Front Brake Pressure Problem

[ldryder]

I changed my front tire today and when I put the calipers back in place, I squeezed the brake lever several times to put pressure back into the system.

Everything was fine until I rode the bike. Once the bike was moving, the pressure in the front brake was gone and the bike didn't stop until the lever almost pressed against the handgrip. I found that I could squeeze the lever a few times and return everything to normal but as soon as I rode a bit farther... the pressure disappeared again.

If I squeezed the lever a few times when stopped at a light or when parked the pressure remains. However, as soon as I move, the pressure disappears again.

I've never experienced anything like this. Has anyone else?

 

[FlatlandBusa]

Sounds like your rotor(s) got bent and are pushing the brake pads back, creating an air gap that you must take up by pumping the brake lever.

 

[Adam G]

That or air in lines. I would bleed them for sure. If you are going to bleed them might as well bleed all of the old fluid through and replace with new. Worth a try. Rotor inspection sounds like a good idea too.

 

[ldryder]

I would approximate the side-to-side movement of the left rotor to be approximately .2mm. I do not feel pulsing in the brake.

I change my tires with a Cycle Hill changer and MoJo lever. Yesterday, I was having a lot of trouble balancing the front tire and put it back on the Cycle Hill several times in order to turn the tire on the wheel. I don't remember hitting the rotor against anything but the left side rotor does have some side-to-side movement while the right side rotor does not.

I'm going to replace the rotor and I'm going to open the brake reservoir, tie the lever to the grip and see if an air bubble will come out of the lines because I know that the bike will not build pressure with air in the lines but I also know that the lever will be soft whether I'm moving or not.

 

[FlatlandBusa]

Can you raise the front of the bike up and spin the wheel to replicate the problem? Also make sure the axle spacer for the front axle is in the correct location.
It would be nice to be sure before spending $$$ on a rotor.

 

[ldryder]

Yes, I did just that.

Thankfully, I called Justin at Honda East and found out that the 2013 rotors are different than the earlier years and appear to be considerably less expensive too. I ordered one and will stop by the store and pick it up on Friday. If that doesn't solve the problem... at least I'll have a spare rotor in the garage.

 

[ldryder]

PROBLEM SOLVED!!!

I installed the new brake rotor and everything works perfectly. It appears that the rotor carriers on the 2013 are a bit on the fragile side. At least they only cost about 1/2 the price of the previous years part.

 

[Adam G]

You don't find that very often. Price on parts going down, who'd a thunk?

 

[FlatlandBusa]

PROBLEM SOLVED!!!

I installed the new brake rotor and everything works perfectly. It appears that the rotor carriers on the 2013 are a bit on the fragile side. At least they only cost about 1/2 the price of the previous years part.

I wonder if the newer rotor would fit in the 2008-2012 Busa's?

 

[ldryder]

You don't find that very often. Price on parts going down, who'd a thunk?

I was so surprised that I called Justin back and asked him to check the part number and price a second time. BTW... the part number for the 2013 front rotor is different than the earlier years.