Large or small diameter master cylinder for a single rotor brake setup?

[Rudemouthsky]

As far as an adapter and that billet Brembo 30/34.....
For that money you could get a pair of brand new Brembo 4-pads, a new line, and still have a Benjamin left over.

The advantages I like are:

- Considerable weight savings
- Fully exposed Carrozzeria wheel  
- With a solid billet caliper on the other side  

I don't mind admitting that I care very much about the aesthetics of this bike. However, I do ride pretty aggressively at times, so that is something I'm going to need to keep in mind.

As this is a very experimental setup for me, and I really don't know what to expect, I want the adjustable pivot of the RCS system even more...but those Accossato masters are very tempting.

[Rudemouthsky]

I would likely stick with the OE 4 pad Brembo on the left side, though and save my $ for other mods. That depends on if there's even a marginal performance benefit to the billet caliper.

I guess this thread could be retitled; "how to get the most power from a single rotor braking setup". Since that's what I'm after now...

So here's another query: How do you guys think a Brembo GP/Radial master + single 4 pad caliper/single 320mm floating Braketech Iron disc would fare vs small diameter coffin master + dual OE brembo 4 pots with dual snowflakes in terms of pure stopping power from a given distance at a given speed, with questions of "feel" "sensitivity" etc aside? About the same, better, or worse?

[DarkMonster620]

If, you already have a "2 caliper" master and 2 rotors but NO 4 pad calipers . . . then just get the 4 pad calipers . . . In my eyes, issue solved . . .

Now, if you install that RCS to the 2 piston calipers, you'll be doing endos like the guy who had them on his bike . . . and that guy had the 2 pad/4 piston Goldline calipers with the coffin master that came on his bike . . . even that was a great improvement


Just thinking out loud, sorry if I disturbed anyone's naptime . . .

[Rudemouthsky]

If, you already have a "2 caliper" master and 2 rotors but NO 4 pad calipers . . . then just get the 4 pad calipers . . . In my eyes, issue solved . . .

Now, if you install that RCS to the 2 piston calipers, you'll be doing endos like the guy who had them on his bike . . . and that guy had the 2 pad/4 piston Goldline calipers with the coffin master that came on his bike . . . even that was a great improvement


Just thinking out loud, sorry if I disturbed anyone's naptime . . .

Don't have the rotors yet, and the masters are still brand new in the boxes, fully returnable...

Between a comment Tony made and mistakenly ordering the wrong lines, I'm back to square one with choosing my setup...and I'm really liking the idea of a single rotor if I can put it together to have formidable stopping power and not just good looks..

[koko64]

If you ride real hard and do track days I'm wondering if twin discs would be better (from Lars comment). If you are set on a single disc then maybe a single 4 pad Brembo or ISR 6 pot caliper would give enough bite. The disc and pads would have to be good to resist fading. It seems harder to get Brembo 4 pad caliper pads in organic to suit iron discs from what I've seen, but someone might know a supplier, so that could be a more economical option. For how you say you ride, maybe a 6 pot caliper on an iron disc.
For my peace of mind, if I was running one disc on a hard ridden bike I would want a pretty strong set up.
Speeddog and I ride like gentlemen on the street nowdays .

[Rudemouthsky]

I'm leaning heavily toward the billet 6 pot SIX pad!?! ISR caliper with their recommended billet 14mm master with integrated reservoir. Look at this thing...wow:



Mated with a steel Braketech floater and Galfer green pads (if they make em' for this Caliper)

Nevermind, they have a radial master:

[SpikeC]

  Personally, l think that 2 discs are overkill for most people most of the time. The last time I felt brake fade was  riding switchbacks downhill on my '65 Triumph 500. If you look around a bit you will see some pretty aggressive hot bikes with one front disc. If you use good parts you should be just fine with one.

[Speeddog]

For Lars riding his fire-breathing 800 in the Swiss Alps, yes, a single disc would be a bad plan.  

I'd like to know how ISR defines their 'leverage' ratio, it'd help compare their master-to-caliper size recommendations with Brembo.

The above leverage ratio for a radial lever was using an OEM Duc lever, 848 IIRC.
They make a wide variety of piston diameter x offset masters, so the leverage will vary.

[koko64]

Your path is now clear it seems.

[Düb Lüv]

I was going down this path with the isr stuff before. I talked to a few used to be retailers in the states and braketech. I found out that parts are near impossible, good ideas but the lever feel wasn't as good as brembo, and pad selection is very very limited. There's the pads by isr and maybe 1 type of ferodo. This sucked since I wanted to use a single breaktech iron or cmc rotor. I'm not trying to talk down your ideas it's something I've thought about.

[Rudemouthsky]

Hadn't heard that of the lever feel but then again there aren't too many people running this setup so the sample pool is limited. The guys I buy my parts from said the same thing about them being difficult to work with as far as parts and support goes. They still can order the stuff but they dropped most of it from the website. They did say they loved the product though.

That's exactly what I'm considering, the single caliper and dish out the extra cash for a ceramic rotor since I'd only be buying one. That's all good feedback you're providing and I def need to keep that in mind.

$700 for a billet monoblock caliper is awfully tough to beat though even with those disadvantages in mind.

[Speeddog]

Confirm pad availability for that caliper on an exotic disc before you go too far down that road.

[Düb Lüv]

I was told abou the feel from bellissimoto. Randy said they tried the isr stuff on a few bikes and they were okay. Pita to get products so that's why stopped carrying them. Pro italia was another retailer.

[koko64]

After hearing all that, I would be a little nervous about the ISR stuff. I like good spares back up and easy to deal with suppliers. See what happens when you get old and fearful?
Maybe to play it safe, go the full Beringer single disc kit, or maybe one 4 pad Brembo caliper on a fancy fully floating Brembo disc with the appropriate Brembo radial M/C?

Just when you think you're out, they pull you back in.

[Rudemouthsky]

4 pad Brembo with steel floater would save me quite a bit for other mods...that means more to me than pragmatic concerns like availability of spare parts.