TOPIC:

9am53 wrote:

well, if you are interested I just replaced the m/c from my 82 1000 (twin disk) and I don't know what to do with it...it was working fine I just didnt have room for it on my new bars. if it fits you can have it (my bike is an LTD so it may be kind of crooked...) I think using a double disk m/c would just give you more responsive braking...but I am not sure....anyways, let me know

Wow, thanks 9am53, I will consider it, thanks. You're right about the stopping power, I'm just a bit stubborn about finding the solution here to the stock m/c.

The other thing is, when I got disappointed today after looking around for a m/c rebuild kit, I decided "well the old guts don't look *too* bad" and I started reassembling the piston into the m/c and ......like the rabid idjit I sometimes am, I tore a hole in the rubber gasket on the left end of the m/c piston. If you look at my photo above of my disassembled guts, it's the rubber round part leaned up against the spring. Tore a hole right in it.

So that experience has me wondering "even if I can *find* a rebuild kit, just how easy is it to reassemble the piston/spring/rubber bits etc. back into the m/c"?

So I've got a hit now to my confidence in my ability to correctly re-assemble, and no rebuild kit. If I hadn't stopped drinking 6 years ago I'd throw back a couple just now.

Thanks 9am53, I'm going to pull back a bit from this and cool down and I may yet take you up on your offer, and thanks again.

Before buying new internal parts, would first assure m/c bore can be restored to serviceable condition. And that the bore isn't too badly pitted or otherwise damaged.

1978 KZ1000 continued the single front disk and introduced the trapezoidal m/c with the same 14mm bore as in the earlier barrel m/c design.

The 1979 KZ1000 introduced dual front disks and a larger 5/8" trapezoidal m/c bore.

The 14mm bore trapezoidal m/c is rare because it was used only the one year in 1978.
At least on the large fours. I don't know about whether it was used on other Kawasaki models or years.

MaKaw designed the 14mm bore m/c for single disk front brake and the 5/8" bore m/c for dual disk front brakes. Same applies to the barrel design.

Using a 5/8" m/c with a single disk will likely produce a less sensitive brake.

Using a 14mm m/c with dual disks may produce an overly sensitive front brake (including unintentional lock-up of the front wheel in emergency braking with resulting loss of control and bike tip-over).

The correct part number for the 14mm bore piston assembly is 43020-1002. Don't let the dealer tell you otherwise, as the parts microfishe for the 1978 KZ1000 may erroneously show the 5/8" piston assembly (which doesn't fit inside a 14mm bore).

Good Luck!

Might also check info provided at Redline Cycle.

Click here > Redline Cycle

Scroll down to 4th and 5th pics.

Excerpts from above link:


Kawasaki OEM rebuild parts for the 1978 KZ1000A models (single disc) with the trapezoid front master cylinder.....(not available as a kit).......Note: The retainer for these pistons is plastic and usually re-useable.....
Top: Piston & Seal Assembly..... $44.99

Bottom Left: Stopper...... $3.79

Bottom Right: Piston Boot...... $6.49

In Stock at Redline Cycle



The o-ring that sits under the plastic reservoir on these master cylinders often leaks due to age......This part is not and never was available from Kawasaki.....

We stock a high-quality replacement o-ring to fix this problem......Exact diameter and width needed, and resistant to expansion from brake fluid.....

No, you can't get one of these for 15 cents at Home Depot....... $3.50 each

In Stock at Redline Cycle



Redline site also says, "We often have rebuilt trapezoid masters for all single and dual-disc applications."

Good Luck!

Well, I just wrapped up about 4 hours of searching and calling around then found your post, Patton -- thanks.
Whew. I was starting to wonder there.
I cannot express how friggin relieved I am, and I want to thank you very much for that.

I need to clarify something with Redline and I'm going to call them tomorrow, but see for yourself -- pay attention to what the pistons look like. Here in order are:

1) the picture I took today after disassembling my master cylinder


2) a photo of the parts from Redline's kit for the '73-'77 bikes


3) a photo of the parts from Redline's kit for my bike, the '78 A2 model.


Redline's piston for the '73-'77 kit is an exact match of my piston. But Redline's '78 kz1000-A2 kit has a piston that is clearly chamfered on one end, while their '73-'77 piston is just like mine - not chamfered at that end.

Wonder if they got the photos mixed up on their web site?
What do you think?
p.s. the rubber squeegee on my piston slid down the pistion shaft in my photo, but it normally butts up next to the middle circular piece of metal just like Redline's '73-'77 rebuild kit.


I guess it's possible the prior owner of my bike did a rebuild on the mstr cylinder and couldn't find a '78 rebuild kit, same problem I was having, and maybe he just bought a '77 kit and used its piston. Wish he was still around so I could ask him!

Would defer to Redline's advice about what fits what, but am thinking the earlier 14mm barrel piston won't fit 14mm trapezoidal m/c.

Guessing the chamfer might result from an assembly line change. Also note the spring fitment onto the piston is slightly different in that I don't see an expected nylon swivel clip fitted onto a thin pin projecting from end of the piston, which nylon clip fits snugly into small end of the spring. I'm more familar with such nylon clip arrangement where the small end of the spring fts snugly onto the nylon clip to hold the spring in position onto end of the piston which allows the spring to freely rotate. But which is likely insignificant from an operational standpoint.

Your pic shows what appears to be the nylon clip still inside the spring and separated from the piston. Perhaps the thin pin projecting from end of the piston that the clip snapped onto and rotates around got broken off during struggle to remove the piston from inside the bore.

Might want to compare with dealer pricing on the piston, which was available three years ago from Kawasaki and might still be available. Ask specifically for part number 43020-1002.

And before purchasing new parts, remember to carefully inspect the bore for any damage that might prevent it from be restored to serviceable condition. Some minor pitting may be okay.

Good Luck!

"Last night I had a nightmare, I was driving my kz1000 down the road and squeezed the front brake and...nothing"



Is this a figure of speech"had a dream" or did you really dream and motorcycles were a part of that dream?


just curious ,because i have had motorcycle dreams and some related to crashing, one special dream which i remembered while riding the next morning and ,took corrective measures i believe was an insight against a certain stretch of road where i would pass cars on my way to a rural college most days at like 110....and after the dream of meeting oncoming traffic on this curve/stretch ,i stopped that move in that area for good......just curious......not a joke....thanks craig..



just curious.....thanks craig

trianglelaguna wrote:

"Last night I had a nightmare, I was driving my kz1000 down the road and squeezed the front brake and...nothing"



Is this a figure of speech"had a dream" or did you really dream and motorcycles were a part of that dream?


just curious ,because i have had motorcycle dreams and some related to crashing, one special dream which i remembered while riding the next morning and ,took corrective measures i believe was an insight against a certain stretch of road where i would pass cars on my way to a rural college most days at like 110....and after the dream of meeting oncoming traffic on this curve/stretch ,i stopped that move in that area for good......just curious......not a joke....thanks craig..



just curious.....thanks craig

No, I have an extra level of introspection I developed for stuff just like that. 'Auto suggestion' where you manifest what you think is well-known. Having a vivid dream is auto-suggestion sometimes unless you are self-aware enough to clean up your conscious thought about it.

A good analogy is the racing-driver maxim of 'Always look down the track in the direction you want to go, not at the wall your bike is *temporarily* sliding towards and you'll automatically take the right action to avoid the crash.'

Same as in everyday life. You just say to yourself "Ok, I *know* the wife's mad I just bought yet another vintage bike, but I don't want her mad, I want her happy" then you find yourself doing some righteous stuff like taking out the trash, fixing the dishwasher, washing her car, and so on. Presto the fear of her anger is mitigated.

You just can't let dreams or concerns or fears manifest into physical reality, and it's actually pretty easy to do it -- just take note of the concern and say to yourself "Yeah but I don't want that outcome" and you'll discover you're finding ways and doing things to avoid it.

[youtube][/youtube]