Need advice, my 1978 Kz1000 has the wrong shocks

Folks, I bought an incredibly poor-condition 1978 Kz1000D, it's the one they made back then that looked like a cafe racer, never saw any for sale until recently, but omigod its a mess.

Right now I'm just trying to stabilize the scene so I can get going on the re-do.
For starters, the bike was 'lowered' by 2 things: (1) the fork tubes were slid way up in the triple tree (now fixed); (2) tiny, short shocks were put on in the back -- they look so small they musta come from a Honda SL70. Chrome and tiny.

So here's my problem -- I don't know the right shock length for this bike and I want just the stock shock length.

Anyone know what the 1978 Kz1000 D's stock shock length was from the top eyelet to the bottom eyelet?


NOTE: In looking this bike up online, I'm led to believe that the shocks for the other Kz1000 models are not compatible -- according to what I found, this Kz1000 D model had shocks that were not shared with the other z1, kz900 or kz1000 models.

However I don't know that for sure.

Ive got a 1980 z1r that's on the project list also,anyway Its parked about 30miles from where Im sitting.
Im going to say the shocks on it are in the 12.5-13" range,they bolt up like any other kz shock they just don't have the cheesey looking chrome bodies/covers like the A-series bikes had.

ebay ads say 13 1/2 inches from eye to eye.

Good Fortune!

the shocks on this 78 look about right for origionals
[attachment:1]C:\fakepath\78.jpg[/attachment]

Well now the picture works!

Okay good deal, thanks all, now I know what I'm after -- so I looked ebay and found several examples but none of them have the change I see at the bottom of the coil spring on wireman's Z1r -- if you look at wireman's excellent photo there, the shock spring coils tighten up at the bottom.

All the examples on ebay do not have this change, this reduction in the gap between the adjacent coils, at the bottom -- the examples on ebay have gaps between successive coils that are the same the entire length of the shock spring, -or- the change in the gap is on top not bottom, maybe that's why the part number for the 1978 Z1r shocks is unique to that model.

Because otherwise there are several examples on ebay that otherwise look the same - black spring, no cap on top, black bottom, and chrome preload adjuster 'ladder.'

Take a look at the pictures in the link below. Style #2 in the first set of shocks looks very similar to the Z1R shocks. The blue and silver "HAGON" label peels off to reveal an alloy adjuster. I've had Hagons on my bike for a bit over 5 years and they still work like new. Ed

davequinnmotorcycles.com/cgi-bin/webc.cg...GON_TWIN_SHOCKS.html

650ed wrote: Take a look at the pictures in the link below. Style #2 in the first set of shocks looks very similar to the Z1R shocks. The blue and silver "HAGON" label peels off to reveal an alloy adjuster. I've had Hagons on my bike for a bit over 5 years and they still work like new. Ed

davequinnmotorcycles.com/cgi-bin/webc.cg...GON_TWIN_SHOCKS.html

Good deal, thanks there 650, looks like the one, looks nearly identical, style #2, not *too* pricey either. However they say "the fully compressed length is critical - you need to determine the clearance issues between back wheel and fender."

Yikes the rest of that page is complicated. Lots of degrees of freedom, lots of variables. They also want the uncompressed length.

Just to give you an idea of why, when I removed the 4-into-1 system that came with the bike, the asphalt had scraped huge holes in the bottom of the collector -- the tiny chrome shocks on the back are 10 3/4" in the uncompressed length, he musta been dancin with the devil ridin this beast with them shocks mein gott.

You might want to give Dave Quinn at that site a call. When I ordered mine I called him and he set them up based on my weight, riding style, etc. He might know what length shocks came on your model bike or how best to set them up based on his past experience. He's been selling these for quite a long time, so he's may have set up a few sets for the same model as yours. Ed

Z1R's had Mullholland (Or however there spelled) Rear Shocks. Same as LTD models. Black springs.
They have a small yellow decal name on the bottom chrome, at the adjuster.
They were a little more stiffer.

Anyone know what the 1978 Kz1000 D's stock shock length was from the top eyelet to the bottom eyelet?

I just measured one of mine. The free length (off the bike) is 13.5" center-to-center between the eyelets.

I'm led to believe that the shocks for the other Kz1000 models are not compatible -- according to what I found, this Kz1000 D model had shocks that were not shared with the other z1, kz900 or kz1000 models.

It's true that the '78 Z1R had unique shocks. However, it does't mean that the others are not compatible. I believe that shocks from any KZ1000, KZ900, or Z1 will work. The differences are styling and spring and damping rates. But all of the bikes are pretty close in weight, with similar frames geometry, so any of the other big KZ shocks should give you a decent ride.

if you look at wireman's excellent photo there, the shock spring coils tighten up at the bottom... ....maybe that's why the part number for the 1978 Z1r shocks is unique to that model.

I believe you are correct. The '78 Z1R shocks are the only model I have seen that used two separate stacked springs to give a progressing rate. I think even the '80 Z1R used a single spring.

The most similar will probably be the LTD shocks that are all black. I don't know if the Mulholland aftermarket pieces were the same as the stock LTD shocks, but I have a set of Mulhollands and they looks similar to the Z1R, but they have aluminum top caps on the springs (and a single spring).

Also, if you do go for the Hagon shocks, the graph in the factory manual suggests the stroke length is 80mm, or 3.15", which is close to the 3.2" listed for the Hagons.

The factory Z1R shocks had a spring rate of 1.8 kg/mm for the initial travel (about half way), rising to 3.0 kg/mm for the remaining travel. I believe this works out to 100 lbs/inch, rising to 168 lbs/inch.

I can post a picture of the spring rate graph from the manual if you'd like.