Front brake is on all the time

[Larsa]

The brake pads don’t let go when I spin the front wheel.
When I spin the wheel it stops after one lap.
I have tested all I can think of. It is not too much brake fluid.
I can also see that the front disk is not sitting 100% in the centre.

I have similar problems on the rear brake but not as much.
EC 300 -07

 

[blitz11]

Does it stop in the same location every time? Bent rotor(s)? have you put a dial indicator on the rotor? Did you measure runout?

If you pull the caliper off, can you depress the brake piston? Is it stuck?

The master cylinder acts to both push the piston out (positive pressure) and withdraw the piston (negative pressure/vacuum). (That's why you have the return spring). If the piston doesn't move freely, the negative pressure will be insufficient to draw the piston back a bit.

 

[Rick]

You might want to try bleeding the brakes. You can also remove the pads and check to make sure the front wheel make more than one lap. Check to see if the rotor is damaged. If not, you better look at wheel bearning/spacers/seals and that the axle is installed properly and torqued.

 

[Larsa]

Still don't find the problem

I can press on the brake with my hands so that the brake cylinder depress.
When the brake and the wheel are installed on the bike. Then the wheel spinns perfect. After that I pump the brake handle and brake the front wheel.
Then the brake is on again and the wheel on spinns one lap.
I have clean every thing and oil the brake cylinder and the pad pinn.
And there are no mark on the pad pinn.

 

[gasgasman]

Larsa. How's it going?

You may have a restriction in the front brake hose. Sometimes a rock may hit the hose and cause internal damage that you can't see.
The internal teflon liner may have a section broken off that acts like a one way valve.

Try this:
Apply the brake until it acts up.
Loosen the brake hose at the caliper. If the problem goes away, then the hose is restricted.

If the brake is still locked up, then the caliper is sticking.

 

[gasgasman]

Larsa.
By the way, Mark Tracy is getting a 2009 Husaberg 450.

 

[Larsa]

Now it works

Girard

I did like your advisory and when I loosen the hose brake bolt.
And the brake was still on. Then I swap the caliper from my son Yamaha YZ 125 than got the same Nissin caliper as GasGas. On the GasGas caliper support then I got it to work so something must be wrong inside the caliper. But I will fix this later for this week end I am going to race in the biggest enduro race in the world “Gotland Grand National” 2300 at the starting line for 3 hours http://www.gotlandgrandnational.com/
http://www.gotlandgrandnational.com/ggn2008/ggn_invitation_rules_2008.html
Many thanks Girard you are great as always
I know that Mark has order a Husaberg -2009 450 and I think that bike looks cool.
I did not like the old Husberg it look very old but the -09 is a winner.
Do you know if Mark has got the Husa yet.

 

[Larsa]

I did not find any problems in the caliper

I took the caliper apart and clean it but I did not find anything wrong.
So now I have the YZ caliper on my GasGas working and the GasGas caliper on the YZ 125cc working.