Ducati 996 front brake locked up?
 

front brake locked up, threw me off 9mnth old 996s. dealer now(accident occured 02/02/2003), claims inferior fluid caused this, not paying up!!. i had the bike 4 days, first ride, clear sunny day. Bike had 12 month service prior to delivery(900 miles on clock). master cylinder, was first id'd as problem by dealer(verbally) and changed. Accident damaged parts replaced by dealer - as good will gesture. will not pay up for helmet leathers injuries etc.. help any one?- Solicitor seems to be given up. (n.b. mastr cycl sent to brembo - no fault found, blamed wrong brake fluid). dealer claims can not verify who put fluid in - as if i would change after 4 days!!. Once again advice would be great

Hello, I'm not expert but if you have some proof that the dealer has sold you the bike with the wrong brake fluid and that it caused the accident, you've probably got a good case to sue them.

I'd contact RiderSupport.co.uk talk with them and see what they say. Costs nothing and they can be really heavy when required.

If they say not to pursue it then I wouldn't

Name the dealer...its probably not the first time!

Errrrmm,

I'm no expert on this, but didn't I read somewhere that people often 'adjust' the brakes using the screw that sits in the brake lever and pushes on the master cylinder actuator. I'm sure I read somewhere too that if you screw it in too far, you might think you're adjusting it for a nice firm lever feel, but you can also stop the fluid returning to the master cylinder. Wouldn't this jam the brake on after a little squeeze?

Easy to hide again as well, I'd have thought? Just tweak it back again and say 'not me guv'.

erm...neither I am any expert on this, but can't think of why a different brake fluid would cause it to lock up....there can't be that much difference in different manufacturers fluids for a standard road bike can there? More likely to be pads? Or suspension set up? Or road conditions - wet, gravel etc?

WeeJohnyB

Yes Jools that has been known to happen

It depends if the brake fluid has been mixed with the previouse, ie dot 5 mixed with lower spec dot 4 or below, it happened to my mates race bike after dot five was added. Or if you mix synthetic with mineral, it is how they react with each other & what they then do to the seals in the calipers, master cylinder.

I am sure Neil or Shazam will come up with a more technical explanation shortly.

Chris. :roll:

Ducat brake lock up
 

Unable to prove what brake fluid M&S motorcycles and scooters (Wesgate road Newcasle upon tyne) put in, as after the crash the master cylinder was changed and i presume the brake fluid replaced. To be honest i dont think it was the brake fluid, but im not sure whether manufacturer is going to admit a fault with the cylinder.
Conditions on the day were dry, no oil on road, slow left hand 2nd gear corner.
Does this kind of excuse mean, that when you purchase a bike with a warrenty it counts for nothing, if a dealer could turn around and say"you must have changed the brake fluid or you have put dodgy oil in the engine". Surely any one with an ounce of commom... could see that on this occasion no one other than M&S have touched the bloomin thing - i only had it for 4 days?

Thanks for the replies, i will contact those groups that you mentioned and i am considering contacting MCN's and my local rag. Cheers again. from one disapointed, disillusioned motorcyclist, getting screwed on the road and screwed off it.

Sounds like more than a fluid problem IMO.
You can mix "conventional" fluids, such as DOT 3, 4 or 5.1.
The .1 is the crucial part where the 5 is concerned though.
A DOT 5 is a silicone based race fluid whereas the 5.1 is a high performance road fluid.
The silicone based 5 doesn't mix with normal fluids and can cause the seals to swell. This stuff is expensive though, and you wouldn't see it in a normal service workshop??
The small screw that controls the piston travel isn't there on the brake lever, only the clutch.
The one thing I can think of that could cause it would be a pattern lever. There are several types and some are crap.
I fitted one to an Aprillia RS250 and it wasn't quite right and didn't allow the piston to return fully. Essentially it dragged the brakes and as the heat built up, it locked solid. Fortunatley, it happened pretty quickly, I was riding it and the RS isn't exactly endowed with buckets of torque to pull off quickly.

Good thinking Nelly. I also heard of other people buying supposedly genuine levers for Dukes and Aprillias from ebay and they were pattern parts.

Do a search on here for 'levers' and see what comes up. I'm sure it was discussed here before. If the bike was secondhand, contact the previous owner from the reg doc.

MCN would be a good route - the dealer will not want that at all !!

I have seen a pattern lever cause a front brake to lock as well, on an R1 though.

Can't really see "wrong" fluid causing a problem severe enough to lock a wheel.

I would say you have done pretty well to get the dealer to repair the bike.

If you don't have all the parts that were on the bike at the time of the crash you are going to have trouble proving anything.

Had a problem with a CBR6 with the rear brake caliper falling off immediately after a service, the dealer apologised, supplied a new bolt taken off a bike in the showroom to replace the one that fell off but when I mentioned the paint that had been chipped off the rear wheel as the caliper flapped about they just gave me a tin of paint to sort it out myself!

Ray

ducati brake locked up
 

Original brake lever is still on the bike, or would this be changed when they replaced front master cylinder. How do i contact the webteam?
M&S(dealer) were not going to pay originally for the damage to the bike(£1500.00), because the test rider could not recreate the locking problem. The day before i was due to pick up the bike, and pay the dosh, they phoned me and told me that their test rider had now in fact experianced the front end locking up (he didnt come off though). It was then and only then that they believed my original explanation, paid for the damage and replaced my 996s front brake master cylinder with a new one from a 998?? admitting that the master cylinder was at fault and that they were sending the offending part to ducati uk. for examination. - and so it goes on.

Well that is a partial success, hope you get it fully sorted, I think a full written apoligy, bike paid for & leathers etc, plus expensis.

Chris.:roll:

Think i will stay clear of that bike shop!

Name and shame thats what they need.

It's about time these people realise without us they would not have a shop!

I would go to traiding standards defo they will help you to get a fair result.

All the best

Mark:mad:

[Edited on 6-2-2004 by Mark853]

Would that be M&S in Westgate Road??

First, let me say that there’s no such thing as inferior brake fluid. All brake fluids sold today meet one of the DOT specifications, so no matter which one you use, it’ll work fine. Even if you use fluid from a unsealed container, the worst thing that can happen is that the fluid absorbs moisture and will boil if it gets to 300ºF or so. The same thing happens if you don't change your brake fluid once a year or so. The absorbed moisture in the fluid will, however, eventually corrode expensive brake bits over time.

In fact you could put straight water in there and it would work, it would just boil at a lower temperature (212ºF.)

DOT 3 and DOT 4 fluids are compatible with DOT 5.1 - but are not compatible with silicone-based DOT 5. DOT 5 brake fluid is purposely dyed purple to warn against accidental mixing, so you should be able to tell right away if someone added any purple fluid. Another way you can tell is that the DOT 5 fluid will coagulate in the reservoir when it’s added to any of the others.

One concern is that DOT 5 does not absorb water, so any moisture in the hydraulic system will "puddle" in one place. This can cause localized corrosion in the hydraulics.

Also, Brembo products are said to use natural-rubber base seals that are incompatible with DOT 5 silicone-based brake fluids, and there were reports of DOT 5 causing premature failure of rubber brake parts with early DOT 5 formulations. This was found to be due to improper addition of swelling agents and reportedly has been fixed in current formulations.

However, nothing discussed above will lead to brake lock-up. The worst thing that can happen is that you start to have piston retraction problems so the pads drag continuously on the rotor. If the pads drag, the calipers and rotor can get pretty hot as you’d expect. But again, there’s no way that this will result in a lock-up condition.

So when they say they think that it’s a brake fluid or a master cylinder problem, they’re really saying that they just don’t know.

Two possibilities come to mind:

The first is that they failed to assemble the brake mechanicals properly during a recent service, they saw evidence of this, and decided to pay for the repairs (without admitting fault and incurring only limited liability.) I once had a situation where the owner of a Ducati dealership forgot to tighten down the four pinch bolt holding down my front axle, so believe me mistakes happen. If something was loose when it left the dealer, a mechanical interference problem in a left hander (not necessarily right away) is one way that the front wheel would abruptly stop turning.

The other possibility is just bad luck. A piece of metal in the road could get kicked-up and lodge between a rotating and stationary brake (or suspension) part. A small bolt caught in one of the rotor’s cooling holes, for example, will stop the wheel quickly enough to cause you to loose traction, shear off, and leave you wondering what happened.

Since you don’t know what really happened, my suggestion to you is this: Let it pass. There’ll come a time when you may need help from this dealer again. In my case, I went back to the owner (remember he was the one who made the mistake), took him aside and explained his mistake and (suggested) the wisdom in having the shop’s work double-checked when there were obvious safety-related and liability issues. The next time my bike was serviced, I was treated like royalty.

Hi Steveg,

Had the same problem with a badly adjusted lever a long while back. If they replaced cylinder but not the lever the problem would get transfered. Would be very suprised to find any brake fluid to be the problem. Besides it's not your problem even if it was possible. If it was me I would definetly carry on pursuing this. You would see some pretty major damage if a lump of metal had jumped in your wheel, disk etc, big enough to cause a large braking action. Missing wheel spokes or exploded disks should give this away. Perhaps you could get an independent motorcycle dealer to pressurise the system in reverse and push fluid from the caliper back into the mastercyl resevoir. Check the flow rate. Now remove the lever and see if the flow increases. If it does then the lever is wrongly adjusted. Don't change it as this is your evidence. Good luck mate.

Alternatley give your lever to a "mate", go for a nice long ride, if he craches you know what the problem was.......:roll: