TOPIC:

Thanks for that but I'll be damned if I'm going to take the front end apart again just to satisfy swest's unreasonable love of rear mounted calipers

Unreasonable, love? I did it because that;s the way it's done. It's your bike, you can have it your way.
Steve

Come to think of it that seems like a lot of weight sitting forward of the centre line of the wheel. That combined with the rake of the forks might make for some interesting steering effects. I think I'll switch them around in the spring when I put the calipers on.

Stands to reason. Instead of pulling on the forks, they're behind them. Mine are H2 calipers I got when I was wrenching at a MC salvage yard.
I like them for the cooling fins and they take the same pucks as the Z1.
Steve

Keeping the mass of the calipers as close to the centerline of the steering stem is a good thing.

Hi I have a 76 and a 77 as all have said the 77 has the calipers in then rear I just put my extra 77 forks on the 76 .So now the caliper that was on the front left of the 76 is now mounted back right and I'll mount the second disk and caliper on the left side . I don't have the money to upgrade to better calipers ,but I think early Brembo calipers from a BMW would work without having to buy new disk's .The BMW's used thick disk's also .If you run steel braided lines these calipers work ok .Goodridge sells a double banjo bolt with a brake light switch so you could run 2 lines up to the master cylinder .www.amazon.com/Goodridge-Banjo-Built-In-...Switch/dp/B000GTV0RC
To change the subject ,if you have any trouble with your alternator rotor coming loose on a 76 with the first series charging system .You can lap the rotor to the shaft using valve grinding compound I did this over a year ago and solved my problem .Before you put miles on it you need to check your starter clutch bolts are locktited well.or you could trash your engine Also you can go to electronic ignition by using a 80's pick up plate and advancer ,and early 4 pole GM HEI module and a GM 4.3 V6 dual tower coil .This made a world a world of difference on how my bike runs . I dual plugged mine but haven't got 2 extra plugs hooked up yet.
Just PM me and I'll give you my number or email Paul N.

Thanks for that pass12me. Mostly I'm doing the dual disk thing for looks. I'm not doing any peg scraping and even the old single disk hauled me up pretty well.

I likely will PM you at some point as I try to put this thing back together since you seem to know a bit about these old twins

I went down a rabbit hole today working on my front brakes and if anyone can lead me out it's you guys.

Started when I pulled the piston out of the 79 KZ650 caliper I'm planning to use. It's pitted a bit so I went to eBay looking for a new one and got flummoxed. From what I could gather from Partzilla the 77-79 650's had 3 configurations, single rotor , dual solid rotors or dual drilled. Seems the ones with dual drilled rotors have a different piston and pads than the other two, dunno why. So, does it really matter regarding pads and pistons if I have drilled rotors as long as it all bolts together and the brake lever squeeses the rotor do I care?

Also, I want to get the calipers powder coated, should I also get the holder bolts powder coated or just clean them up (they look like stainless steel)?

Pics?
Steve

Pics you want, pics you get.

The left caliper (supposedly from a 79 650 (no sub-model specified). Stamped on it the following; "1 11/16" (!?), "U7" and "E". The right caliper (supposedly from a 78 650B). Stamped on it; "K4" and "B"







The left pads. Marked "TOYO C93FE 4318". The right pads marked "TOYO C93FE 3910".



The offending piston.

That's a nasty scar senior.
Steve

In the spirit of only trying to solve one problem at a time I'm going to try to rephrase my question.

I need a new piston for my left front caliper. Kawasaki made 2 very similar calipers seemingly dependent on whether the rotors are drilled or solid. That is to say, all the parts of the twocaliper variants are identical except the piston, the piston ring seal and the pads.

Measuring and inspecting my calipers I have 2 exact mirror images and the pistons are identical in height and diameter. So I have a matching set but which set? I suppose I could order one of each and send the odd one back. But I'd rather not.
Because the only difference between the two sets is pistons, piston rings and pads it stands to reason that one variant has a different diameter than the other. Presumably this has something to do with whether or not the rotors are drilled?

Anyone out there know the dimensions of 43048-1002 or 43020-1012?