When I fitted the 1098 forks into my 999 I picked up these front Calipers from somewhere, but can't remember where I got them from, or what they came off. They are the ones with the 4 small pads and have 4 x 35mm pistons, I think. Any idea what they could have come off? Anyway, why am I asking now several years down the line? I kept the original 999 Front master cylinder, which is 18mm, but I've never been really happy because there is hardly any movement at the lever and very little feel. I've noticed that the 999 master cylinder is actually weeping a little now, so it's an obvious opportunity to change it for something that may give a little more feel. If I knew what the Calipers were off I could target a master cylinder from that bike on Ebay. Does anyone know what bore size master cylinder those Calipers should be partnered with? What options do I have with regard to a suitable Master cylinder in 17mm or 16mm? What bikes come with that Master cylinder? In other words, does anyone have an encyclopaedic knowledge of Ducati/Brembo Brake Calipers, Master Cylinders, and what models they fit? Thanks
these calipers were fitted to the BMW S1000RR and depending on variations over the years, here is the master cylinder:- (2013 - more research will tell you the bore/stroke) you are welcome...
My guess is 999R. https://www.ebay.co.uk/itm/22698723...iGPz8yESqmeLzJKtfuB7R0kQ==|tkp:Bk9SR4aGj8mdZw. Andy
From AI:- The 2023+ BMW S1000RR features a stock front brake master cylinder with a 17 mm piston bore. Upgraded or aftermarket options (like the Brembo RCS Corsa Corta) commonly use a 17 mm or 19 mm bore, with the RCS systems providing adjustable pivot distances (stroke/ratio) of 18 mm or 20 mm for personalized braking feel.
Thanks all. Trawling ebay it looks like the 18mm Master cylinder is really common for Ducati models, but some later bikes have a 16mm. I've not considered other manufacturers at the moment, and do want to keep the non-remote type reservoir. So, are the Calipers I have anything special? If they are fitted to the 999R. I'd be surprised if I paid a lot of money for them, but perhaps that's where my mismatch lies rather than the master cylinder. I could always buy a set of less expensive Calipers and sell what I have on, because I really don't need anything too special for what I do with the bike. The lack of feel and no lever movement at the moment makes it harder to ride and is possibly more dangerous than a pair of more normal calipers, if that's where my issue lies.
Did I sell you these? I believe tuono if you had them off me. I have the same in black on the 749 track bike, off a 990 ktm.
I assume these are what's known as Monoblock Brembo Calipers. I might swap them for a set of conventional Calipers I think I have hanging around and see if the feel is any better. If so I'll swap the Master Cylinder for another 18mm one and sell on the Monoblocks.
I found those calipers had bags of feel on my 749R - not sure what the master cylinder diameter is but I would go with same as the R.
Calculate your brake ratio and optimise it: Determine the sum total area of your caliper pistons then divide that figure by the area of your master: Soft feel — 30:1 Best feel — 27:1 Firm feel — 23:1 Wooden — 20:1 Personally I love around 25:1 which is a 19mm master with the 34mm caliper pistons By the way - how do you buy pads if you don't know the type of caliper?
It's about 30:1, but the lever hardly moves, the brakes are either on or off and the lever feels solid. But with no pressure on the lever the wheel runs really freely with no drag. I just brought the pads that come as a set of 4 rather than 2 per caliper.
That's quite strange, at 30:1 you should be in one finger lockup territory.. Better do some checking / measuring / servicing...
Are they Monoblock construction? i.e. a one-piece construction or a two-piece that split down the middle/bolted together? Because they don't look like the M4 Monoblock as fitted to 1098 etc. I have the M4 Monoblocks on my Monster, they are great calipers with plenty of power but are more 'grabby' than the Brembo HPK on my 916, especially with regards to the initial bite that said, they still have plenty of feel as long as you don't grab too much of a handful at first. To add, I'm using 19mm Brembo radial master cylinders on both bikes, fixed ratio 19x20 on the 916 and RCS 19 with switchable 18/20 ratio on the Monster and both are 2-finger braking with as much power as you would ever need, the HPK are definitely more progressive though.
Thanks Guys. They are Monoblock, in that they are a single piece cast and machined without a split down the middle, but I'll defer to RickyX's far superior knowledge that they are not M4's as I don't even know what that means.
They are Brembo P4, 32/34mm pistons. I used a set from BMW on my multistrada, used a 18 RCS master cylinder.
