[Midnight6]

so im having a weird issue with my front brakes....

ive bled them multiple times, i have no air in the system. but no matter what i do they drag, and if i ride the bike around, they drag worse and worse the more i ride.

bike is a k6 600 stock master, crg lever, galfer superbike lines, stock calipers, galfer hh pads, stock rotors.

any help is greatly appricated

 

[Tripsrad83]

Sounds like seized pistons to me mate. Plus are you vacuum bleeding or conventional style?

 

[Midnight6]

its both sides that are dragging. ive tried conventional bleeding and vacuum bleeding

 

[BR Customs]

I have the same problem.The calipers arent stuck. But it will not stop rubbing. Everything is stock. (07 750)
Is the easiest way to see if the rotors are bent to just take them off and lay them flat?
What else can i look for? Im still searching..

 

[Tripsrad83]

Errrr.....must admit its a head scratcher. Because they're 4 pot slave cylinders it's quite possible one from each could well be seized if you store the bike outside and especially if you are in a coastal region. How new is the brake fluid you are using and are you using the correct DOT fluid?

 

[pinkfloydscorpio]

Could the CRG levers me pressing the push rod into the master cylinder? When I got a new rear brake lever, I had to down adjust the pushrod a couple threads because I wore through my rear pads in like 2,000 miles!

 

[BR Customs]

Does it sound like soemthing dot 3 would do? i dont know what was used before me the fluid did seem to have a film floating on it and it was low before i added some and the black rubber piece inside that im pretty sure goes in the cap was inside the fluid container in the shape of almost a cup.... Is there some way pressure would suck it down and make it like that or was it someone very smart?

 

[SuspensionGooRu]

Brakes

So have you tried to spin the front tire while its off the ground using a front and rear stand? Does it spin freely? Did you change the pads recently?

 

[PacificGSXR1000]

Does it sound like soemthing dot 3 would do? i dont know what was used before me the fluid did seem to have a film floating on it and it was low before i added some and the black rubber piece inside that im pretty sure goes in the cap was inside the fluid container in the shape of almost a cup.... Is there some way pressure would suck it down and make it like that or was it someone very smart?

I know the K6 is dot4 fluid. You might want to check what you are doing. Download the service manual. If the bike did end up with water in the lines and calipers then rust would start. Rust holds enough water to always have you brakes dragging after the water expands from heat. You can prety much tell its water when the dragging doesn't start until the fluids have warmed up from using the brakes enough to transfer heat into the fluid.

 

[Tripsrad83]

My advice would be to get the recommended dot liquid, buy it brand new and sealed, that old stuff sitting on a shelf in your shed will most likely drawn moisture in and contaminated the stuff, then vacuum bleed it.

 

[GSX550Guy]

my conversion with a 2007 master and 90 750 calipers is doing the same.....the more I ride the hotter they get and then they seize up on me...I have to open the bleeder at the lever to move again.

I have 2 problems that we've addressed and are currently fixing.

1. The older calipers on mine aren't allowing fluid to transfer back to the master due to rust particles in and around the pistons. I have purchased a rebuild kit for the calipers and will be replacing all of the rubber parts internally. I also got rid of the organic pads I was using and went with a semi metallic racing pad so that heat doesn't cause the excess pressure build up.

2. My master cylinder piston had a piece of rust stuck in the valve not allowing the fluid to flow back either. The master was soaked in some cleaner and then was flush and blown dry.

 

[ben600]

Seizing brakes - GSXR 600 K4

I'm having a similar problem with my GSXR 600 K4 track bike.

It's got HELL braided lines and race pads. It'll be fine for a lap or 2 but gradually firm up until there is NO travel on the lever at all! It's just rock hard, and they don't fully release when you let go of the lever. The problem comes and goes at will, no idea why.

I've blead with new DOT4 fluid, removed and cleaned pistons but they all look fine. But the problem is the same!

Any advice would be great. Cheers.

 

[USELESS^]

Bent Rotor

Hey I Had The Same Problem What You Guys Are Talking Bought.
Youse Dot 4 Brake Fluid. Its Hard To Tell If The Rotor Is Bent But Ive Found Its Normaley The Problem Before Anything Els.
Best Way Is To Take Your Front Rotors Off The Bike And Look At Them Real Close. Look At The Black Center On The Rotor Youle Finde A Slight Bend In It. Not On The Silver Part Where The Pads Conect. Even If Onley One Is Bent It Will Efect Your Brakes From Working.

 

[Boss Man]

For those of you complaining about brake drag, is it so bad that it is slowing the bike down or are they just in light contact?

With disc brakes the pads are always in contact with the rotors. Your wheel will spin freely when you take your calipers off, but it won't spin as freely when the calipers are on. This is completely normal.

Anyway, just thought I'd throw that out there.

 

[abuckler]

Any luck finding a solution to this problem?

 

[mattcfish]

I'm having the same problem on my custom project. I'm using 2011 Yamaha R6 calipers with a 2006 GSXR1000 radial MC. The calipers are in great shape and do not stick. I rebuilt the MC because it was leaking. I'm using brand new stainless braided lines. I bled the system and all was working well until the next afternoon. Pressure had built up in the system, the lever was rock hard and the front wheel was very hard to turn. I bled the calipers and all worked fine again. The next day the same problem. Seems to me that the flow back to the MC is being restricted somehow.
My theory is that a piece of crud I dislodged when rebuilding the MC is blocking the return passage, creating a one way valve. Pressure can go to the brakes by pushing the piece toward the brake line but the crud pushes back against the orifice when the pressure is released. The pressure is developing from expansion as the day gets warmer in the afternoon. Sound reasonable?
Any other theories or experience with this issue?

 

[Gsxr1000#116]

My theory is that you are dealing with a shit piece of equipment provided by suzuki. But I'm a little bias against stock suzuki components these days.
This happened to me and my outcome was a MC that deteriorated. Piston completely broke down. Brembo was kind enough to sell me a solution.
Hope you find the gremlin!

 

[rv6john]

I'm having the same problem on my custom project. I'm using 2011 Yamaha R6 calipers with a 2006 GSXR1000 radial MC. The calipers are in great shape and do not stick. I rebuilt the MC because it was leaking. I'm using brand new stainless braided lines. I bled the system and all was working well until the next afternoon. Pressure had built up in the system, the lever was rock hard and the front wheel was very hard to turn. I bled the calipers and all worked fine again. The next day the same problem. Seems to me that the flow back to the MC is being restricted somehow.
My theory is that a piece of crud I dislodged when rebuilding the MC is blocking the return passage, creating a one way valve. Pressure can go to the brakes by pushing the piece toward the brake line but the crud pushes back against the orifice when the pressure is released. The pressure is developing from expansion as the day gets warmer in the afternoon. Sound reasonable?
Any other theories or experience with this issue?

Sounds reasonable.

The more common cause is an incorrectly designed or improperly installed brake lever that does not allow the master cylinder piston to return all the way. It keeps the port to reservoir blocked.

BTW, welcome, do an intro in the "New riders and members" section and next time start a new thread with your problem instead of bringing back a 5+ year old post.

 

[bobl]

Sounds reasonable.

The more common cause is an incorrectly designed or improperly installed brake lever that does not allow the master cylinder piston to return all the way. It keeps the port to reservoir blocked.

BTW, welcome, do an intro in the "New riders and members" section and next time start a new thread with your problem instead of bringing back a 5+ year old post.

Easy way to tell, is take off the brake lever when it starts to lock up, instead of opening the bleeder. DO NOT ride it with this problem, or you may end up with a locked wheel at speed. 90% of these problems are incorrect or improperly installed brake levers.

 

[mattcfish]

I'll need to check the lever. It's new as well. Rebled the system and the problem has vanished for the moment. If the lever isn't returning all the way, can it be modified to open further? Maybe file a little off the stop.