Larger rotor with Brembo 4 pot caliper

[subxero]

quick part list.

This rotor, not necessarily from this seller.
Advertised as Ara Shi 320 mm free float for ninja250. Direct bolt on. Not sure if 320mm though? need to measure it i guess?
http://www.ebay.com/itm/151239856301...84.m1497.l2649

Any Brembo 65mm 4 pot caliper, tons of late 90's early 2000's ducati's had these. I got mine off of 2001 748. Guy on ebay from UK sells referbished pair for like $250, maybe contact him, he might sell you just the right caliper? You can find cheaper though. Just recently saw a pair for like $80
here is link to referb ones
http://www.ebay.com/itm/Ducati-748-9...item2331cadd87

2 M10x1.25pitch bolts for the caliper, i will measure them tonight. can't remember what i ended up with. 35-40mm should work fine over 40mm might be to long

2 M8x?? pitch bolts to mount the bracket to the fork. Will be same pitch as stock bolts here but will need to be 0.25" longer than stock & is 36mm long so around 42-43mm might have to cut your own as there is little room for them to be to long.

Other hardware you would need for caliper if they did not come with it. M10x1.00 banjo bolt, bleeder screw, brake pads ect... I bought new caliper bolts from that UK guy to freshen up my caliper for like 10 bucks.

Then you will either need to take apart your take off OEM brake caliper, and remove the mounting plate piece and hack the lobes off it as you will still use this to screw the bracket to forks into. Other route is buy one cheap off ebay and hack that one if you want to keep your OEM brake intact.

Again, once i get a camera, maybe tomorrow, i can get some pics maybe Sunday, or Monday.

Got a lot going on the next few days so Sunday is the best bet, i still need a road test but i have no concerns about that. only concern is how brakes feel, is the MC enough? should be.

I might be in for the GB just to get the latest update on the bracket with the .02" thicker section for a little more clearance. Better safe than sorry.

[verboten1]

I would be in, pending cost

[Bigballsofpaint]

If enough people actually want this ill send you the new one for free, dont sweat it. For pricing im thinking

5 people or less - 50 shipped
less than 10 people - 45 shipped
10+ - 40 shipped

How about that? if that sounds OK then ill make a seperate thread in the for sale section in the next few days as to not clutter this thread

[subxero]

^ not to give you any ideas but your prices look good check these out.

over $150/pair

http://www.yoyodyneti.com/category.aspx?categoryID=2954

This whole set up cost me
$150 for rotor
$80 for caliper (what i got mine for, Keep an eye open and you can find one at this price, they go fast though on ebay)
$10 for Ti banjo bolt
$10 bolt kit for caliper
Few bucks for random bolts (gonna upgrade them though)
$45 new pads
Cost of bracket from Bigballsofpaint

Like i mentioned before, if you are in the market for a new rotor and pads then it is really not much at all

[sharky nrk]

For less than $50 I bet I am in.

[verboten1]

Originally Posted by Bigballsofpaint

If enough people actually want this ill send you the new one for free, dont sweat it. For pricing im thinking

5 people or less - 50 shipped
less than 10 people - 45 shipped
10+ - 40 shipped

How about that? if that sounds OK then ill make a seperate thread in the for sale section in the next few days as to not clutter this thread

That sounds like a reasonable price point to me, the brackets I made for my virago priced out right around there for the pair (way less complicated)

[Bigballsofpaint]

Ill still wait for Joe to test it out, i will prob make a thread on memorial day for it.

[subxero]

Sunday at the earliest. Monday at latest.

[bruce71198]

Originally Posted by subxero

quick part list.

This rotor, not necessarily from this seller.
Advertised as Ara Shi 320 mm free float for ninja250. Direct bolt on. Not sure if 320mm though? need to measure it i guess?
http://www.ebay.com/itm/151239856301...84.m1497.l2649

Any Brembo 65mm 4 pot caliper, tons of late 90's early 2000's ducati's had these. I got mine off of 2001 748. Guy on ebay from UK sells referbished pair for like $250, maybe contact him, he might sell you just the right caliper? You can find cheaper though. Just recently saw a pair for like $80
here is link to referb ones
http://www.ebay.com/itm/Ducati-748-9...item2331cadd87

2 M10x1.25pitch bolts for the caliper, i will measure them tonight. can't remember what i ended up with. 35-40mm should work fine over 40mm might be to long

2 M8x?? pitch bolts to mount the bracket to the fork. Will be same pitch as stock bolts here but will need to be 0.25" longer than stock & is 36mm long so around 42-43mm might have to cut your own as there is little room for them to be to long.

Other hardware you would need for caliper if they did not come with it. M10x1.00 banjo bolt, bleeder screw, brake pads ect... I bought new caliper bolts from that UK guy to freshen up my caliper for like 10 bucks.

Then you will either need to take apart your take off OEM brake caliper, and remove the mounting plate piece and hack the lobes off it as you will still use this to screw the bracket to forks into. Other route is buy one cheap off ebay and hack that one if you want to keep your OEM brake intact.

Again, once i get a camera, maybe tomorrow, i can get some pics maybe Sunday, or Monday.

Got a lot going on the next few days so Sunday is the best bet, i still need a road test but i have no concerns about that. only concern is how brakes feel, is the MC enough? should be.

I might be in for the GB just to get the latest update on the bracket with the .02" thicker section for a little more clearance. Better safe than sorry.

Would you please post some photos of you set up? Thanks.

[mgentz]

Check page 2

[mgentz]

Ok....here

Originally Posted by subxero

as promised, some crappy pictures. I hope to get a new digital camera before this weekend so I will update with better pics next week.

These are taken at night, with no light on my busted camera phone.

I will probably look for some fancy bolts to clean it up a little bit. Maybe some gold Ti race spec bolts or even just steel race spec, IDK? something, anything will look better than just regular old bolts

Still need a road test but should be non issue. Might have to go to larger master cylinder if I don't like feel of brakes. I need to go feel some brakes on some nicer bikes first though.

Now that this is pretty much GTG I can maybe put together a DIY with everything laid out. Pretty easy really.

[subxero]

Ill get some good pics up a little later today, tonight at the latest.

Got everything back together this morning and went for a short cruise. Again lots of new things so hard to say much about anything in particular. New tire, new brakes/rotor, had to take things easy to bed/scrub things in.

^this being said, mechanically everything works perfect, no issues what so ever with anything. The one problem that i seem to have is that my front brake is a little soft at this point. I will bleed them again here in a little bit after i give her a quick bath to see if i get any more air out but i am thinking i will have to go to a larger MC to get the best feel which only makes sense as the stock caliper is a small 2 pot.

The foot print on the rotor looks great, could be the tiniest bit better. IF the caliper sat literally 0.02" more to the outside. This adjustment could be made to the mounting bracket using math/trig whatever to move caliper holes a little bit... however i will not be doing it. I am thinking it would also be more work for Jay as well as lots of other numbers would change.

Haven't done anything to the mounting bracket yet. Might paint it black, might not, IDK?

Either way i love the way the new rotor and caliper look on my 12' black SE

Pics up soon! I got a new camera on Friday so no more ****** cell phone pics

Edit: if anyone knows of any swappable larger MC's from other bikes let me know. I'm on the hunt and doing some research

[bruce71198]

No need to post more picks if you don't want to. I overlooked the ones on page 2. Do you know what the bore diameter is in the stock MC? I know some people use a stock R6 Brembo.

[subxero]

Originally Posted by bruce71198

No need to post more picks if you don't want to. I overlooked the ones on page 2. Do you know what the bore diameter is in the stock MC? I know some people use a stock R6 Brembo.

was gonna post some better pics regardless. From what i have read in various places here, stock MC is 13mm

[subxero]

here some some pics from the photo shoot today.

Again, i may or may not paint it. I have one of the scraps, i might paint it black to just get an idea of looks, if i like it, then paint the good one as well, if not keep good one as is with a clear coat.

Might put some gold colored bolts on there as well, think it would look nice with the bare metal.

[Motofool]

Originally Posted by subxero

here some some pics from the photo shoot today.........

[sharky nrk]

looks great, whats the piston size on the caliper? I am interested in the feel improvement more than anything and the stock caliper/master combo blows even with good pads and lines in terms of feel. I know alot of people thing the stock master is a little big for the stock caliper.

[choneofakind]

Good looking bike joe, I don't think I'd ever seen it before. The caliper looks great as well.

[Aggrotech]

nice pics. Would you be able to get a pic from above the caliper facing down towards the brake pads/rotor, jus to see how much clearance there is with teh new pads?

[Bigballsofpaint]

Joe, just let me know what you mean by move .02 to the outside. If you mean the .58 thickness to .6, thats an offset change. Even if its a directional change, let me know. it would be simple.

[Somchai]

Wow, that looks great

[subxero]

Originally Posted by Bigballsofpaint

Joe, just let me know what you mean by move .02 to the outside. If you mean the .58 thickness to .6, thats an offset change. Even if its a directional change, let me know. it would be simple.

No not that. I mentioned early to increase the 0.58" to 0.60 and that will center the rotor a little better between the pads in the caliper

The 0.02 i mentioned a few posts ago is to change the placement bite of the pads on the rotor. Would be a little more tricky as the actual holes would have to get moved. I'm sure i could figure it out, but just don't feel like messing with it any more and it is really non issue. If you look at some of the closer pics you can see on the rotor where the pads are contacting. On the outside there is maybe 2mm of un touched rotor. But on the inside it is almost dead even with the inner diameter of the meat of the rotor. Again it is non issue and i don't see it helping anything, is more of a nit pick thing than anything

[subxero]

Originally Posted by Aggrotech

nice pics. Would you be able to get a pic from above the caliper facing down towards the brake pads/rotor, jus to see how much clearance there is with teh new pads?

what clearance are you looking for? Between what and what?

The only thing that is remotely close is as i mentioned earlier. The cast part of the caliper it's self has guides on the inside of the caliper. The inside side of the rotor is fairly close to the guide on that side of the caliper. I submitted a change to Jason to help with this and it should be easy peasy and all brackets from here on out should come with the change. My bracket worked fine today, no problems so this change would be just to give a little bit more clearance for expansion ect...

[bruce71198]

Originally Posted by subxero

was gonna post some better pics regardless. From what i have read in various places here, stock MC is 13mm

I think 13mm is to small for that size caliper. It will give you lots of braking power and also a lot of lever travel. That may lend to the mushy feel. 16 mm should be more in line with what the Duc had on it.

[sharky nrk]

Originally Posted by bruce71198

I think 13mm is to small for that size caliper. It will give you lots of braking power and also a lot of lever travel. That may lend to the mushy feel. 16 mm should be more in line with what the Duc had on it.

but did the Duc has two sets of calipers it was moving pistons on? best way to know if to just compute the piston area

[rojoracing53]

I heard somewhere that the piston size effect or radial MC vs Standard MC(stock) is different, like if you had 13mm for both the feel would be totally different because of the lever pivot.

I'm running a brembo 15mm radial and its perfect for single 4 pots setups. Brembo made two models of this MC, a 19mm for the Superbikes with dual 4-6pot systems and a 15mm for supermoto bikes with single 4-6 pot systems. I can also change the cam point by a few degs and it give the lever a much stiffer feel.

I originally tried a brembo 20mm GP style MC and the level was so stiff it didn't move at at past pad contact but at the same time no matter how hard you pulled it felt like the pads wouldn't grip because you had no leverage. There's a fun balance but I can confirm a 15mm radial setup will be perfect or at least very close to what you want.

[sharky nrk]

15RCS if I am not mistaken ^^^

very nice piece

[rojoracing53]

Originally Posted by sharky nrk

15RCS if I am not mistaken ^^^

very nice piece

Yes

[subxero]

just looked into those, pretty sweet. I will probably pull the trigger on one today or tomorrow when my credit card statement rolls over that way I don't have to actually acknowledge how much it cost for a month

Clearly for other people interested in the caliper mod there would be much cheaper ways to go but I figure at this point WTF not?

go big or go home right?

[rojoracing53]

An OEM MC off a single caliper KTM or husky would probably do the trick and would most likely still be brembo brand OEM production. What ever you do just make sure you get an MC with its own topside bleed nipple, its makes you life much easier when getting that perfect bleed.

[mgentz]

just remember that the brake line will need to be modified or else it will stick out oddly. probably will work, but you should be aware.

[rojoracing53]

Originally Posted by mgentz

just remember that the brake line will need to be modified or else it will stick out oddly. probably will work, but you should be aware.

^This

Your going from a vertical mount to a horizontal so you'll need a completely different upper fitting style.

[bruce71198]

Originally Posted by sharky nrk

but did the Duc has two sets of calipers it was moving pistons on? best way to know if to just compute the piston area

Keep in mind that I am not an engineer nor have I seen one on TV. According to Pascals theory on pressure: fluid pressure in an enclosed area will be equal and undivided in all directions. Or something to that effect. I take from this that given a certain sized MC it will give the same braking force to each caliper regardless of how many calipers there are. In practice I have experienced adding calipers to a front brake system and found that:1) brake power was increased due to an additional brake rotor and caliper. 2) normal lever feel didnt change much. 3) lever travel increased a little. So what I'm getting at is whatever diameter piston the original Duc MC had should work here.

[sharky nrk]

Originally Posted by bruce71198

Keep in mind that I am not an engineer nor have I seen one on TV. According to Pascals theory on pressure: fluid pressure in an enclosed area will be equal and undivided in all directions. Or something to that effect. I take from this that given a certain sized MC it will give the same braking force to each caliper regardless of how many calipers there are. In practice I have experienced adding calipers to a front brake system and found that:1) brake power was increased due to an additional brake rotor and caliper. 2) normal lever feel didnt change much. 3) lever travel increased a little. So what I'm getting at is whatever diameter piston the original Duc MC had should work here.

lol for what its worth I am an engineer but have spent many years in management dulling my formula memory, but in the simplest form F=pressure/area and for the same fluid pressure, half the piston area doubles force exerted at the piston face. Pressure in a closed system in generated by the force generated as input to the lever on the piston of the m/c, with variables be lever pivot moment and piston size of m/c.

[bruce71198]

Originally Posted by sharky nrk

lol for what its worth I am an engineer but have spent many years in management dulling my formula memory, but in the simplest form F=pressure/area and for the same fluid pressure, half the piston area doubles force exerted at the piston face. Pressure in a closed system in generated by the force generated as input to the lever on the piston of the m/c, with variables be lever pivot moment and piston size of m/c.

Isnt that what I said?

[sharky nrk]

Originally Posted by bruce71198

Isnt that what I said?

The way it read to me in your post was that the internal system pressure being equally distributed across the surface area of the pistons would keep things relatively equal in either a single or dual caliper setup. That would be making the assumption that internal fluid pressure = resultant force, which is only true if applied surface area is the same. In the case of your caliper comment, using the same master (one designed for two calipers) in a system with a single caliper would have the internal fluid pressure acting across half of the surface area (half the pistons) for the same stroke. This would be a significant difference in applied force and in turn lever and brake feel.

[sharky nrk]

Originally Posted by bruce71198

3) lever travel increased a little. So what I'm getting at is whatever diameter piston the original Duc MC had should work here.

specifically don't do this as it could cause you to have too hard a lever, with too little travel, and too little modulation

[bruce71198]

Originally Posted by sharky nrk

specifically don't do this as it could cause you to have too hard a lever, with too little travel, and too little modulation

Ok. So I dont have the aptitude to figure out on paper mathematically what size MC to use. Lets say the original Duc had 2 calipers and a 16mm MC bore. If you remove one caliper what size MC bore should you use? That sounds like one of my sons math questions, that I cant help him with.

[sharky nrk]

Originally Posted by bruce71198

Ok. So I dont have the aptitude to figure out on paper mathematically what size MC to use. Lets say the original Duc had 2 calipers and a 16mm MC bore. If you remove one caliper what size MC bore should you use? That sounds like one of my sons math questions, that I cant help him with.

Honestly its going to depend a little on a couple of variables that we may or may not have and kinda going to have be a little shot in the dark. It looks like the 15mm master posted above was pretty decent for a single 4 piston caliper.

But that is alot of coin for a m/c too. Take a yamaha for instance, 16mm oem brembo m/c pushing two sets of calipers that have 27 and 30mm pistons. That ratio seems to work well for that setup with a pair of calipers. The Ducati bits look like they are 34 30mm piston combo. Which means that the Ducati caliper has aroud 25% more area in the pistons than the yamaha.

So putting the ducati calipers on the yamaha would give a longer travel softer lever. The kicker is your cutting the caliper count and therefore the area in half. So if you look at the pair of yamaha calipers, they have 58% more area than a single ducati caliper. So my guess is a 13-15mm master given lever ratio is the same between masters.

[sharky nrk]

ok so one more shot with actual maths

using yamaha setup as a base setup. Two sets of calipers, 27mm and 30mm pistons in calipers, 16mm radial master. 5115.06 mm^2 piston area in caliper, 200.96 mm^2 piston area in master. A 25.45 to 1 ratio

single ducati caliper, 30mm and 34mm pistions, total caliper piston area 3227.92 mm^2, for the same 25.45 to 1 ratio you would need 126.82 mm^2 master piston area. This would be a 12.7mm master cylinder piston. Not a normal size but damn close to a 1/2 inch master which is readily available.

Go up if you want firmer lever with less travel but likely harder to modulate. Go down if you want more travel at the lever with less firm bite.