Bleeding the brakes on a 2000 ST1100AY.

[Bobcp]

Please can anyone advise whether or not you can vacuum bleed the brakes on a 2000 ST1100AY using a Mityvac or similar ?
I have already contacted Mityvac technical advice centre but they simply refer you the the machine manufacturer.
Thanks in advance for any advice which is appreciated.

Bob (Parsons)

 

[Oldbikefixr]

Yes.

 

[jfheath]

And No.

I find vacuum bleeders brilliant for maintaining a constant steady flow of fluid while I go round and encourage the bubbles to let go of the sides of tubes, to move round n bends an u bends, and to stop hiding in the corners of joints.

But for bleeding the last visit to each bleed valve, no. The air sucked past the bleed valve threads means you cannot tell whether the lines are free of air by looking at the bubbles coming out. There are always bubbles. So use it to do the heavy work, use a bleed valve for the final finesse.

If you are checking whether it is physically possible - yes. The only complex bit is the fluid from the brake pedal, through the SMC to the rear outer pistons - and even that is straight forward - as the fluid just pushes past the primary seal of the SMC. Although the SMC is in a better vertical position on the ST1100AY than it is on the 1300, it is always a good idea to exercise its full movement with the rearmost bleed valve of the rear caliper open.

Check the movement and the bearings in that 3-hole linkage casting too.

For anyone looking in, the layout of the calipers and hydraulic lines on the St1100Ay are pretty much the same as on the 1300.

 

[CYYJ]

But for bleeding the last visit to each bleed valve, no. The air sucked past the bleed valve threads means you cannot tell whether the lines are free of air by looking at the bubbles coming out. There are always bubbles. So use it to do the heavy work, use a bleed valve for the final finesse.

Exactly. Excellent advice.

Michael

 

[SMSW]

I used a vacuum pump every time I bled my 1300, and have used it on my Guzzi's and my VStrom. Yes, as John said it tends to suck air in to the hose around the threads of the bleed nipple. However, if your brakes were firm to begin with, there was little to no air inside the system and those tiny bubbles get sucked down the hose into the reservoir before they can go into the caliper. I've never had a problem using either my MityVac or my vacuum pump, and vacuum bleeding was the ONLY way I was able to completely purge my Guzzi's new braided brake hoses of all the air.

I put Speedbleeders on my VStrom and they come with thick thread sealant on the threads to prevent air entry. These work great and remove the need for a vacuum bleeder, but don't match the speed of one. They are probably too expensive for the ST because of all the bleed nipples.