Spongy front disk brake

[Benman]

So I had the front wheel off to change the tyre and now it's all back together my front disk brake on my mtx125 has gone all spongy and lost its sharpness. What's happened and what can I do to fix it???
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Ben1972

[Matt-]

Brake's need bleeding - their is air in the braking system, simple solution is gravity bleed - crack the bleed nipple on your front caliper, while putting tissue under the nipple so brake fluid does not go everywhere.
while fluid is coming out keep topping up the brake res on your handle bars, also check you have got the brake hose on correct and not kinked, once you see fluid coming out you should see air bubbles coming out, keep topping it up until you see just fluid coming out.

If this doesn't work you will have to manually bleed it up

Good Luck.

Matt
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RIP jack (wheelie king), you will never be forgotten.
Current Bike's - Road Legal TZR 125 Pitbike, Aprilia SR50R 2010

[Benman]

Ok I get that but I haven't done anything to introduce any air into the system. I only took the wheel off!!!
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Ben1972

[Matt-]

If you ave moved the caliper / caliper pistons air may have entered the system or you may have a knackered seal on the caliper.

Other thing i would also try is cleaning your disc down with water, reason being if anything other than water hit's it, brakes become useless

Good Luck

Matt
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RIP jack (wheelie king), you will never be forgotten.
Current Bike's - Road Legal TZR 125 Pitbike, Aprilia SR50R 2010

[Benman]

Cheers dude will the the bleed ago this eve. Will try the gravity feed first. Less hassle. Will let ya know how I get on.
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Ben1972

[Kickstart]

Hi

If this has happened after taking the wheel of the bike then I would suspect more likely it is the caliper sticking on the pins it slides on (disturbed by removing the wheel).

Check the caliper slides easily on the pins.

Might be worth bleeding the brakes as well, which is easy enough.

All the best

Keith
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