Brake Capacity and Dual Front Discs

[bdholsin]

I've noticed that my '83 is a little slow to stop. I really have to clamp down on the binders in addition to engine braking. I'm definitely not driving too fast...just observing that it takes more force on the front (disc) and rear (drum) to stop. I had rebuilt the master cylinder and know that there isn't any air in the line.

Would stainless braided lines provide any additional brake capacity?

If braided stainless doesn't do it I have already convinced myself that I'll put a second disc up front. I now have a second disc (thanks mfrad). I've been looking at Mike's web site and see that I'll need an additional caliper (I'll just order a pair and replace the old one as well for piece of mind), pads, large volume master cylinder and the appropriate lines.

Has anyone done this and if so any suggestions? This'll most likely be a winter project and be ready for the spring. I think I'm in the unfortunate situation that I got this bike ready and running just in time to put it away.

Thanks.

 

[gordonscott]

Would stainless braided lines provide any additional brake capacity?

If braided stainless doesn't do it I have already convinced myself that I'll put a second disc up front. I now have a second disc (thanks mfrad). I've been looking at Mike's web site and see that I'll need an additional caliper (I'll just order a pair and replace the old one as well for piece of mind), pads, large volume master cylinder and the appropriate lines.

Thanks.

Hi, Stainless lines will do the trick You don't need to add a second caliper and rotor unless you like the look, it's a lot of upsprung weight added. Get quality lines from "Russell" or "Goodridge, not the cheap stuff made for the xs. You can buy the lines any length and just add fittings, all parts here....
http://www.denniskirk.com/jsp/tpl/c...y=215,21503&brandId=314,658&_requestid=652539 There is a reason I say to go with "Russell or Goodridge", I have used both the xs made stuff (China) and brand names, trust me go with brand names

 

[bdholsin]

Excellent (best imitation of Montgomery Burns from the Simpsons). Thanks gordonscott.

 

[gordonscott]

Excellent (best imitation of Montgomery Burns from the Simpsons). Thanks gordonscott.

No problem my friend, let us know

 

[Motrhedd]

my front brake was weak as well on my 83,I switched to a 86 kawi zx master [looks alot better too] braided line[jireh cycles 24 dollars for line about 10 bucks for fittings],drilled the rotor and installed ebc pads,Works great now

 

[bdholsin]

I'll be taking brake line measurements and making an order this winter.

 

[XSLeo]

I have found that the stock 14 mm calipers on the later bikes works very well with a dual disc set up. It's a bit to big for a single disc set up.
An 11 or 12 mm M/C will feel much better than the 14 mm. The lever travel will be a bit more but it will pull easier and this extra leverage makes the caliper grip the rotor much better.
Swapping the rotor for slotted rotor from an XS1100 will improve the braking even more. Dilling your stock rotor will do the same thing. A drilling pattern and a drill press is all you need to drill them. Look in the tech section here I think they have information there.

 

[Capt_Zoom]

Goodrich lines will do the trick. THese bikes are so light (especially if its chopped/hardtailed) that running dual front doesn't make that much difference. SS lines are great. I put them on my raider (700lbs already with dual front) and you can immediately tell the difference.

 

[bdholsin]

So now that I'm going to go with the braided SS brake line I have a question. The current brake line is in two pieces. The first piece goes from the master cylinder to some sort of a "manifold" (I call it a manifold for no better term) on the front suspension. After the "manifold" a second section of brake line goes to the caliper.

My question is: Can I eliminate the "manifold" and just run one piece of braided SS line from the master cylinder straight to the caliper?

I can't think of a reason that I can't do it but need confirmation from the seasoned veterans here. I'm guessing that the "manifold" is there in the event that I upgrade to dual discs down the road (which may be a possibility of the braided SS lines don't fix the braking capacity).

Thanks!

 

[Capt_Zoom]

The manifold is if there was a break tee there for dual disc brakes. Just run a line from your master cylinder down to you brake. An easy way to measure is to lift the front of the bike run an extension cord of similar thickness from your brake up to the bars in the way you want to mount it. Attach it with zip ties and move the handlebars back and forth to get your min length. If you're going with Goodrich one piece lines tell them that this is your total length including the crimped fittings. If you're going with the kits the fittings are not included in the line length. Most of the fittings are between 3/4 and 1.25 inch long depending on what your using so calculate accordingly.

 

[bdholsin]

Excellent. Thanks Capt.

 

[Capt_Zoom]

Personally, I suggest using the kit. I think they look a little better appearance-wise. Not as sleek but the chrome is definitely better and if you mess up your measurements you just return it and get a new line. You mess up on the custom one-piece jobs and your stuck with it.

 

[bdholsin]

That's what I was planning. Using a kit is the way to go...just need a final dimension, remove the old and drop in the new. Then I'm ready to bleed the air. Shouldn't take more than about 10 minutes to do.

 

[atomic22]

Would you mind sharing what kit you are going with?

 

[gggGary]

Plan on an overhaul of the front caliper and master cylinder as long as you are breaking the seal. I haven't opened one up yet that didn't need thorough cleaning at least and a good rust free caliper piston is rare at least here in the midwest. Personally it's must on any old bike I am going to ride very far. I have yet to strip down an old brake system and say I didn't need to do this.

Reread the top post and see you did the master, how about the caliper?

 

[xjwmx]

Yep, the caliper piston will rust and let air in After rebuilding everything and adding steel lines (although a type Gordon warns against and I don't blame him) I can skid the front tire, with a real hard squeeze.

Also, if you need to stop fast, it's recommended to pull the clutch. The bike can slow faster than the engine can, so in the case of trying to stop fast the engine works like a flywheel keeping you moving.

 

[bdholsin]

Plan on an overhaul of the front caliper and master cylinder as long as you are breaking the seal. I haven't opened one up yet that didn't need thorough cleaning at least and a good rust free caliper piston is rare at least here in the midwest. Personally it's must on any old bike I am going to ride very far. I have yet to strip down an old brake system and say I didn't need to do this.

Reread the top post and see you did the master, how about the caliper?

I did take a look at the caliper when I rebuilt the master. The piston wasn't too bad but will get some attention when I have the money.

Yep, the caliper piston will rust and let air in After rebuilding everything and adding steel lines (although a type Gordon warns against and I don't blame him) I can skid the front tire, with a real hard squeeze.

Also, if you need to stop fast, it's recommended to pull the clutch. The bike can slow faster than the engine can, so in the case of trying to stop fast the engine works like a flywheel keeping you moving.

I haven't skidded the front tire yet although I have only put about 50 miles on the bike since getting it running. I do tend to use some engine braking when necessary in addition to the front and rear brakes. Dropping gears uses the lower gears and the engine becomes a vacuum pump at higher speeds.

Would you mind sharing what kit you are going with?

As soon as I have that figured out I'll update this thread. Can't seem to find my measuring tape (think one of my sons ran off with it) to take measurements.

 

[atomic22]

Plan on an overhaul of the front caliper and master cylinder as long as you are breaking the seal. I haven't opened one up yet that didn't need thorough cleaning at least and a good rust free caliper piston is rare at least here in the midwest. Personally it's must on any old bike I am going to ride very far. I have yet to strip down an old brake system and say I didn't need to do this.

Reread the top post and see you did the master, how about the caliper?

Gary would you recommend the rebuild kit from MikesXS?

Hi, Stainless lines will do the trick You don't need to add a second caliper and rotor unless you like the look, it's a lot of upsprung weight added. Get quality lines from "Russell" or "Goodridge, not the cheap stuff made for the xs. You can buy the lines any length and just add fittings, all parts here....
http://www.denniskirk.com/jsp/tpl/c...y=215,21503&brandId=314,658&_requestid=652539 There is a reason I say to go with "Russell or Goodridge", I have used both the xs made stuff (China) and brand names, trust me go with brand names

Gordon, what lines/kit would you recommend?

Thanks

 

[gggGary]

Gary would you recommend the rebuild kit from MikesXS?

I haven't used one. But I will probably try the pistons soon. I have a tub with about 15 disassembled XS650 brakes and select and clean the best parts and reassemble. Not everyone has that option though. So yeah best is a kit. As bad as the pistons often are ( I have had to use the grease gun removal method a bunch of times) the rubber seal always looks great. But that is from the mid west where dry heat doesn't eat rubber parts. On master cylinders it's about the same I try to pick the best one I have disassemble, hone the bore, and reassemble. but if you need a kit probably makes $ense to buy a new chinese fleabay master cylinder.

 

[xjwmx]

I used Mike's master cylinder kit and caliper kit and caliper piston. No problems at all.

I didn't have to hone anything. If you do, remember it's aluminum.