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iceracer65
07-24-2006, 01:50 PM
its full of fluid and all bled out, but it wont hold pressure. i always have to pump it up.

if its just sitting there, it will hold pressure, but if i ride it, it looses its pressure...what gives?

Pappy
07-24-2006, 01:55 PM
any leaks in the caliper or master cylinder?

07-24-2006, 02:04 PM
i kinda have the same problem. ever since i brought the bike home, the rea brake has been weak. i thought it might have been that the fronts, being dual caliper, are that much better than the ones on my 400ex, so i didn't really think too much about it. then 2 weeks ago, i rode lonestar_r's 06 and his rear brake was much better than mine. I even got on the 400ex again and realized how much better those rear brakes are also.

my father and i have bled the line, we have had the caliper off and checked for leaks. there are none anywhere. the resi is completely full. i am thinking that maybe puting a "ss" braided line on the rear will help...

next step is the dealership before the warranty runs out...

iceracer65
07-24-2006, 02:09 PM
Originally posted by Pappy
any leaks in the caliper or master cylinder?

none that i can see, i put new fluid in, it hasnt used any.

could it be the parking brake adjuster?

Prey
07-24-2006, 02:12 PM
Originally posted by iceracer65
none that i can see, i put new fluid in, it hasnt used any.

could it be the parking brake adjuster?

is there any play on the pins, i have seen on other machines where these will wear, allow the caliper to move slightly which from a use stand point makes the brake feel real loose

iceracer65
07-24-2006, 02:15 PM
ill have to check it out.

thanks for the quick responses!

Prey
07-24-2006, 02:15 PM
Originally posted by Prey
is there any play on the pins, i have seen on other machines where these will wear, allow the caliper to move slightly which from a use stand point makes the brake feel real loose

also, if you are still using rubber lines, check to make sure they are not bulging, this will have the same feel as worn pins

iceracer65
07-24-2006, 02:28 PM
i dont think its the line. when i pump it up, it feels rock solid.

dunebuggie66
07-24-2006, 03:42 PM
there could be air in the lines. try and bleed them, and then see what happens.

roundsy
07-24-2006, 08:39 PM
having the same problem with my 450er right now, im going to try to take it in for warranty

kirtob
07-24-2006, 10:25 PM
Originally posted by iceracer65
its full of fluid and all bled out, but it wont hold pressure. i always have to pump it up.

if its just sitting there, it will hold pressure, but if i ride it, it looses its pressure...what gives?

Is your disk bent? If so when it spins it will move the pads farther away from the disk which pushed the cylinders in. Then you wil need to pump the pedal to push the cylinders back out.

check it

flattrack450
07-30-2006, 12:40 PM
i'm with him j, especially after your tumble in texas, i'd check that rotor. had the same problem with my street bike a few years back. bent rotor or cashed out rear line, i'd check those two to start.

btw, had a chance to asphalt that beast yet? sounds like there was only three quads at shawano for the nasmoto event...

tony

QuadRacer041
07-30-2006, 02:40 PM
bent disc ....... fo sho