Hi Guys,
I have an 08 WR 250. The problem I have is the rear brakes fade, to the point they're gone after only a couple of miles, like 3!! I've changed the fluid, changed to a vented disc, and they're still garbage. Any tricks out there??
Thanks.
Rear Brakes fade after short use.
Started by 2stroke81, Jan 17 2012 04:05 PM
12 replies to this topic
Posted 17 January 2012 - 04:05 PM
Hi Guys,
I have an 08 WR 250. The problem I have is the rear brakes fade, to the point they're gone after only a couple of miles, like 3!! I've changed the fluid, changed to a vented disc, and they're still garbage. Any tricks out there??
Thanks.
Posted 17 January 2012 - 06:57 PM
OK, First of all rebuild the master cylinder. Probably the diaphram is bad. Use Motul RBF600 brake fluid. Use Moose or DP brake pads. I use a heavier than stock brake petal spring so I "FEEL" the brake before it starts dragging. ALSO, go to a solid brake rotor. The rotor serves as a heat sink and draws heat away from caliper. A vented rotor doesn't pull as much heat from the pads because of reduced contact area.
Posted 19 January 2012 - 08:43 AM
Here is what I have done On my 250 I put on a vented rotor from the 2002 CR 250 and then used Motul racing brake fluid
for me the vented rotor worked better.
BUT for a complet cure I got a one off custom built rear caliper mount which was made by Zip Ty Racing Now with the new mount I can use a bigger rear rotor the same size as all the other Husky use be it a 4 stroke or a Cr 125 Only the Wr 250/300 uses the small rear rotor Now the rear brakes works great
The only problem is Zip Ty racing does not have any more and I do not know if he will make any more
Maybe if more people want then . All I know is now it WORKS
for me the vented rotor worked better.
BUT for a complet cure I got a one off custom built rear caliper mount which was made by Zip Ty Racing Now with the new mount I can use a bigger rear rotor the same size as all the other Husky use be it a 4 stroke or a Cr 125 Only the Wr 250/300 uses the small rear rotor Now the rear brakes works great
The only problem is Zip Ty racing does not have any more and I do not know if he will make any more
Maybe if more people want then . All I know is now it WORKS
Posted 19 January 2012 - 09:20 AM
Sounds like a simple problem of over heating.
The fluid gets hot and can actually boil thus creating air bubbles which results in fade to loss of braking.
Do the Motul 600 fluid. Also look at running different brake pads. Many pads are not designed to get hot hot and a similar result happens here as well...fade.
Rider use or mis-use can be a major factor as well. Depends on what you are doing with the brake.
The fluid gets hot and can actually boil thus creating air bubbles which results in fade to loss of braking.
Do the Motul 600 fluid. Also look at running different brake pads. Many pads are not designed to get hot hot and a similar result happens here as well...fade.
Rider use or mis-use can be a major factor as well. Depends on what you are doing with the brake.
Posted 19 January 2012 - 12:23 PM
The one big problem is all the Husky come with a much larger rear break even the CR /WR 125 But the heavier WR 250/300
comes with a small rear rotor
All the rear rotors inter change from like 2006 to 2012 125 thru the 511 but the 250/300 is smaller and solid
comes with a small rear rotor
All the rear rotors inter change from like 2006 to 2012 125 thru the 511 but the 250/300 is smaller and solid
Posted 19 January 2012 - 12:32 PM
I would verify that you pads are not dragging and overheating the brake fluid. Make sure that the caliper floats on it's pins or it will cause the pad(s) to drag heavily.
Posted 19 January 2012 - 03:29 PM
Ok so here's what I've done. I had a solid rear disc on the bike to start with then changed to the vented, as it's suppose to dissapate heat better. If the bike was on the stand and I looked at it, the rear brakes would go. LOL. I changed the fluid, with Bel-Ray, use ebc pads with a modified ceremic backer. I do brake slide most corners. The brake pedal is set a little low, so I don't drag it and it's free as a bird on the pins, (which were new in Sept as I wondered that myself). I've been riding/racing for 25+ years and never have had such bad rear brakes. I've owned all and raced all, but never have had problems before.
I'm going to chage the fluid again with Motul 600. Does anyone know if there is a heat dissapator thingy that bolt to the caliper to help with this??
Thanks.
I'm going to chage the fluid again with Motul 600. Does anyone know if there is a heat dissapator thingy that bolt to the caliper to help with this??
Thanks.
Posted 19 January 2012 - 06:05 PM
Use the DP or Moose pads as they have ceramics on back of the pads to help prevent heat transfer. The Moose pads are same as DP but have double thickness of the ceramics.
Dick Burleson (8 time National Enduro Champion and Mechnical Engineer) explained to me why the solid rotor is better. A vented rotor is mainly for weight ,not cooling. BUT, it will run cooler than a solid BECAUSE there is less heat transfer from the pads to the rotor due to less contact area. By running a solid rotor the the rotor absorbs the heat (because of increased contact area )from the pads and away from the caliper. Thus the Caliper runs cooler and less chance of boiling the fluid. It works. I have not had any boiling problems since using solid rotors. You also have the added benefit of longer lasting pads.
Dick Burleson (8 time National Enduro Champion and Mechnical Engineer) explained to me why the solid rotor is better. A vented rotor is mainly for weight ,not cooling. BUT, it will run cooler than a solid BECAUSE there is less heat transfer from the pads to the rotor due to less contact area. By running a solid rotor the the rotor absorbs the heat (because of increased contact area )from the pads and away from the caliper. Thus the Caliper runs cooler and less chance of boiling the fluid. It works. I have not had any boiling problems since using solid rotors. You also have the added benefit of longer lasting pads.
Posted 20 January 2012 - 06:06 AM
I'm running Motul RBF 660 without any problems.
You also might want to check to see if you have the return spring at the rear break pedal.... sometimes they're not there or have fallen or broken off and that will cause problems.
Oh ya... bleed your rear break and only fill the break reservoir 1/3 to 1/2 way up... if you over fill the reservoir it will cause the break fluit to expand causing the break pads to make contact and drag with the rotor.
You also might want to check to see if you have the return spring at the rear break pedal.... sometimes they're not there or have fallen or broken off and that will cause problems.
Oh ya... bleed your rear break and only fill the break reservoir 1/3 to 1/2 way up... if you over fill the reservoir it will cause the break fluit to expand causing the break pads to make contact and drag with the rotor.
Posted 20 January 2012 - 11:32 PM
HuskyRips, on 20 January 2012 - 06:06 AM, said:
I'm running Motul RBF 660 without any problems.
You also might want to check to see if you have the return spring at the rear break pedal.... sometimes they're not there or have fallen or broken off and that will cause problems.
Oh ya... bleed your rear break and only fill the break reservoir 1/3 to 1/2 way up... if you over fill the reservoir it will cause the break fluit to expand causing the break pads to make contact and drag with the rotor.
You also might want to check to see if you have the return spring at the rear break pedal.... sometimes they're not there or have fallen or broken off and that will cause problems.
Oh ya... bleed your rear break and only fill the break reservoir 1/3 to 1/2 way up... if you over fill the reservoir it will cause the break fluit to expand causing the break pads to make contact and drag with the rotor.
ESPECIALLY bleed the brake once you have replaced your pads. Too many have bled their brakes several times before replacing pads and once you have replaced your pads , now you have too much fluid in the system.
Posted 21 January 2012 - 04:35 AM
Dwight_Rudder, on 20 January 2012 - 11:32 PM, said:
ESPECIALLY bleed the brake once you have replaced your pads. Too many have bled their brakes several times before replacing pads and once you have replaced your pads , now you have too much fluid in the system.
[size=4][font=arial,helvetica,sans-serif]X2
[/font][/size][size=4][font=arial,helvetica,sans-serif]And when you replace your pad... make sure the rear break reservoir is only 1/3 to 1/2 full... DO NOT OVER FILL!!!... if anything bring a small bottle of break fluid with you in your tool bag if you have to add or bleed on the trail.[/font][/size]
Posted 15 February 2012 - 10:53 AM
RBF660!!(its the S&*T) EBC Reds or other similar material pads, well set up for personal feel and properly serviced (as stated wisely and expertly above) and use your choice any oem config of rotor solid or vented (DB is pretty good voice to follow).
The EBC reds (pad material) seem to be very well insulated from heat transfer into the back plate/to piston/to fluid/to caliper (the sintered metal pads are not a good insulator, they transfer lots of heat). Whille still working well.
My personal (ammie rider/racer) machine is over and above spec with a Slavens Racing in line rear caliper heat sink and a ZipTy Racing reservior extender.(RBF660 and EBC Reds/without the back plate insulator pad per EBC) in use with the OEM (Braking) disc and Brembo caliper.
EBC Reds were recommended to me here on T Talk and other sites, thanks for that one!!
The EBC reds (pad material) seem to be very well insulated from heat transfer into the back plate/to piston/to fluid/to caliper (the sintered metal pads are not a good insulator, they transfer lots of heat). Whille still working well.
My personal (ammie rider/racer) machine is over and above spec with a Slavens Racing in line rear caliper heat sink and a ZipTy Racing reservior extender.(RBF660 and EBC Reds/without the back plate insulator pad per EBC) in use with the OEM (Braking) disc and Brembo caliper.
EBC Reds were recommended to me here on T Talk and other sites, thanks for that one!!
