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I just purchased a new 2005 silver ST3 and finally got a short (80+ mile) trip in yesterday.

Everything went as expected. I definitely need to get the risers to take some pressure off my (formerly broken) left wrist.

BUT my main surprise/concern was that the rear brake had virtually no stopping power. (The front brakes by contrast were excellent.) I was mashing on the pedal about as hard as I dared and nothing was happening.

What's the deal? Is it simply breakin time needed?

Your input and insight will be much appreciated. Thanks.
 

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That is normal for these bikes. Some have made some minor mods to get the rear to brake more effectively, others, myself included, pretty much rely on just the fronts. Under hard braking there's very little weight on the rear anyway. It would be interesting to hear from Ducati exactly why they set it up this way.
 

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kentamcolin said:
That is normal for these bikes. Some have made some minor mods to get the rear to brake more effectively, others, myself included, pretty much rely on just the fronts. Under hard braking there's very little weight on the rear anyway. It would be interesting to hear from Ducati exactly why they set it up this way.
The old "rear brake thread" returns with every new member. Here is my theory: the experts say 70-80% of your braking should be via the front brake. By use of a stiffer rear brake, Ducati has engineered this braking percentage into the bike. Think of the front brake as the one which stops the bike and the rear brake as the one which keeps the bike upright and prevents the rear wheel from sliding out during hard (emergency) braking.

To illustrate my point, attached is a photo of my late 02-ST4s after a woman decided to do a U-turn in front of the mechanic who was taking it for a test ride. Note the skid mark is straight. The rear wheel did not slide out during the emergency brake application and the bike remained upright until it hit the car.
 

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Chilehead
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The more you use it, the better it works. Also works better with a passenger, locks up too easily without.

Tom
 

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With all do respect, I disagree with everyone who says the rear brakes on the Ducatis (ST series or Superbikes) is usless. On my 748 and old ST4 I can/could lock the rear brake at will. On my ST4S-ABS I can activate the ABS.

The reason the rear brake does not work well on your bike is caused by two things. The most important being there is air in the hydraulic system and second lack of use will cause the surface of the pads and rotors to get imbeded with brake dust and other road grimes (glazed) reducing its effectiveness. Some pad material also work better than others.

Properly cleaning both surfaces and bleeding the rear brake will restore the brakes.

Also note that if your hydraulic fluid is older than one year, more than likely it has moisture in the fluid. A 2% moisture will reduce the boiling point of a DOT-4 brake fluid by close to 100 degrees F. This means that the moisture in the fluid can boil and turn into gas (air) a lot sooner as the fluid starts getting hot. The air will cause the brake to fade. It is not a bad idea to flush your brake fluids (front and rear) every six months. The following two articles have some very good information about what happens to brake fluid as it gets old. I recommend you read these articles. They might provide some additional insight that might be helpful in your case:

http://www.aa1car.com/library/bfluid.htm

http://www.babcox.com/editorial/bf/bf40142.htm

If you decide to flush your brake fluid, I suggest you remove as much fluid as you can from the reservoir by bleeding the old fluid out before adding the new fluid to it. This will insure that you get most of the old fluid out.

-Fariborz
 

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Fly>

I found the same with my 06 ST3. I have done about 1,500km now and it's starting to get better. The more I use it, the better it gets.

I had a tendancy to only use fronts, so the rear wasn't getting any better. I am making sure that I use the rears now.

CB
 

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Mine was useless at first, too... when it was new. Like the pads were greased.

I don't use much rear brake except with passenger. I think it started working after about 500 - 700 miles. About 4000 miles now, and it works like any other bike, maybe not quite as strong, which (as some have pointed out here) is not always a bad thing.


(now if the false neutral between 5th and 6th would just stop happening - no matter how firmly I shift it, about every 3 times)


:)
 

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LiquidSilver said:
Snip
(now if the false neutral between 5th and 6th would just stop happening - no matter how firmly I shift it, about every 3 times)
Not to get off topic but, if you preload the shifter with your toe in anticipation of the shift, you’ll have fewer false neutrals and much slicker shifting. Not sure why but I believe it takes the play out of the shift linkage, and makes for more positive shifts.
 

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Fly said:
BUT my main surprise/concern was that the rear brake had virtually no stopping power.
Try bleeding the rear brake. A friend had a brand new ST3 who's rear brake was useless also. We bled the brake and it worked fine after that. Now, the rear brake on my '04 ST4s has always worked fine. Italian attention to detail, I guess... ;)
 
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