Hi there, I recently got a 2004 Gas gas txt 280 and there is a problem with it. I went out on it and it went great but, after 5 mins of riding the front tyre locked and caused me to crash. Im not sure what the problem could be but my guess is the brake fluid. any advice would be appreciated, thanks.

Check if its the brake or the wheel bearings which are stopping the wheel. Then go from there.

My guess is the front disc or wheel is out of alignment causing extra friction. The rubbing will cause the disc and brakes to heat up expanding the hydraulic fluid and lock up the brakes. The front wheel should spin freely. Also check for worn pads.

How do i go about fixing it? or should I take it back to the garage so they can fix it?

It also could be the brake itself. I had a similar experience with the back brake after buying an old bike. One of the pistons was getting stuck on causing friction, heat and lockup. Take off the front brake, take apart, and see if you can push the pistons freely. If you can't then you need to remove and inspect the pistons. Use compressed air to pop them out, but be careful and put a rag over the pistons because they can shoot out like a cannon! You can try to replace the seals or buy a rebuild kit, but if the cylinder is corroded you need a whole new brake.

Hi make sure you have some free play on the brake lever, if you hav'nt it might stop the fluid returning to the reservoir and cause the pads to rub and over heat.try releasing the screw and lock nut on the lever.

TLTEL

Hi make sure you have some free play on the brake lever, if you hav'nt it might stop the fluid returning to the reservoir and cause the pads to rub and over heat.try releasing the screw and lock nut on the lever.

TLTEL

That's my guess also. I can think of few things that would totally lock up a brake, cause drag maybe, but not lock it up. If the adjustment is in too far, it's a closed system and that would lock the brake when the fluid expands with heat. If that's the case, I would think it would release (and probably drag some) when the fluid cools off.

The lack of freeplay is a very common problem with riders that come from cable systems to hydraulic.

Jon

My front brakes are still causing friction (2005 TXT280 pro) after cleaning the caliper and replacing one of the pistons & seal that wasn't retracting all the way. With bike on the stand and spin the wheel hard I can get about 4 rotations.Is that acceptable?

I inspected the disc. It does not float at all. Not side to side or in rotation of tire.

Does the amount of brake fluid have effect?

Should the reservoir be completely full?

If there is air in the sytem would the pads not retract fully?

I would assume if the front tire does not rotate freely it would have a tendancy to skate and have a effect on the rear tire traction?

Not completely full, there has to be room for the fluid to expand.