Brake problem

[Auldlanzyn]

Hi, The front brakes on my 99RX busa are spongey all the time. Even when I pump the lever they are still soft. When I dont pull the lever for a few min when I go to pull it I have no brakes at all and have to pump the lever again.

I have new pads, clean free pistons, have bled the braided hoses until no air comes out, checked seals in master cylinder, back bled them and changed fluid all with no success.. Thanks

 

[nitrousjunkie]

Thats a classic Busa characteristic,put some braided lines on a HH rated pads and you'll be impressed.

 

[dadofthree]

It's possible that you have bent a rotor. Pump the brakes up and do not move the bike. After a few minutes check to see if the brakes are still up. If they remain pumped and you move the bike and lose brake, then pull each caliper inserting a flat piece of metal to mimic the rotor and determine which or if both rotors are bent. If you pump them up and without moving the bike lose brakes you have another issue. Just replaced a rotor for the same reasons.

 

[nitrousjunkie]

I see its a 99 so....you might be in need of a master Cylinder or caliper rebuild or replacement.

 

[Auldlanzyn]

Hi, Thanks.. I have earls braided hoses and HH sintered pads. The master cylinder seals seem fine but will replace anyway.. If the rotor was bent would I not experience shudder when braking? Although its a 99 RX its only just turnrd 9k miles. Would CRG levers with more adjustment help? Thanks for help.. Ill investigate further and report back..

 

[dadofthree]

I couldn't tell a difference. I had no shudder, plus I was already having to pump the brakes to get them to work. It was only one possiblity out of many. Good Luck.

 

[Auldlanzyn]

Hi, Master cylinder seals renewed. Solved problem. Many thanks for all your help...