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Single disc to dual disc conversion on CB550

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mgilvary:
I've got a '75 CB550 and I'm really not thrilled with the stopping power. I'll be putting new pads on it this weekend, but I've been wondering what it takes to convert it to dual-discs. It seems easy enough to mount a right-side caliper and rotor, but I have no idea how to get a hydraulic connection to the new caliper, given that my stoplight connector only has one output.

Is it as simple as finding a stoplight rig with an extra banjo connection, or is it more complicated than that (like, do I need a different master cylinder?)? And, if it is that simple, where do I find a two-output splitter? Is that something commonly found on a 750?

(Excuse my ignorance -- I'm fairly new at this, but learning fast).

Update: I see there is a section in Home --> Tech Library --> Brakes labelled "Dual Disc Conversion," but I don't see any links to the PDF files mentioned. Anyone know where I can find them?

Zeke:
Hey:

I don't have a 550, but a 650.

My 1980 only had one caliper, and the forks only had brake bosses on the left side.  I inquired about this on the old greenspun site and so maybe some of the info will help you....

I bought a set of forks from a 1982 650 which has brake bosses on both sides -- if you have mounting bosses only on the left perhaps you'll need to find a set of fork legs from a different bike...  Mine cost me about $50.

As far as hooking them up....

I had to buy calipers from the newer model year -- this was easy and I now have two sets of calipers, hoses, and master cyls -- I'll pick the best two of each and go with it.  They were cheap, about $45 total.  But, pretty much everything has to be rebuilt.

There is "T" hardware to split the hydraulics off to the second brake.

The biggest judgement here is whether to try and use your same master cyl or get one designed for dual discs.  A single disc master cyl doesn't move the same amount of fluid volume that a dual disc master cyl does.  So although it may work, you'll have to pull the lever much farther with two brakes than with one.

I like a firm lever, and so this won't work for me.  Some said they didn't mind it but I'm going to get this dual master cyl rebuilt with a new reservoir and do it right.

After all, you're after more stopping power, yes?

Ride On,


Zeke

TRPLE:
I have a CB500 and was likewise disappointed. I ended up buying a braided stainless line for my single caliper. They make a bolt that includes a pressure switch, Dennis Kirk catalog sells it for $15. It just bolts the top banjo into the master cylinder. I think my brakes feel great now. It doesn't increase total braking capacity (only swept are will do that)  but it sure adds confidence.

 - Matt

CB750R:
I have a complete front end from a 77 with dual discs, wheel, and forks.... I bet it doesn't get easier than that....

mgilvary:
Are you just telling me that to rub it in?

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