Front brake master cylinder

discussions specific to the 907IE
Post Reply
nickta
Posts: 295
Joined: Tue Jul 24, 2012 8:54 am
model: 907 I.E.
year: 1992
Location: Cairns, Queensland, Australia

Front brake master cylinder

Post by nickta »

Hi everyone.

I have just replaced the old rubber brake lines with HEL stainless lines, and found a little problem in the process. Without the lines connected to the calipers, brake fluid runs out constantly without the brake lever pulled in. Makes it easy to bleed the air out, but doesn't seem right to me? I'm thinking the brake master cylinder needs a kit put through it. Does anyone know the Brembo part number of the kit? Or failing that, the Ducati part number?

I'm also thinking a radial brake master might be a reasonable upgrade, with a remote reservoir. Has anyone taken the plunge and fitted one?

Cheers.
Nick.
Mc tool
paso grand pooh-bah
Posts: 1873
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Newzealand

Re: Front brake master cylinder

Post by Mc tool »

The fluid should run straight thru as you describe Nick . With the piston assy at the normal resting position the port from the resiviour to the cylinder should be open and the fluid will flow , if you pull the lever in a bit ( thus closing that port ) the flow should stop. Im pretty sure I have the correct Brembo kit somewhere so I will look it out and get the part # off it for you . Those kits are also available from MG's , just need to know the diameter. Some of the whole master cylinder assys are cheap enough to just put a whole new one on there :)
Hamish
I wish I was young again............Id be heaps smarter than last time
nickta
Posts: 295
Joined: Tue Jul 24, 2012 8:54 am
model: 907 I.E.
year: 1992
Location: Cairns, Queensland, Australia

Re: Front brake master cylinder

Post by nickta »

Hi Hamish.

It seemed a bit odd the fluid ran through. I did look at a few master cylinders on eBay. The you beaut, straight from China are beer money, but quality could be an issue? I have a British Princess sitting next to the 907 and it has a radial brake master (hence the second question). I thought the 907 had reasonable brakes, but you don't realise how much brakes have evolved until you take the Ducati for a run, and then jump on the other. Savage is a word that come to mind.

The 907's brakes are better with the HEL brakes lines, but still a little to go. It has been having a rest for about 12 months, so all the little rubber bits have dried out. The first time I went out on it after replacing the lines, one of the fork seals started leaking big time. Everything on the LHS is drenched in oil. So that is next, new brake pads and see what happens.

Cheers.

Nick.
angelix
Posts: 338
Joined: Thu Nov 29, 2007 2:38 am
model: 907 I.E.
year: 1990
Location: UK

Re: Front brake master cylinder

Post by angelix »

On mine, I had a couple of scares i.e. lever touching the handlebar trying to stop at a traffic light; at the time I though the issue was with the fluid so I replaced it and after bleeding it several times I decided the MCs where crap and replaced them with the Serie Oro from a 916.

Some purists will say "I ruined the bike's Originality", but I believe it is a mod that could have been made at the time of the bike production, therefore... yes, it is not original, but is not out of place.

With the serie oro the bike brakes as it should, looks nice and feels very nice.

Of course I also replaced the calipers, Serie oro all the way.
Attachments
P1030730r.jpg
P1030730r.jpg (80.95 KiB) Viewed 9142 times
P1030729r.jpg
P1030729r.jpg (91.62 KiB) Viewed 9142 times
Mc tool
paso grand pooh-bah
Posts: 1873
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Newzealand

Re: Front brake master cylinder

Post by Mc tool »

They look to be the same as the ones on my old SS. I don't think that originality is lost if the mods can be reversed , its not like you had to cut off the old caliper mounts and weld new one on
I wish I was young again............Id be heaps smarter than last time
nickta
Posts: 295
Joined: Tue Jul 24, 2012 8:54 am
model: 907 I.E.
year: 1992
Location: Cairns, Queensland, Australia

Re: Front brake master cylinder

Post by nickta »

angelix wrote:On mine, I had a couple of scares i.e. lever touching the handlebar trying to stop at a traffic light; at the time I though the issue was with the fluid so I replaced it and after bleeding it several times I decided the MCs where crap and replaced them with the Serie Oro from a 916.

Some purists will say "I ruined the bike's Originality", but I believe it is a mod that could have been made at the time of the bike production, therefore... yes, it is not original, but is not out of place.

With the serie oro the bike brakes as it should, looks nice and feels very nice.

Of course I also replaced the calipers, Serie oro all the way.
Yep, this is exactly what I would like to fit to the 907.

Some would say you may have ruined the bikes originality, but when you are planted in the front of someone's bonnet 'cause you couldn't stop doesn't do a whole lot for originality either!

The hunt for a set of M/C's is now on.

Cheers.

Nick.
Tamburinifan
paso grand pooh-bah
Posts: 1527
Joined: Thu Jun 21, 2007 12:00 am
model: 907 I.E.
year: 1991
Location: Gothenburg, SWEDEN

Re: Front brake master cylinder

Post by Tamburinifan »

Replaced my clutch w a M695 one.
Bit fiddly w fitting idle lever, otherwise bolt-on.
And original look.
Simpler model ones fr this millenia possible fit.
Gert

907 I.E. -91
M900 -97
MTS 1100s -07
Mc tool
paso grand pooh-bah
Posts: 1873
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Newzealand

Re: Front brake master cylinder

Post by Mc tool »

New or 2nd hand Nick ? Im pretty sure I still have the clutch side .... and there was no issue fitting it over the choke ( Im assuming that's what Gert means by idle lever ) as the SS had the same handle switch assy as the Paso . Apart from looking a bit more "tech " ( gold , remote rez and adjustable has got to be hard to beat :D ) than the standard ones I couldn't see them making any real difference ..... as long as the overall pump/lever ratios were the same :)
I wish I was young again............Id be heaps smarter than last time
Tamburinifan
paso grand pooh-bah
Posts: 1527
Joined: Thu Jun 21, 2007 12:00 am
model: 907 I.E.
year: 1991
Location: Gothenburg, SWEDEN

Re: Front brake master cylinder

Post by Tamburinifan »

On a 907, it`s an idle lever, it just lifts the butterfly abit.
It does not restrict air to TB`s.
Gert

907 I.E. -91
M900 -97
MTS 1100s -07
Mc tool
paso grand pooh-bah
Posts: 1873
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Newzealand

Re: Front brake master cylinder

Post by Mc tool »

Tamburinifan wrote:On a 907, it`s an idle lever, it just lifts the butterfly abit.
It does not restrict air to TB`s.
Yeah your right :) , I keep forgetting that the 907 is injected :banghead:
I wish I was young again............Id be heaps smarter than last time
nickta
Posts: 295
Joined: Tue Jul 24, 2012 8:54 am
model: 907 I.E.
year: 1992
Location: Cairns, Queensland, Australia

Re: Front brake master cylinder

Post by nickta »

Hi Hamish.

I found a set of M/C's off a 996. Worth a few Bob, but you get that. After 12 months in storage, they are going back in again for another 3, so all the good ideas will have to wait again.

Cheers.
Nick.
Mc tool
paso grand pooh-bah
Posts: 1873
Joined: Wed Dec 05, 2007 12:35 am
model: 906 Paso
year: 1990
Location: Newzealand

Re: Front brake master cylinder

Post by Mc tool »

I stripped mine and got all the brake fluid out and re assembled with brake assy lube . Just reasoning that moisture would get into any residual fluid and cause corrosion
I wish I was young again............Id be heaps smarter than last time
Post Reply