Alright, some of you might remember near the end of the northern riding season, I put on new EBC X-disc contoured profile rotors, EBC HH pads, rebuilt the calipers cuz they were binding, dual SS front brake lines, and now I have rebuilt the master cylinder. I've bled this thing so many times I honestly don't think I can count that high; i've tried gravity bleeding, putting hoses into bottles and pumping the lever till i got such a forearm pump i couldn't squeeze my hand no more, had the wife help do the pump and hold, used a vacuum bleeder and I still don't have what i think should be a solid lever. I'm running pazzo shorties and I have the roll all the way out on six. DO NOT get me wrong, the bike stops really good, but not like it should. When i'm riding, the first time i pull the lever it's soft, then I grab it again and it's tighter; air right!?! I even tied the lever back and let it sit for DAYS, come out, release it, let it sit for a minute, grab it, it's tight, come back the next day and same ol', first squeeze soft, 2nd better. Also, on my shorties, if you were to ride my bike and grab the lever with the roll on like 1, you'd be pretty well screwed. Any ideas would be greatly appreciated.
Front Brake Problem
- Thread starter kjcili
- Start date
delbert
Registered
i have a simular problem with mine since i rebuilt the calipers some years ago , the problem seems to be that the pistons return too far so it takes the first squeeze of the lever to get the offending pistons to make contact with the pad , hence the travel . what the answer is i dont know , i have tried many things like you , good luck 
mike1180
Banned
Wardie posted this in another thread a while ago:
Shop manual says there's only one correct way to install them. They can be installed 180 degrees out. Check your seals to see if there’s a beveled edge on them. That's the side that goes towards the piston. Pistons should have to be "pushed" into the bore. They are very snug fit. Anything else and you have the seals in wrong and you won't build pressure. There's a shop manual hosted somewhere ask one of the guys to put you onto it. Hope this helps. Wardie
Shop manual says there's only one correct way to install them. They can be installed 180 degrees out. Check your seals to see if there’s a beveled edge on them. That's the side that goes towards the piston. Pistons should have to be "pushed" into the bore. They are very snug fit. Anything else and you have the seals in wrong and you won't build pressure. There's a shop manual hosted somewhere ask one of the guys to put you onto it. Hope this helps. Wardie
delbert
Registered
Okay. Its been awhile since input so I'll bring it up to speed. Took calipers all apart and all seals are crroect and same. Suzuki said that they eliminated the beveled edge, but I looked anyways just to make sure and my seals actually look pretty square. Put it all back together, same problem. Recently just purchased speed bleeders and tried that: I still have extended travel b4 I get a bite. Please keep in mind, my levers are also maxed out at 6. If I drop them to 1; just for trial reasons, the lever literally lays into grip. This is not right. I'm about to say f**k it and replace all hydraulics...
Brakes are like women, temperamental at times! My guess would be air trapped some place within the system.
I'd start by removing the mastercylinder from the bike. Then roll that puppy around and shake the sh-it out of it to dislodge any bubbles that may be trapped. Then pump the brakes up and bleed the system.
Your busa has no bleeder on the master cylinder which is a handicap. Any air trapped must be pushed through the lines to the caliper bleeders.
If nothing else works, remover the entire brake system from the bike in one piece. Slip something between the pads so they can't extend to far and hang the calipers up high with the master cylinder down low so any bubble trapped in the master cylinder can escape to the top ending up in the calipers. Pump some fluid through each side while in this position. Sometimes getting ALL the air out of a system takes some ingenuity.
If none of this makes a difference, the game is not over yet. Check for a slightly warped rotor. If a rotor is only slightly bent it can push the puck away from the disk just enough to cause excessive travel in the lever. If you have an extra wheel, install it and check the results.
The final step would be to replace the master cylinder. I have had brakes that just wouldn't keep a full lever and a fresh master cylinder was the trick. Not all master cylinders are the same and sometimes an overhaul doesn't give great results.
Good Luck! I feel your frustration. I've been there more than once.
I'd start by removing the mastercylinder from the bike. Then roll that puppy around and shake the sh-it out of it to dislodge any bubbles that may be trapped. Then pump the brakes up and bleed the system.
Your busa has no bleeder on the master cylinder which is a handicap. Any air trapped must be pushed through the lines to the caliper bleeders.
If nothing else works, remover the entire brake system from the bike in one piece. Slip something between the pads so they can't extend to far and hang the calipers up high with the master cylinder down low so any bubble trapped in the master cylinder can escape to the top ending up in the calipers. Pump some fluid through each side while in this position. Sometimes getting ALL the air out of a system takes some ingenuity.
If none of this makes a difference, the game is not over yet. Check for a slightly warped rotor. If a rotor is only slightly bent it can push the puck away from the disk just enough to cause excessive travel in the lever. If you have an extra wheel, install it and check the results.
The final step would be to replace the master cylinder. I have had brakes that just wouldn't keep a full lever and a fresh master cylinder was the trick. Not all master cylinders are the same and sometimes an overhaul doesn't give great results.
Good Luck! I feel your frustration. I've been there more than once.
dmallord
Registered
+1 "...If nothing else works, remover the entire brake system from the bike in one piece. Slip something between the pads so they can't extend to far and hang the calipers up high with the master cylinder down low so any bubble trapped in the master cylinder can escape to the top ending up in the calipers. Pump some fluid through each side while in this position. Sometimes getting ALL the air out of a system takes some ingenuity."
you shouldnt have to do this... but! it is very solid direction. some of the old ford rangers had a hydraulic clutch setup that had to be bled in a similar fashion.
hydraulics is possible because fluid doesnt compress. air in system = soft.
you shouldnt have to do this... but! it is very solid direction. some of the old ford rangers had a hydraulic clutch setup that had to be bled in a similar fashion.
hydraulics is possible because fluid doesnt compress. air in system = soft.
bigron
Registered
Even my braking went from okay to worse after i swapped my lines/pads and levers. I gravity bled the system like a thousand times and then even used mighty vac another 1000 times to bleed it. But my lever always had that "squishy" feel. After trying everything and getting bugged i just swapped my FT Tactical lever with my stock brake lever and Voila. The brake was biting hard and the lever was not squishy but crisp in its action. Strangely so but somehow my new lever was robbing me of braking feel and bite. i dont know why/how but i now have a silver brake lever and a black FP tactical clutch lever 
I have been leaning towards MC for a long time. Rotors are true. I actually had this problem before any repairs. Entire front brake hard parts have been replaced. Hydraulics rebuilt. Even found rotors weren't on the right side: if thats poss or makes sense, but they weren't!! One would actually hit cal, and after I swapped sides, it was fine. Torque to Suzuki specs.
And being a tech, seems to me, if you take the master and shake the bejesus out of it, you'll errate the fluid, unless you r referring to shaking it gingerly, but still shaking.
I also noticed; this weekend, that the mounting ears of one caliper has been ground down .030" compared to other.
I bled system for about 20 minutes per side with the speed bleeders and got absolutely no air.
I c cal's and MC in my future.
And being a tech, seems to me, if you take the master and shake the bejesus out of it, you'll errate the fluid, unless you r referring to shaking it gingerly, but still shaking.
I also noticed; this weekend, that the mounting ears of one caliper has been ground down .030" compared to other.
I bled system for about 20 minutes per side with the speed bleeders and got absolutely no air.
I c cal's and MC in my future.
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