Ducati Monster Forum

Moto Board => Tech => Topic started by: Craw on February 04, 2009, 09:12:38 AM

Title: Rear Brake Suddenly Not Working. What should I look for?
Post by: Craw on February 04, 2009, 09:12:38 AM
Hello,

I noticed this morning that my rear brake isn't working at all. The lever feels like it moves freely and the brakes don't engage. I have an 06 Monster Dark. When fully depressed, i can still move my bike back and forth with no problem. The brake was working properly the last time I took the bike out which was about a week ago. Bike hasn't been dropped or crashed.

Could it be a bleeding issue? What are some things I should check out first to figure out what the problem is?

I'm fairly mechanically inclined, however my only experience with hydraulic disc brakes are with my mountain bike.

Thanks for your help!

Title: Re: Rear Brake Suddenly Not Working. What should I look for?
Post by: wbeck257 on February 04, 2009, 09:20:56 AM
Sounds like you got an air in the lines.

Bleed them. See if that helps.
If it happens again, your master cyl. is going out.
Title: Re: Rear Brake Suddenly Not Working. What should I look for?
Post by: Howie on February 04, 2009, 10:13:06 AM
Or caliper.
Title: Re: Rear Brake Suddenly Not Working. What should I look for?
Post by: ghosthound on February 04, 2009, 10:44:26 AM
my rear pad wore out at around 5800 miles...
Title: Re: Rear Brake Suddenly Not Working. What should I look for?
Post by: wbeck257 on February 04, 2009, 11:29:01 AM
If it were pads it wouldn't be sudden...
Title: Re: Rear Brake Suddenly Not Working. What should I look for?
Post by: Slide Panda on February 04, 2009, 11:35:12 AM
When in doubt, bleed it.  It's the cheapest and easiest thing to check.  Can't hurt to check the pads while you're mucking about back there.  But a good bleeding will probably sort it.
Title: Re: Rear Brake Suddenly Not Working. What should I look for?
Post by: fasterblkduc on February 04, 2009, 11:37:00 AM
Your bike sat for a week? Just pump the lever until you have brake pressure. Then try it.

Title: Re: Rear Brake Suddenly Not Working. What should I look for?
Post by: DuciD03 on February 04, 2009, 04:15:16 PM
dark 06 - how is the rear caliper mounted?

If its the one mounter below the swingarm; they are difficult to bleed mounted with an air pocket in the caliper; its better to unmount  the caliper and have the bleed screw at the high point; then bleed.  I the first time i discovered this was with a crashed bike and I spent a lot of time & break fluid getting no where ....

Also it is unusual for a problem like that to just show up. What work have you done to the bike?  Check the break lines and calipers any leaks? and any loss of fluid?

I'll bet ya there in lies the problem-o.  Happy bleeding.
Title: Re: Rear Brake Suddenly Not Working. What should I look for?
Post by: Craw on February 05, 2009, 02:48:04 PM
Quote from: DuciD03 on February 04, 2009, 04:15:16 PM
dark 06 - how is the rear caliper mounted?

If its the one mounter below the swingarm; they are difficult to bleed mounted with an air pocket in the caliper; its better to unmount  the caliper and have the bleed screw at the high point; then bleed.  I the first time i discovered this was with a crashed bike and I spent a lot of time & break fluid getting no where ....

Also it is unusual for a problem like that to just show up. What work have you done to the bike?  Check the break lines and calipers any leaks? and any loss of fluid?

I'll bet ya there in lies the problem-o.  Happy bleeding.

Brake Caliper is mounted above the swingarm I'll take a look at everything this weekend hopefully.

Thanks!
Title: Re: Rear Brake Suddenly Not Working. What should I look for?
Post by: Gimpy on February 05, 2009, 04:33:45 PM
This happened to me on a ride.  It was a hot day, and I was on an old twisty road with lots of gravel. So I was cranking on the rear.  It turns out that I blew my master cylinder.  I looked into rebuilding it buts its cheaper to just replace. 

Try bleeding them before you do anything.  Good luck. 
Title: Re: Rear Brake Suddenly Not Working. What should I look for?
Post by: somegirl on February 05, 2009, 06:38:05 PM
I had a similar issue last year and my rear brake just needed bleeding.