[Ducati] 748 brakes (fluid level)

[Jim Calandro]

Hey Y'all

If this is old news to you please pardon me and move on to another topic.

I just thought that seeing how dangerous a lock up of the brakes can be I 
might review several things that can cause this.

1. Air in the line will expand much more than fluid will so improperly bleed 
brakes can heat up, especially at the track, can cause the air to expand and 
cause the brake pads to drag.  This will generate a lot more heat and make 
it even worse.

2. Corrosion in the system that will cause the pistons to not fully retract 
will also cause the pads to drag and heat up the system.  The fluid will 
expand but not like air, see above.

3. Misadjusted levers.  I have seen a rider at a track day who installed a 
new set of rear sets but did not get the proper free play between the pin on 
the back of the brake lever and the piston in the master cylinder.  This 
caused the pads to drag and he generated enough heat to melt the aluminum 
pistons in the rear caliper!  Some one lent him a second caliper and he 
melted the second one!

4. Blocked return orifice in the master cylinder.  I had a bike I bought 
used that the front brakes were a major problem.  I bought a rebuild kit and 
when I pulled off the reservoir I found that the PO has added a little 
something extra.  It was a piece of the aluminum seal that is on top of a 
new bottle of brake fluid.  A small piece had fallen into the reservoir and 
was acting like a flapper valve and not allowing the piston to bring in new 
fluid as the brake pads wore.  It made the brakes very wooden with no power.

Moral of the story from all of the above is be careful.

Jim

Jim Calandro
il Capo
US DESMO
www.usdesmo.com
704-843-0429