Dual Disk on 1977 Z650

I know this topic has come up several times (I used the search function!)..

I have found some very useful information, including this guide: z650.proboards.com/thread/68

But it still left me wondering..

Can't I just get a second disc and caliper from a 1977 Z650?

I know they are 7mm as opposed to the thinner 4-5mm dual discs usually are, but I don't mind as long as it all fits. And I don't mind not switching the forks around, if that's the only way it will work or something.

I found a good deal on a '77 Z650 rotor and caliper, and I would like to go that route if possible.

Thanks all!
-Stephen

Switching the forks around isn't a good idea because your fender stay mounts will be facing forward rather than toward the rear.

Also, be careful about which way the bleeder valves face. There is a left caliper and a right caliper - they are not the same. Ed

+1
It seems like it should work but it doesn't .......that bleeder valve is the issue.

you could bench bleed the caliper. However, i agree with the others that its best to find a dual disc setup with the 4.5mm rotors. I have ridden my kz650 with the single and a dual setup, the dual drilled rotors stop a little more aggressively in usual street riding. Unless you are pushing your brakes to the limit repeatedly, I think the factory dual setup is mostly for looks. They look pretty good, and IMO that is a good enough reason to make the swap.

650ed wrote: Switching the forks around isn't a good idea because your fender stay mounts will be facing forward rather than toward the rear.

Also, be careful about which way the bleeder valves face. There is a left caliper and a right caliper - they are not the same. Ed

Put an ltd fender on there and forget all about that one that looks like it belongs on an old shwinn 3spd,then you don't have to worry about those fender stays! :laugh:
You can always have the rotors surfaced at a machine shop that does flywheels,For the calipers find a set off off a kz1000 ltd .

I did the conversion in 84 using H2 calipers. Yes the bleeder is in the wrong position on one. Not a problem. I bleed it with the banjo bolt. There is a adapter at OR I can use but it's not a problem. One day I'll get to it maybe. There's more important things top do.
Steve

You would also need to replace the M/C, because the M/C for a single disc is 14mm =1/2, & you need a 16MM =5/8, M/C for a dual disc set-up
Pete

Your right. The original M/C would work but a larger one is best.

I currently have a dual disk PMC master cylinder, 650D1 calipers, and EBC rotors made for a Z1R. The thinner disks on the 650D are also smaller so they dont work well. I used the 650 ones til I got the EBC rotors. I think any early KZ1000 dual disk model rotors will work. They are the correct diameter for the 650B/C forks.

I've bought a lot of different things to see what works. I think I've arrived at the best stock-ish setup with strictly bolt-on components.

I have a 650B2 front end that I'd like to fit with a second disc. From the research I've done it appears that all I need is an early model (77-79) KZ1000 rotor, (or second 650B2 rotor, both of which are 4-bolt, 296mm OD, 7mm thick) and the right-hand KZ1000 caliper along with it ..? From what I've read, I think everything should bolt right on. However, not sure if fork spacing, or hub width, on the 650B2 and 1000 are such that I'd have caliper/rotor alignment issues.. Looking for some input/thoughts from you all. Thanks!

Easy upgrade. All you'll need is a twin disc master cylinder, disc, caliper, bottom hose, dual splitter and a RH cable guide. You can have them in front or behind the forks your choice once you know which calipers you have a pair of.
Theres always a way to bleed them regardless of bleed nipple position. Bench, gravity, or reverse. One of them will work.
Twin disc master is a must if you want twin discs to be effective.

The caliper brackets are different! There is a left and a right bracket the bolts to fork leg. The caliper bodies are same and switchable. 650-750-900-1000 are all the same 76-80. And you need a 5/8" master cylinder for dual disc.