PDA

View Full Version : Rear brake


dads400ex
08-19-2007, 09:38 AM
Give me some ideas guys as to what to look for on my '05 I have excessive travel in the rear brake pedal before it creates pressure. I have bleed and rebleed the system, adjusted the pedal and checked to see if the caliper is moving freely and everything looks good. So help me out guys.
killroy
08-19-2007, 11:09 AM
keep bleeding...get new brake pads
TRX450RACER174
08-19-2007, 03:28 PM
Bleed it more or you have a bad brake line maybe.
hendershot106
08-20-2007, 01:03 PM
check your brake pad width--- they are probably SHOT!!
hendershot106
08-20-2007, 01:03 PM
check your brake pad width--- they are probably SHOT!!
dads400ex
08-20-2007, 03:35 PM
Pads look to be near new.
XXXRACER165
08-20-2007, 04:21 PM
My dad has this same problem on his 450R, we bled a whole bottle through the thing and the pads are new!
Sjorge450R
08-20-2007, 06:42 PM
make sure that the master cylinder is tightened to the frame. I forgot to put one bolt in and the cylinder itself was moving. thats what my problem was.
chris46250r
08-20-2007, 07:53 PM
A slightly bent rotor will cause this also. The bent rotor will push the pads back further than they need to be, causing you to push further down on the pedal to stop.
dads400ex
08-20-2007, 08:13 PM
Originally posted by chris46250r
A slightly bent rotor will cause this also. The bent rotor will push the pads back further than they need to be, causing you to push further down on the pedal to stop.

Even sitting still, I am not rejecting this as I am looking for all ideas. Just asking. This has me stumped.
chris46250r
08-20-2007, 08:21 PM
Well, no it shouldn't if you are not moving.
dads400ex
08-30-2007, 05:58 PM
Bringing this back up. Somebody has to have run into this problem on here. I took the master cylinder apart and looked at it and it looks good, no tears in the cups and the cylinder bore is clean and free of grooves. Replaced the rear brake line and rebleed the system and the pedal is still spongy. I have since rebleed and still have a spongy pedal. My son rides a same year 450r and the rear brake feel is completly different it is very solid and so are the other quads that I have so I have something to go by.
ss440ex
08-30-2007, 06:22 PM
Any damage to the brake line/hose?
Any swelling, distorsion....
Watch line when pumping the peddle.
Keep us updated,
Good luck.
dads400ex
08-30-2007, 07:42 PM
Watched the line, no swelling or distortion. Still trying to figure this out.
ESrider
08-31-2007, 08:58 AM
Try removing the line and the black plastic piece that attaches to the master cylinder and clean it out really well. I've seen saveral bikes get a piece of dirt or sand in there and cause this problem. If your that far you might also want to disassemble the master cylinder and clean it out as well.
dads400ex
08-31-2007, 03:22 PM
ESrider, already did that but thanks for the suggestion.
08-31-2007, 03:30 PM
i am experiencing this with my 06...i went to a braided line...it helped, but the rear brake is still worse than my wifes 400ex...
08-31-2007, 04:48 PM
I would get a vacuum pump and bleed it with that. You can also try to bleed it at the master cylinder, by pumping it an cracking loose the bolt that holds the line to the master cylinder.