No Front Brake

odw650 · Full Member Joined: Aug 05, 2005 Posts: 28

I went up to the bike today, (it's been sitting all winter) and I noticed the front brake is loose and the brake doesnt work.

How would I go about troubleshooting this? I'm a little worried about messing around with the braking system.

grizld1 · Posted: March 8, 2006, 12:11 am Post subject: Re: No Front Brake

By "loose," do you mean you have no pressure on the lever? That's not unusual when the bike's been sitting. First try following the bleeding procedure in your manual. Don't know what your service history is, but brake fluid should be changed every couple of years anyway. If it hasn't been, first restore pressure by bleeding the brakes (have fresh fluid on hand), then pull as much fluid out of the reservoir as you can with a basting syringe and refill. Then crack the bleeder valve, run a line from it to a bottle, pull back the brake lever, and tie it back. Close the bleeder valve, release the brake lever, top up the reservoir, open the valve, and go again, till the fluid coming out looks clean and fresh.

odw650 · Full Member Joined: Aug 05, 2005 Posts: 28

Ok thanks. The lever has no pressure. What do you use to acctually bleed the brakes? It's like a valve that redirects it too the resevoir or do you just dump the fluid out of the system? And why would it completely lose pressure just by sitting?

Never done it before but oh well might as well learn how on the bike, that's partially why I bought it. I'll take a look at the service manual, I'll see if I can get anything from that, but the pictures in there are really hard to see.

grizld1 · Posted: March 8, 2006, 10:53 am Post subject: Re: No Front Brake

When you bleed the brakes you pump out any air that may have been in the system. First remove the top of the reservoir and the diaphragm. Then pump the brake lever slowly, and look for air bubbles forming in the fluid in the reservoir. Keep going till the lever firms. That may take awhile! Don't worry if you stop seeing bubbles but the lever still hasn't firmed; keep pumping.When you have pressure, you may need to bleed air out of the caliper; but if you change out the fluid, that'll happen as you pump out the old stuff. When you replace the diaphragm, return it to its compressed state--popped-in, rather than popped-out.

odw650 · Full Member Joined: Aug 05, 2005 Posts: 28

Ahh I did something stupid. I took off the cover and diapraghm, filled it up a bit and started pumping and noticed that the bubbles moved really slow. Then I realize that I put in power steering fluid instead of brake fluid! I blot out the power steering fluid, fill it with brake fluid, take it out again and fill it with brake fluid but now it has these oily bubbles in it and the air is struggling to come through when I pump the lever.

Guess I should replace all the fluid? I noticed the rear brake is loose too.

grizld1 · Posted: March 12, 2006, 1:29 am Post subject: Re: No Front Brake

Yep--all the fluid, for sure! Flush it out as described as soon as you have pressure--open the bleeder valve, pull back the lever and tie it back, close the bleeder valve, release the lever, open the valve and pull again, topping up the reservoir at need. Keep going till all the contamination's flushed out.

If you have a disc brake in the rear, the drill's the same.

Your experience reminds me of a stunt I pulled a few years back. I was painting a sidecover, and was set to spray a 4th coat of laquer over 3 handrubbed coats. I'd done 2 or 3 passes when I realized I'd picked up a can of rust inhibitor....

What Happened to 650rider.com?

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