'75 brake upgrade

[PetesPonies]

Being I have been very unhappy with the performance of my stock front brake and I cannot find a decent deal on a drum brake ( would look so much better on my bike ) I have decided to do something about my brake. My MC is not stock, perhaps the reason I am having so much trouble. I do not know the piston size. Anyone here used the new MC that Mike's sells? Is there a bolt on caliper upgrade I could use as well?

 

[TeeCat]

Pete, do you mean the Mike's M/C that's described as "'76-type" and is supposed to be a stock replacement for '72 through '76, I believe? I'm just contemplating ordering one, along with some other stock replacement brake parts, because I want to address my front brake next.

And do you have braided line, or no, if I may ask?

TC

 

[blackbetty]

Can't remember who, but someone on the board tested different size M/Cs and said the 11mm M/C worked best with the 2 piston early calipers. Otherwise there's always the Brembo route.

Here's the brake setup on my '75:

Brembo 4 pot goldline series caliper w EBC sintered pads
Pandemonium caliper bracket
SS custom line from Yoyodyne with two 90* banjos
Brembo 13mm M/C from Yoyodyne

 

[PetesPonies]

TC, yes I believe that is the one. I do have a single braided line now.

 

[PetesPonies]

Ram Jam ( whos knows what I mean ? ) LOL is that a stock rotor?? How much was all of those pieces??

 

[blackbetty]

Hahahaha

You can scour ebay for a Brembo caliper, they come off in pairs and the right side is usually the one in demand for the 35mm kit. I have about $250 in the setup after reselling the right caliper and purchasing new pads. Doesn't look like it's going to work unless you lose or modify the front fender though.

 

[TeeCat]

Pete, I think I'll be ordering that M/C in the next few days, but I'll likely stay with the stock-type rubber hose because it's less fittings for me to have to fuss with trying to size out.

TC

 

[PetesPonies]

I had no problem with the braided line for mine. Everything fit as factory at the caliper as I used the stock solid line and the braided line attached right to it.. I used a banjo type brake switch at the MC . . no problems.

 

[PetesPonies]

and what do those calipers come from?? I mean are they purely aftermarket? or OEM on some bike?

 

[Gordon]

Pete, I believe the guy your looking for is KEV C. He has a real nice set up on his, and he also did the reserch you are talking about. Also, I think INXS posted a chart for master cylinder/caliper size . Maybe Travice moved it to the tech setion, dunno.

 

[Cafe-Dave]

Can't remember who, but someone on the board tested different size M/Cs and said the 11mm M/C worked best with the 2 piston early calipers. Otherwise there's always the Brembo route.

Here's the brake setup on my '75:

Brembo 4 pot goldline series caliper w EBC sintered pads
Pandemonium caliper bracket
SS custom line from Yoyodyne with two 90* banjos
Brembo 13mm M/C from Yoyodyne

That caliper is a Differential Bore caliper that you are running opposite rotation to what it was Designed/Engineered to do.

http://kvickmc.se/brembo-mckatalog/calipers/20680015_25-P430-34F.pdf

You're going to have some very uneven pad wear, along with stresses in the opposite direction as the Forging was designed for. Differential Bore Calipers are designed to be run in one direction, with the Leading Edge of the caliper being the smallest bore which allows the larger bore to "rock" the pad flat as the leading edge tries to dig in more during a braking event. I only mention it to mention it, I mean to insinuate nothing.

It looks like you had to drill out the M10x1.25 threaded features, or am I missing something? The face the Bolt is tightened against is the As-Designed Mounting face.

I personally (Motorcycle Wheel, Brake, Drive Pulley design background) would be hesitant to do the same thing to my XS650B. But if it works well, I am always willing to accept results instead of insults. I am interested to see how well it really stops for you, as I am interested in getting away from the OEM XS650B Brake Silliness.

This applies to similar Tokico/Etc calipers with 65mm mounting lugs and 34mm/30mm bores. Or any Diff Bore caliper.

 

[CDNTX650]

and what do those calipers come from?? I mean are they purely aftermarket? or OEM on some bike?

Anything european

My ducati has twin 320mm rotors and 4 piston calipers.....1 finger slows you down pretty damn fast.

I rebuilt my caliper for my 74, bought the new master cylinder from mikes that they reccomneded, new pads and new rubber lines and it stops pretty damn good now. Especially in conjunction with the rear.

 

[blackbetty]

That caliper is a Differential Bore caliper that you are running opposite rotation to what it was Designed/Engineered to do.

http://kvickmc.se/brembo-mckatalog/calipers/20680015_25-P430-34F.pdf

You're going to have some very uneven pad wear, along with stresses in the opposite direction as the Forging was designed for. Differential Bore Calipers are designed to be run in one direction, with the Leading Edge of the caliper being the smallest bore which allows the larger bore to "rock" the pad flat as the leading edge tries to dig in more during a braking event. I only mention it to mention it, I mean to insinuate nothing.

It looks like you had to drill out the M10x1.25 threaded features, or am I missing something? The face the Bolt is tightened against is the As-Designed Mounting face.

I personally (Motorcycle Wheel, Brake, Drive Pulley design background) would be hesitant to do the same thing to my XS650B. But if it works well, I am always willing to accept results instead of insults. I am interested to see how well it really stops for you, as I am interested in getting away from the OEM XS650B Brake Silliness.

This applies to similar Tokico/Etc calipers with 65mm mounting lugs and 34mm/30mm bores. Or any Diff Bore caliper.

Nice observation, and helpful diagram...could have used one of those a while back!

Anyway, yes, the caliper is oriented with the 34mm piston on the leading end of the rotation, which is not how the caliper was initially designed. I actually called Brembo and had a conversation with a dude at their racing division (Dave?) before I made this mod to see what I can expect out of performance running a caliper backwards.

He told me that uneven pad wear would be the biggest concern; but he also reiterated the fact that this isn't a high speed Ducati we're dealing with, and my bobber certainly isn't a bike I'd feel comfortable slamming through twisties. He also said that running the caliper backwards was negligible in terms or structural impact. So I weighed my options, and at the time of this setup, Mikes wasn't offering a replacement front caliper for 34mm forks. Will the Brembo work? Yea....will it work better than factory brakes? Probably....what's the drawback? Buying $25 pads once a year or so? Not a big deal for me. When I get the thing on the road, I'll report back hahahha, it may completely suck balls for all I know.

The threaded features were indeed drilled out to 25/64ths, the inside lower edge was chamfered for spoke clearance, and the pad guides have to be filed back a bit for rotor clearance. All about 30 minutes of hand filing.

 

[Cafe-Dave]

Nice observation, and helpful diagram...could have used one of those a while back!

http://kvickmc.se/brembo-mckatalog/

That should help a little more.

Anyway, yes, the caliper is oriented with the 34mm piston on the leading end of the rotation, which is not how the caliper was initially designed. I actually called Brembo and had a conversation with a dude at their racing division (Dave?) before I made this mod to see what I can expect out of performance running a caliper backwards.

He told me that uneven pad wear would be the biggest concern; but he also reiterated the fact that this isn't a high speed Ducati we're dealing with, and my bobber certainly isn't a bike I'd feel comfortable slamming through twisties. He also said that running the caliper backwards was negligible in terms or structural impact. So I weighed my options, and at the time of this setup, Mikes wasn't offering a replacement front caliper for 34mm forks. Will the Brembo work? Yea....will it work better than factory brakes? Probably....what's the drawback? Buying $25 pads once a year or so? Not a big deal for me. When I get the thing on the road, I'll report back hahahha, it may completely suck balls for all I know.

I tend to agree. It'll be better than what was on there, and it's not like you're going to be abusing a vintage motorcycle with spoked rims by mounting that caliper.

Don't buy new pads. Just take them out once or twice a year and Flip the Inners for the Outers. I'd suspect that'd be good enough. It'll give you the opportunity to clean up the system and hose everything down with brake cleaner and a soft bristle brush (like I'm the only one that uses a well-worn toothbrush on his Caliper Pistons....)

The threaded features were indeed drilled out to 25/64ths, the inside lower edge was chamfered for spoke clearance, and the pad guides have to be filed back a bit for rotor clearance. All about 30 minutes of hand filing.

Good to know. For the results you get, minor work like that should be worth it

Personally, I've been interested in using x2 of the Brembo P32F calipers. They may wind up looking somewhat OE, but new. Also will be able to use some current braided lines, new hardware, etc. Won't be able to run the OEM Fender (not a concern). The intent is to find Rotors that will replace the OE components and allow a dude to run dual discs with brand new OTS parts.

http://kvickmc.se/brembo-mckatalog/calipers/20516142-P32F.pdf

http://cgi.ebay.com/ebaymotors/DUCA...ccessories&hash=item19c6c0db07#ht_4549wt_1011

Simply because a LH/RH Positionally independent bracket may be able to be designed. I have not even taken the wheel off my XS650B and measured the mounting lugs, I may get on that in a few weeks after tearing into the wiring. We'll see how bad Feature Creep and Analysis Paralysis contributes

My goal is to have a neat setup, I may have to call some favors in with http://www.qtmi.com/ for part numbers and ordering parts. That is a great company to do business with, great people and it's a very neat operation. Cannot say enough good things about them, one of the things I honestly miss about living in SoCal.

Good luck with your project.

 

[CDNTX650]

(like I'm the only one that uses a well-worn toothbrush on his Caliper Pistons....)

just did the 999 and klr over winter. hahaha

 

[blackbetty]

http://kvickmc.se/brembo-mckatalog/

That should help a little more.



I tend to agree. It'll be better than what was on there, and it's not like you're going to be abusing a vintage motorcycle with spoked rims by mounting that caliper.

Don't buy new pads. Just take them out once or twice a year and Flip the Inners for the Outers. I'd suspect that'd be good enough. It'll give you the opportunity to clean up the system and hose everything down with brake cleaner and a soft bristle brush (like I'm the only one that uses a well-worn toothbrush on his Caliper Pistons....)



Good to know. For the results you get, minor work like that should be worth it

Personally, I've been interested in using x2 of the Brembo P32F calipers. They may wind up looking somewhat OE, but new. Also will be able to use some current braided lines, new hardware, etc. Won't be able to run the OEM Fender (not a concern). The intent is to find Rotors that will replace the OE components and allow a dude to run dual discs with brand new OTS parts.

http://kvickmc.se/brembo-mckatalog/calipers/20516142-P32F.pdf

http://cgi.ebay.com/ebaymotors/DUCA...ccessories&hash=item19c6c0db07#ht_4549wt_1011

Simply because a LH/RH Positionally independent bracket may be able to be designed. I have not even taken the wheel off my XS650B and measured the mounting lugs, I may get on that in a few weeks after tearing into the wiring. We'll see how bad Feature Creep and Analysis Paralysis contributes

My goal is to have a neat setup, I may have to call some favors in with http://www.qtmi.com/ for part numbers and ordering parts. That is a great company to do business with, great people and it's a very neat operation. Cannot say enough good things about them, one of the things I honestly miss about living in SoCal.

Good luck with your project.

You're sharp man, I wish you were around when I was putting this all together. I had to call around all over the place to put together my info. I even had to ship my rotor to Dan at pandemonium so he could come up w a prototype bracket for the 34mm forks and the brembo caliper.

I think your idea to use the P32F calipers is perhaps the best Brembo solution if one is looking to do a dual rotor setup; I wonder how it would perform using just a single caliper to reduce weight? 2 32mm pistons should probably provide a more modern feel against the early style 2 piston XS calipers....

Keep us in the loop on whatever you do. I love seeing front brake solutions for the older XS's.

 

[PetesPonies]

CDNTX650 . thanks for your input. This was the easy way to go . I new and more proper MC. I was wondering how it worked and you seem to be happy with it. If you look at my gallery, you'll see this isn't a bike for the twisties either and just having a good feeling when I stop is what I am after.

 

[CDNTX650]

compared to the stock one on my honda 500/4 that was not refurbished this works reaaally good. haha.

i agree, and combined with a well setup rear drum, the bike stops pretty good.

i really like the brembo idea, but it will be on my next one thats real custom. i don't wanna lose my front fender.

 

[PetesPonies]

I ended up ordering a 13mm MC. That should apply more force to the pads, albeit with a bit more stroke.