FZ-07 Arrrrrr Superbike brake caliper project

As I continue to develop my FZ for MotoAmerica, I’m working on the rear brake caliper setup. Robem Engineering makes a nice CNC Billet caliper hanger, relocates the caliper below the disc and uses the Brembo caliper. Saves about 1.5 pounds. Even more when combined with the superlight rotor from Roaring Toyz.

Works great with the OZ or Marchesini R6 wheel, but with the stock R6 wheel, the caliper needs a little machining to clear. Was working pretty good but needed a hair more clearance, and it turned out I took off a hair too much. See pics.

 

So having ruined this caliper, I’m thinking of going all the way. My Pegram 749 RS has a caliper that was cut down, with the hydraulics removed from the backside and the fluid passages plugged. Was done when the 200 was Formula Xtreme rules. Figure it should be good for another 1/4 pound.

What say you, brake gurus?

 

Hah, I made that mistake clearancing a Brembo radial caliper to a spoked Supermoto front wheel... ooops!

 

Couple more pics for good measure.

 

Slap a little JB Weld on it, good as new.

 

My definition of UP must be different than yours.

 

Duh , grind on the wheel some . Less rotating mass !

 

Well you are definitely a racer. The part is clearly marked UP with an arrow and you have it upside down.

 

You should be fine - look at the piston ratio. Don't want a rear brake that will put you down. Better to have one you need to stand on more rather than less.

I've made a lot or rear brake hangers to adapt various calipers to rear wheels over the years: XR650R caliper on a QR dirt track wheel in a Trackmaster frame for Pikes Peak; Cagivia Alazzura for a Verrlichi swing arm; Brembo for Marchesini wheel on a Tigcraft Supermono . . . the list goes on. Mockup for the hanger is critical. I start with the caliper on the disk - fix it where you want it, centered, clearances, etc., (shimming with shim stock of various thicknesses is your friend) - and work out measuring dimensions with the desired hanger configuration. I usually make a heavy cardboard or lightweight wood template before I start carving billets of aluminum. As you have discovered, small changes can make big differences. Once you get what you think you want, try it full forward and full back to make sure you haven't missed something.

It takes time and patience, but it is worth it, as I have discovered the hard way.

Good luck.

Cheers,

Dave

 

Yeah I got that one for free because it was machined upside down.

 

I was lying on my back when I put that on!

 

I’m actually happy with the hanger. I’m going to cut down the caliper to a one working piston setup.

 

Ninja 250 and certain CBR600s have a sliding pin rear caliper. That might be easier to put together than all of the mods required to your current setup.

 

Ummm, I'm not certain I understand your plan. (Not that I need to, but you did post here for input).

Is the plan to somehow block off (weld up?) the fluid passage(s) to the inside pad, thereby making it a one-sided, one piston caliper? If so, how are you going to get the inside pad to float and release? I think this what pscook, supra, is referring to.

One easy solution, if you have another caliper that you want to use along with that desired hanger, is to figure out where/how the new caliper needs to mount (bolt spacing as well as horizontal offset), weld up the bolt holes and adjacent mounting locations, then redrill and tap new mounting holes.

Just a thought.

Cheers

Dave

 

Gino, you should have bob trim a few mm off the radius of the rotor and then make a new hangar to move the caliper in to match. Easy! Lol...

 

Update. Got the caliper cut down the way I want it. Need to trim the bolts and I have a cool little delrin spacer for the caliper pin. All I need to do now is plug the fluid passages. Obviously welding them up would be my first choice. But, since I don't know how to weld and there are no Black Friday specials on welders, I was thinking JB weld. Or as a second option, I could tap fluid passage, put in a stainless steel set screw with JB weld added for good measure.

At least it looks superbikey!

 

Second option for sure, drill and tap. Not a good place for JB.

 

Wasn't life was easier when you raced a clapped out SV?

 

Take it to a machine shop and they can weld up those fluid passage holes in 5 minutes.

 

Does the caliper or the disk float? If not I don't see how that is going to work.