Brake Fluid

[Zathos]

In my search for a solution the Italian bad rear brake design I got into a debate on dot4 Vs dot5.1.

For the Tuono, people are recommending the dot5.1 as mitigation against the high temp problems.

Personally I'm a bit sceptical, however when investigating I noticed that dot5.1 is recommended for brake systems fitted with abs.

Something I never thought about but worth mentioning. Make sure you check the bike user manual before just going with the assumed dot4.

I'm gonna try the dot5.1 just to see if it helps.

[Zax]

The back break just needs to be blead properly . which is a bit time consuming and a pain.

however once you know how to do it properly it is fine for months and months regardless of the temperature / mileage done.

I have only used D4 with my Mille and had no real problems once I worked out how to get the air out the system. The other thing is that the 5.1 is more hydrosorbic? than the D4 so it may have to be changed more regularly any way.

[dyz]

Do share!

Found this on AF1 but haven't tried it myself: http://www.apriliaforum.com/forums/show ... ost1455889

[Zax]

Do share!

Found this on AF1 but haven't tried it myself: http://www.apriliaforum.com/forums/show ... ost1455889

The way the I do it is similar. with the caliper on then off the bike rotating it to ensure that there is no possibility of trapping any air.
All the rear brake problems come from incorrect bleeding and the air expanding once it warms up.
Takes about 15 mins to do once you have done it a couple of times.

[Zathos]

Bled the rear brake using the calliper juggle method and the brake did improve from being 'totally useless' to 'quite bad'.

Gonna bled it again this weekend to see if it was residual air or glazed pads.

The dot5.1 is more hydroscopic, but the interesting thing for general peeps (i.e. those without bad Italian designed rear brakes) is the recommended use on ABS systems.

The rear brake on the Tuono / millie is very poorly designed. Horizontal master cylinder, bleed nipple on the underside of the calliper, brake hoses run in a nice osccilating pattern....

...all makes for a right pain and no easy fix

[Zax]

another fix is to add the a heat shield to the master cylinder and put some exhaust wrap round the link pipe which runs behind the master cylinder . This will reduce the heat soak and ultimatly the expansion of any remaining trapped bubbles.

[meepmeep]

another fix is to add the a heat shield to the master cylinder and put some exhaust wrap round the link pipe which runs behind teh master cylinder . This will reduce the heat soak and ultimatly the expansion of any remaining trapped bubbles.

Have you got a stiffy?

[Zax]

another fix is to add the a heat shield to the master cylinder and put some exhaust wrap round the link pipe which runs behind teh master cylinder . This will reduce the heat soak and ultimatly the expansion of any remaining trapped bubbles.

..... something that added nothing to the thread......

[kennybhoy]

another fix is to add the a heat shield to the master cylinder and put some exhaust wrap round the link pipe which runs behind teh master cylinder . This will reduce the heat soak and ultimatly the expansion of any remaining trapped bubbles.

..... something that added nothing to the thread......

[meepmeep]

Added 2 posts

Don't fight it

[Coddy]

Remove the catwalliper, tie wrap it as high up (vertically) you can get it. Pump fluid through the system (always pump more than you think).
Fit a piece of clear hose the the bleed nipple on the catwalliper, so the brake fluid coming out runs down the pipe and not onto the bike.
Apply pressure to brake lever, crack open the bleed nipple, close the bleed nipple before the lever travels its full stroke. Repeat 1/2 dozen times.

[Zathos]

another fix is to add the a heat shield to the master cylinder and put some exhaust wrap round the link pipe which runs behind the master cylinder . This will reduce the heat soak and ultimatly the expansion of any remaining trapped bubbles.

Heat shield was fitted as standard from 07 I think.

Good idea on the link pipe

There is also a school of thought on increasing the bore at selected points to 4.5mm to aid liquid flow.
And replacing the rear disk with a slightly softer option.

I will get is sorted

[al]

another fix is to add the a heat shield to the master cylinder and put some exhaust wrap round the link pipe which runs behind the master cylinder . This will reduce the heat soak and ultimatly the expansion of any remaining trapped bubbles.

Heat shield was fitted as standard from 07 I think.

Good idea on the link pipe

There is also a school of thought on increasing the bore at selected points to 4.5mm to aid liquid flow.
And replacing the rear disk with a slightly softer option.

I will get is sorted

The Falco had the same setup and was fine! It was the clutch that I had issues with.

[dyz]

The Falco had the same setup and was fine! It was the clutch that I had issues with.

Not quite Big Kneed Al (master of the emergency stop & "stand up" comedian),

Here's the Tuono setup:



Falco's MC is mounted on the rear set:



What was wrong with your clutch?

[al]

The Falco had the same setup and was fine! It was the clutch that I had issues with.

Not quite Big Kneed Al (master of the emergency stop & "stand up" comedian)(master of the emergency stop),

Here's the Tuono setup:



Falco's MC is mounted on the rear set:



What was wrong with your clutch?

Went out to the bike one day after it had been sat for a while and the clutch lever came back to the bar with no resistance. It was cured by careful bleeding.

Big Kneed Al (master of the emergency stop & "stand up" comedian).

[Coddy]

There is also a school of thought on increasing the bore at selected points to 4.5mm to aid liquid flow.

When i had my Mille Factory, i remember there was a kit to increase the size of the bore for the master cylinder, but can't remember the sizes.

[coullstar]

Just dont use it, works for me

[The Rossi Kid]

Just dont use it, works for me

I thought that but then he does get a lot of pleasure from making certain under tale female members of the club fly through the air by jumping on it at the last second before a really big drop in the road!