2014 RM-Z250, Free play in front brake piston?

Stylaren
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Stylaren
Hello!

Recently i notice that my front brake doesn't feels like it did before. I can almost pull the whole lever to the handlebar and I have a play before i feel that the brake applies. It's like the piston travel for like 5mm before i can feel brake power. Shouldn't it just be to lay a finger over the brake to feel difference?

Any suggestion how i can solve this? I have tried many times to bleed the front brake without any noticeably difference.

Thank in advance.

// Stylaren

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BenG
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BenG 6/14/2018 3:15pm
6/14/2018 3:15pm
Replace the brake cable.
Paw Paw 271
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Paw Paw 271 6/14/2018 4:02pm
6/14/2018 4:02pm
Check your front disk. If it is not running true it will push the piston back further than normal and then when applied you will have a dead space.

Paw Paw
Stylaren
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Stylaren 6/15/2018 3:08am
6/15/2018 3:08am
BenG wrote:
Replace the brake cable.
Thank you Beng for your reply!

Could you please explain why you think it's the brake cable? I just wan't to understand what could be wrong. Smile
kb228
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kb228 6/15/2018 3:13am
6/15/2018 3:13am
Assuming youve already visually checked your pads and know you dont have air in the lines... x2 on the brake line.

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BenG
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BenG 6/15/2018 3:27am
6/15/2018 3:27am
Stylaren wrote:
Thank you Beng for your reply! Could you please explain why you think it's the brake cable? I just wan't to understand what could be wrong...
Thank you Beng for your reply!

Could you please explain why you think it's the brake cable? I just wan't to understand what could be wrong. Smile
If the cable is old it can stretch like a balloon when you apply pressure and not feel solid.
Stylaren
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Stylaren 6/15/2018 3:40am
6/15/2018 3:40am
kb228 wrote:
Assuming youve already visually checked your pads and know you dont have air in the lines... x2 on the brake line.
Thank you kb228!

New pads since one hour back, did bleed the brake along with the installation. Could you explain why you think it's the brake line?
kb228
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kb228 6/15/2018 6:13am
6/15/2018 6:13am Edited Date/Time 6/15/2018 6:24am
kb228 wrote:
Assuming youve already visually checked your pads and know you dont have air in the lines... x2 on the brake line.
Stylaren wrote:
Thank you kb228! New pads since one hour back, did bleed the brake along with the installation. Could you explain why you think it's the brake...
Thank you kb228!

New pads since one hour back, did bleed the brake along with the installation. Could you explain why you think it's the brake line?
Over time they wear out and are able to sortof expand more when you apply the brake. Its the same reason steel lines provide better braking. They dont expand like a rubber line would. so when a line is worn out, instead of all your braking force being applied to the pistons, it will be applied to the pistons AND walls of the brake line. thats what causes a ton of travel before you feel brake power. That and old fluid
40acres
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40acres 6/15/2018 7:56am
6/15/2018 7:56am Edited Date/Time 6/15/2018 7:57am
So, you have new pads that have an hour on them and you flushed out the line?

I would try flushing the fluid again as it sounds like there still might be some air trapped in there. It's not going to be the line unless there's a crack in it, but highly doubtful. You'd have to have some serious hours on that 2014 to even consider the line wearing out enough to pull your lever to the bar. You also might want to think about servicing the caliper. New set of seals on those pistons just might be the fix. If they were filthy when you pressed the pistons in for the new pads you might have gotten some debris in there or possibly air.

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