CRF250L Rear Brake Master Cylinder Rebuild

I had this weird problem with my Honda #CRF250L that when I have not used the bike for about a week or more, the rear brake does not work. I found out that if I let a few brake fluid out either from the bleeder screw or the banjo bolt, at an instant it will work again. It has been like this for a while and is a hassle whenever I want to use the bike. I am working away from home so I seldom use the bike. I suspect the seal inside the master cylinder piston is getting bad. So I decided to rebuild the #rearbrake master cylinder and fix this issue once and for all.
The rebuild kit I used is not specific to Honda CRF250L but a generic part that will work with many different bikes. It is because many Honda motorcycles use the same Nissin 1/2" brake master cylinder and the internal parts are the same.

[@dblo01]

Very good demonstration. Thank you

[@DIYPhil]

hope it helps.

[@moskito5864]

OMfG this helped me A LOT ... i bow to the master and THANKS ... I thought i have to change some parts in the break cylinder on my CRF250L Hildegard, i am loving since 10 years. but it was just some AIR... damn thats the last thing i was thinking about ...sometimes its the little things . I just changed the break pads because i thought its the problem and there was oil missing. Today i learned that the plastic part wich ends in a spring on the break pedal is MOLTEN ... guess its the engine heat over the years. The other rear spring is gone...with the wind i guess, no idea for how long 🤣

[@kasule299h.d4]

Great Bro

[@DIYPhil]

Thanks. Hope it helps

[@Chris-uu3cp]

Great video, thanks for sharing!

[@DIYPhil]

Thanks for watching!

[@AdriftersLife]

Thx Bro u know a lot ! Thx for Sharing

[@DIYPhil]

Happy to help

[@robsonenduro3316]

great vid, same happened to my yamaha T7. After rebuild the problem didn't come back?

[@DIYPhil]

Hi. Fortunately, the problem did not come back. But I also later rebuild the brake calipers, so I thnk that it helps as well.

[@aldwinalmario2109]

Very informative sir.

[@DIYPhil]

Thanks. Hope it helps

[@kapetzy4672]

THANK YOU! 💯❤️

[@DIYPhil]

No problem!!

[@CatholicCrusader__30]

if the rubber washers are broken will the brake work? and which side do they do on?

[@DIYPhil]

Hi. It depends on how much worn or broken are the rubber seals. In my experience, my brakes will sometimes not work. If the rubbers are totally broken, then the brake will not work at all. There are 2 rubber seals. The upper rubber push the brake fluid to the caliper cylinder. The lower rubber prevents the fluid from leaking out the master cylinder.

[@ermanvar6300]

Thank you for sharing detailed video. There is one think that i need to know; is master cylinder kits different with front and rear? Or both same?

[@DIYPhil]

Different on the metal part but the 2 rubber seals on the piston are the same and interchangeable.

[@tonygarvey8148]

Good job

[@DIYPhil]

thanks. hope it helps

[@FloridaVolts]

will the cb500x wheels fit on the Crf250l? Without changing swingarm

[@DIYPhil]

no. the original CB500X rear wheel is too wide for the CRF swing arm

[@randolfllige9142]

Sir where did you source the parts? Thank you.

[@DIYPhil]

Hi. Here is Thailand, I bought the repair kit in the motorcycle parts shop in town. It is a generic kit not specific to Honda CRF250L and will work with many other models. Otherwise, you can get the parts from the Honda dealer.

[@skytechandgizmosmartinez7914]

Sir where did you buy the repair kit?

[@DIYPhil]

Hi. I bought it from the nearest motorcycle parts store in town. I brought the old parts, and they gave me this kit that matches the original. The one I bought is a generic kit, not specific to Honda CRF250L.

[@moskito5864]

btw, CAREFULL with the break fluid, it will remove colour where ever it drops. Break Fluid is better as every paint remover, try and wait for it for about 24h