[Mikesdad]

Hi all,
my son and i were replacing the rear tire of bike. after replacing we bled brakes as there was no pedal/pressure.
when you loosen axle though there is full pedal. Brakes have been thoroughly bled and now we are trying to figure out the next step. Any thoughts would be appreciated

 

[Schroeder]

Hi Mikesdad and welcome,
I'm afraid this forum is dedicated to the 4 stroke model of the CBR 250 (MC41) and not the two stroke version so there aren't many people here who are familiar with your bike but I'm sure someone here will know a bit about the brake issue.

 

[Mikesdad]

It is a four stroke, my apologies

 

[Schroeder]

Oops... When I looked up 2004 CBR 250 I accidentally read the specs of the cr250 which is a two stroke.😓
I didn't even know there was a 2004 CBR 250r.

 

[Mikesdad]

Nope you were right, just asked my son and it was supposed to be a crf 250r

 

[onebohemian]

If you pushed the brake pad pistons back into the caliber when you removed the wheel, you have to pump the pedal a handful of times when the wheel is replaced to move the pistons back out to engage the pads to the disc. It isn’t clear how you bled the brakes before the pads were engaged back against the pads—did you use a mityvac or pump and hold the pedal to try and force fluid through? I suspect that when you loosen the axle, the wheel and disc may be leaning one way or the other enough to be causing one pad to press against the disc, giving the impression of full pedal. I think I would tighten everything back up and then repeatedly pump the pedal while your son watches the pads to see if the pistons push them against the disc at all. Hopefully they do, and then once snug, I would then rebleed the brakes if the pedal does not get firm enough. Maybe you introduced some air when you bled it the first time.

Good luck,
Mark
Minneapolis

 

[Mikesdad]

If you pushed the brake pad pistons back into the caliber when you removed the wheel, you have to pump the pedal a handful of times when the wheel is replaced to move the pistons back out to engage the pads to the disc. It isn’t clear how you bled the brakes before the pads were engaged back against the pads—did you use a mityvac or pump and hold the pedal to try and force fluid through? I suspect that when you loosen the axle, the wheel and disc may be leaning one way or the other enough to be causing one pad to press against the disc, giving the impression of full pedal. I think I would tighten everything back up and then repeatedly pump the pedal while your son watches the pads to see if the pistons push them against the disc at all. Hopefully they do, and then once snug, I would then rebleed the brakes if the pedal does not get firm enough. Maybe you introduced some air when you bled it the first time.

Good luck,
Mark
Minneapolis

Thanks Mark,
we ended up finding that one of the bolts on either side of the axle mount that keeps the axle true had stripped out and had the tire off by a fraction causing pads to wear improperly. We ordered new pads and will install when we receive them. Thanks for your input it helped us further diagnose the issue!

 

[DannoXYZ]

Note that axle-adjusters are only used as visual guide, they actually don't take any load at all. Your wheel moved because the actual axle-nut was too loose. Use torque-wrench and 3-ft handle-extension to tighten axle-nut to spec. At that point you can actually remove axle-adjusters completely and wheel should stay in place.

 

[Niyaz]

Hi all,
my son and i were replacing the rear tire of bike. after replacing we bled brakes as there was no pedal/pressure.
when you loosen axle though there is full pedal. Brakes have been thoroughly bled and now we are trying to figure out the next step. Any thoughts would be appreciated

pump ka problem hai pump kholke us mai uper se apko oil dalna hai to lagne lagega break