Brake lever flop

[ChipToothy]

Originally Posted by China Rider 27

Good to hear, you got it narrowed down, that is half the battle. Sounds like one of two things going on either the physical or hydraulic. If it is mechanical then you should be able to remove the line and see no improvement. If hydraulic when you remove the line it should release.

I think it’s corroded inside the caliper not letting the inside pad move enough. I may just soak the whole caliper in oil.

[China Rider 27]

Don't know how much soaking will help. I haven't looked at these brakes but disc brakes use a piston caliper that slides back and forth under hydraulic pressure which is considerable. On cars you can take the piston apart hone the cylinder smooth and replace it with new seals. If movement is that severely restricted it must mean a very scored or corroded piston bore which is likely not salvageable. I would see if I could get the pistons out to look at the issue.

[Rocket tests]

After reading thru this thread I need to ask: Are you absolutely certain the master cylinder is stroking all the way out when the petal is depressed? As many can attest to, linkage bound master cylinders will not allow new fluid to replace the fluid consumed by the displacement of a stroking brake cylinder.

[ChipToothy]

I’ve broke the caliper down 100% and have cleaned it and regreased the slides. I’m convinced the master cylinder isn’t pushing the fluid hard enough against the main caliper piston. I can get it to slowly walk the pads closed by repeated lever pushes, it won’t retract on its own still but slides open super easy if done by hand.

My final guess is the main seal/stopper inside the master cylinder or caliper has a small air leak. Looks like I’ll be buying the rear caliper and cylinder replacements for the TT250 on the CSC Motorcycles site. Can’t believe just changing a stupid flat has caused a complete brake failure.

Thanks for help everyone!

[ChipToothy]

Ok, I noticed yesterday part of the caliper along with 1 pad is now missing. So, will def be replacing the Master cylinder and caliper. The TT250 versions don’t look like they will bolt on to the Storm. Any ideas on what to buy?

[ChipToothy]

Got the new master cylinder in the mail. It still won’t move the main caliper piston enough to matter. I even pulled the main piston and filled the caliper with fluid, pumped out a couple air bubbles then pushed the piston back in. All I’m getting is a slight wiggle.

[Rocket tests]

I've had brake lines pinched shut before. They act just as you describe, fluid in nothing back out. It acts as a one way valve, mine was corrosion swelling a line clamp on my truck, opened the clamp a bit and all worked as it should.

[ChipToothy]

Originally Posted by Rocket tests

I've had brake lines pinched shut before. They act just as you describe, fluid in nothing back out. It acts as a one way valve, mine was corrosion swelling a line clamp on my truck, opened the clamp a bit and all worked as it should.

I’ve cleaned the line, ran water through it, submerged it and blew threw one end to see if there was an air leak. I’ve bled the line both directions probably 30 times or more now trying to see if it’s air. I’ve cleaned and greased the posts a few times. I’m just out of ideas. There’s just not enough force/pressure to move that main piston.

Whatever happened when I took the caliper off to change the flat I can’t figure out either and a caliper with the same 2 bolt on holes I can’t find to buy.

[China Rider 27]

Sounds to me like the brake master is still not putting out the force that is necessary? If the caliper piston moves back and forth easily by hand manipulation when removed from the bike it should easily under hydraulic pressure. To rule out the rear master, I would be tempted to remove the front brake caliper and connect it to the rear master and see if it would function normally. With the bleeder open, a press on the brake pedal should push out fluid. Could the brake pedal linkage still be in the running as an issue?

[ChipToothy]

Originally Posted by China Rider 27

Sounds to me like the brake master is still not putting out the force that is necessary? If the caliper piston moves back and forth easily by hand manipulation when removed from the bike it should easily under hydraulic pressure. To rule out the rear master, I would be tempted to remove the front brake caliper and connect it to the rear master and see if it would function normally. With the bleeder open, a press on the brake pedal should push out fluid. Could the brake pedal linkage still be in the running as an issue?

I replaced the master cylinder and have watched about 20 YouTube videos trying to find a way to pressurize the system. I have a big syringe with a line and have done reverse bleeds as well.

[China Rider 27]

Have you tried compressing the caliper piston with a c clamp to seat it completely?

[ChipToothy]

Originally Posted by China Rider 27

Have you tried compressing the caliper piston with a c clamp to seat it completely?

No, it doesn’t offer much resistance. I can just push it in closed by thumb or with the pad when the caliper is off and on the bike.

The avg eBay caliper is only about $26. I just can’t find one that will bolt on to the Bashan. If I take it to a shop there’s no telling what they will charge. The bike being 2 years old next month means my caliper and piston look 100 times better than most of what everyone is rebuilding on YouTube. There’s are mostly all rusted over and need rehabilitation. My piston still looks polished.

[China Rider 27]

That is a tough spot. Something is blocking the pressure from getting to that piston. I might look at ali express or taobao, of course a long wait but they may have something that might work.

[ChipToothy]

Going to press my luck with this one. I already have a new MC to pump but the caliper bracket here may have enough shape and meat to it that I can get away with drilling a bolt hole or 2 to match the bike.

[duck9191]

check with peace, the brozz caliber should fit. i have a brozz front rotor and speed sensor on my storm.