i should have to pay anything at all now that i think about it. but it's a lose/lose situation seeing how i can't prove it was his error. thanks anyway for the input mschu.

 

Check the brake rotors as well, its possible they could've been bent.

 

PROBLEM SOLVED.

after spending 4-5hrs of my sunday googling every possible scenario i found the solution on a stunter forum.. of all places

1. remove brake lever
2. remove lever plunger
3. insert similar size tool into plunger connector
4. simulate lever force by pushing tool inwards.

the reason of this being that the lever has insufficient clearance to restore pressure. i should have been a damn mechanic.. anyway, i hope this thread serves purpose to anyone who comes across the same problem. i wouldn't want them to go through what i nearly did.

 

Thanks for the update and answer. At least 90% of threads end with the OP only typing "Problem solved" without saying what it was.

 

some of you are already familiar with the issue of my front brake being near useless in this thread

afterwards i was able to restore pressure to the lever. and shortly afterwards i took the bike out for a quick ride in the city to enjoy what was left of the day. i didn't push the bike hard at all because once again i was still on brand new tires. the bike was handling normally and i really liked how easy it was to steer the front without a cupped tire. soon i was on my way back home on the highway.

moving along at 60mph with the flow of traffic with only a few vehicles pacing me i suddenly lose throttle response. i roll into it thinking it was just my head and watch my speedo slowly go down from 60, 58, 54 and so on. my throttle input was having no effect. i signal my intent to turn on to the shoulder and make an emergency swerve to avoid being rear ended from my rapid deceleration.

20, 13, 5.. 0.. then the bike dies

traffic is still flying by me and i can't get far enough off the shoulder because of the ditch. i keep my signal on and try to get the bike out of gear into neutral to start it.. i can't because the bike is in gear and won't move. i clutch it but i still can't get it to move.. i'm starting to get nervous as the sun goes down and i risk being hit by a car. i call my brother and tell him to come get me right away. i keep my helmet and bike on just in case while i wait for help. a short while later i turn my attention to the rear wheel and alternate between turning the spokes and upshifting while standing. it works, and i'm able to start the bike again. i'm just scratching my head wondering what just happened. i get the bike moving again but stayed under 25mph on the shoulder. less than a minute i later was on the off ramp. all too suddenly without warning the front wheel locks up and i'm fishtailing. i go down hard on my left side. my boot SAVED my left foot as i feel it strain against the weight of the bike coming straight down on my achilles. my left knee isn't so fortunate with just jeans and i feel the pain coming on excruciatingly.

bear with me as i'm just trying to document this before i forget little details. i call a knowledgable good friend and ask him what the hell just happened. he doesn't know. i tell him how i can unlock the front brakes and he tells me to open the bleeder nipples. i do so

edit: tired and in pain.. will finish later 1:07am

 

holy crap dude, please keep us informed!

I would also make an immediate phone call to the mechanic that serviced your bike and demand that he fix the issue. He undoubtably did something to the brakes knowingly or unknowingly. It could have cost you your life.

 

DO NOT admit to making any changes to the bike post tire change! this is horrible. the entire system need to be checked out before you do anything else.

 

i'm having trouble trying to start the bike. it started once after said crash but wouldn't start conventionally anymore whenever i turned off the bike. i was able to push start it on an incline and the motor ran fine. leaking oil but window still shows it holding a good amount. the battery is but 1 month old. starter motor sounds like it's struggling. does this have anything to do with the stator cover? that part took most of the impact.

 

this is why I won't let a mechanic, or a shop, or some idiot touch my bike. I thank my dad for teaching me how to figure **** out at a young age.

does the start even turn over, or does it just click? what kind of voltage does the battery have without a load?

 

the start was turning over a good bit after the crash but now it struggles and just clicks