Alrighty, first post here, first trials bike in the garage! It's a 2000 gas gas txt 280. So far the only problem I know about is the back brake feels like it's dragging/bound-up a bit. Where do I start with diagnosing/fixing this issue? I plan to flush all the fluids before riding but I'm a bit stumped on what could be causing the brake to bind. Anyone have any ideas?

Not enough / any slack at the pedal. Brake is dragging all the time causing it to heat up and lock on would be my guess.

22 minutes ago, b40rt said:

Not enough / any slack at the pedal. Brake is dragging all the time causing it to heat up and lock on would be my guess.

Thanks, that was my guess too, just not sure why anyone would've adjusted it to not have any slack, or how it would've gotten that way. I took a look at the adjuster and fiddled with it a bit. I assume I need to loosen the lock nut, then turn the threaded shaft thing in to the pedal assembly to effectively make it shorter? Is there a spot to grip it to turn it or if I take the pedal off, will it be easier?

Not sure with your bike, but effectively when you push the pedal it shouldn't immediately move the piston.

I think I made some progress. Pulled the back wheel and flushed/bled the brake. It looked as if the pistons weren't moving at all. Once I got it bled as best I could, I just held the pedal down for a few minutes and one of the pistons started to move. I worked that one in and out and then another eventually started moving. I'm going to guess all 4 should move, and that I'm half way there? Put the wheel back on and it did seem to spin more freely. Going to ride it around the yard a bit tomorrow and see if the other 2 pistons start working or not.

 

Edit to note: The pedal basically "goes to the floor" before starting to move the pistons at all. The pistons that do move, do so fairly slowly.

Edited July 25, 20188 yr by J5k
additions

On ‎25‎/‎07‎/‎2018 at 1:56 AM, J5k said:

I think I made some progress. Pulled the back wheel and flushed/bled the brake. It looked as if the pistons weren't moving at all. Once I got it bled as best I could, I just held the pedal down for a few minutes and one of the pistons started to move. I worked that one in and out and then another eventually started moving. I'm going to guess all 4 should move, and that I'm half way there? Put the wheel back on and it did seem to spin more freely. Going to ride it around the yard a bit tomorrow and see if the other 2 pistons start working or not.

 

Edit to note: The pedal basically "goes to the floor" before starting to move the pistons at all. The pistons that do move, do so fairly slowly.

Clamp the pistons   that move once you have pushed them as far back into their cylinders as they will go ..... now when you operate the pedal you may get the two seized ones to start moving ..........if your pedal 'goes to the floor' then your system has air in it probably caused by a worn seal on the piston or a worn bore in the master cylinder that is if you have bled the system using the correct method.and it still is not a firm pedal.

Thanks, I was trying to hold them back but not sure I have a clamp I can get in there to get the job done. I did try to flush/bleed but not sure I’ve gotten all the air out. I rode it a bit yesterday, and will try bleeding again tonight.