Ducati Sporting Club UK > DesmoDue Race Series > DesmoDue - General Questions and Chat > Brake master cylinder sizes - Jap stuff

[skidlids]

Phil my list is based on Master cylinders I have
I'm pretty sure they are in the right order

[bradders]

coolio, about what I thought, so must be learning something

and Multi size brake? 16mm I suspect...

[skidlids]

748/916 etc use a 16mm front brake m/cyl for operating the two 4-pot calipers they come fitted wirh as standard, I found fitting one of these to a single caliper didn't give me anywhere near the feel that I wanted

[bradders]

no different to what I have then, but if the magura is too much I may stick it on the multi if I keep it

guess i should look at a ZXR400 size instead just in case, although I found the 19x20 I had was fine and that wasn't that different with two calipers as a ratio than 16mm with one

[skidlids]

And again the point is missed, its not just the piston diameter but the combination of the piston diameter and the lever ratio that also plays apart.

Magura recommend the 195 radial m/cyl with a 16mm diameter for bikes with two 4-pot calipers
Brembo recommend their 16 X 18 and 16 X 16 m/cyls for bikes using one 4-pot caliper

[bradders]

Originally Posted by skidlids

And again the point is missed, its not just the piston diameter but the combination of the piston diameter and the lever ratio that also plays apart.

Magura recommend the 195 radial m/cyl with a 16mm diameter for bikes with two 4-pot calipers
Brembo recommend their 16 X 18 and 16 X 16 m/cyls for bikes using one 4-pot caliper

but Magura dont mention the lever ratio (that I've seen) and I assumed (maybe incorrectly) that most 16s will be the same ratio

I noticed on my 19x20 brembo that the closer to the bar the lever was set the softer and easier it was to pull and the magura seems to be the same. Is adjusteing the span adjuster making this affect? Also happens on Multi ones too...

[skidlids]

Adjusting the span is just that, making the span fit your hand, if its closer to the bar its easier for you to pull, but doesn't change the amount of fluid you move, that is the same amount of mm travelled by the lever moves the Piston by the same amount as before say you pulled the lever in by 20mm the piston will have moved 4mm no matter where the span is set.

Magura quote a lever ratio of 1 to 5 for the 195 range (the one you have)
and they quote 1 to 7.2 for their 190 range of Radial Mastercylinders.

Brembo figures refer to Piston Diameter and Pivot point position

Had a little look earlier and among my Jap bike mastercylinders I have
3 X Nissin Radials all 3/4" piston size and all remote reservoir (Honda and Suzuki)
1 X Nissin Axial with 1/2" piston size and Remote reservoir (From a Honda)
1 X Nissin Axial with 5/8" piston size and Integral reservoir (From a Honda)

I should have a couple more out in the workshop as its not that long ago I upgraded the one on the R6 from a Axial to Radial caliper

[Ghost]

Originally Posted by skidlids

Adjusting the span is just that, making the span fit your hand, if its closer to the bar its easier for you to pull, but doesn't change the amount of fluid you move, that is the same amount of mm travelled by the lever moves the Piston by the same amount as before say you pulled the lever in by 20mm the piston will have moved 4mm no matter where the span is set.

Magura quote a lever ratio of 1 to 5 for the 195 range (the one you have)
and they quote 1 to 7.2 for their 190 range of Radial Mastercylinders.

Brembo figures refer to Piston Diameter and Pivot point position

Had a little look earlier and among my Jap bike mastercylinders I have
3 X Nissin Radials all 3/4" piston size and all remote reservoir (Honda and Suzuki)
1 X Nissin Axial with 1/2" piston size and Remote reservoir (From a Honda)
1 X Nissin Axial with 5/8" piston size and Integral reservoir (From a Honda)

I should have a couple more out in the workshop as its not that long ago I upgraded the one on the R6 from a Axial to Radial caliper

Edited for you Kev. Master

[skidlids]

Originally Posted by Ghost

Edited for you Kev. Master

Cheers Phil, I think I must have used up my Quota of that word for today

Still I have a nice set of PFM 6-pots, narrow track discs and a Radial thingy to go on the R6 this year, If I'm lucky i'll get around to swapping the cylinder head over on the spare engine and may even get that fitted into the bike.

Thinking of going over to the 4-pads on my DD bike, replacing the standard 620 issue 4-pots that are on it at the moment, I need something to try and help me out brake you guys on your lightweight bikes, the Brembo Radial will remain.