bluezbike wrote: Yes the #s match to where it's safe to say motor and frame were made as a unit....this is an increasingly hard to come by bike and to many one of the coolest years. Please consider carefully what you are going to do with it. There are many things you can do for it to improve it's readability for today's world without sacrificing it's original looks. Replacing the old ball bearing steering setup with modern races, upgrading front shock springs and the rears can be done too, replacing rear swingarm bearings with needle rollers, good modern rubber, and if you find the double disc braking setup it's a good thing to do too.

Let us know what you decide....and more pictures please.

IMHO
bluesbike is NOT steering you wrong.
And this is from a guy who is sitting 25 feet away from my 74 Z1a that has everything on his list except the duel discs done to it already.

It looks great,
It sounds great with a pipe on it,
Light to light we don't have any problems with anything I care to take on (I do pick my racing carefully )
And it's still a 903 with the stock pistons and cams in him.

Oh, and by the way, It's like money in the bank.

Mike

Yes the #s match to where it's safe to say motor and frame were made as a unit....this is an increasingly hard to come by bike and to many one of the coolest years. Please consider carefully what you are going to do with it. There are many things you can do for it to improve it's readability for today's world without sacrificing it's original looks. Replacing the old ball bearing steering setup with modern races, upgrading front shock springs and the rears can be done too, replacing rear swingarm bearings with needle rollers, good modern rubber, and if you find the double disc braking setup it's a good thing to do too.

Let us know what you decide....and more pictures please.

thanks. The stock swing arm is what i measured. the guy that is building the hardtail says i will have 9.25 inches between the frame rails. that is not much diff than stock. I guess I will wait until the frame is done before worrying about the wheel and tire. Dont want to buy things twice.

ok WHEW!!!, Just went outside with flashlight in mouth and metric ruler in hand and confirmed my sprocket hole-centers.... My Wheels are Enkei, and the dimensions from Z1 are spot on.

torquey wrote: Though was still wondering if anyone knows what the #'s mean. I have seen rates for my bike range from 45/90 to 100/150

The key number for a spring is the rate. That is how much force (or weight) is required to compress the spring a certain distance. Generally this would be in pounds/inch, or kilograms/mm. So a 100 lbs/in spring would compress by 1" if you put 100 pounds on top of it, or 0.1" if you put 10 pounds on it. The larger the number, the more force is required to compress the spring, the stiffer the ride. So given the choices above, 45/90 would be on the soft side, and the 100/150 would be firm...

The fact that you give two numbers (45/90) suggests that the springs you were looking at are dual rate springs, or progressive rate springs. Basically, the spring rate increases as you compress the spring more. That is, the force required to compress the first inch is less than the force required to compress the final inch. To make this they generally have one section of the spring with a low rate, and once with a high rate, and you can often see that the two ends are not wound the same when you look at it. The idea is that the initial soft spring gives a cushy ride, but when things really get crazy and the wheel moves a lot it stiffens up the suspension.

The Z1-R came with dual rate springs. All they did was stack two different springs together, and put a plastic spacer between them to keep them in line.

There are a ton of other numbers too if you were actually ordering a random spring, like coil diameter, wire diameter, and how far you can compress it before the coils bind. But often when you're talking about a single application, all you care about are the rate (lbs/in) and the free length of the spring.

How you translate the bike weight, rider weight, riding style, and specific shock and swingarm geometry into an ideal spring rate is super complicated. At the very least it requires a bunch of trigonometry and fancy maths. But beyond that it requires experience to know how to translate "comfortable" or "sporty" or "twisty canyon" into a target number to put into the math. I can't help you with any of that.

Now i'm bothered because I JUST ordered a 630-530 conversion from Z1 and my bike is an LTD with 16" wheel....

Another option is to remove the bearing/sprocket mount from the wheel and have a new one made at a machine shop that will bolt on that wheel and fit the new sprocket.

Might cost $50-$100 or so.

Yea I initially thought the LTD sprocket would fit but nope, It has a 33t sprocket specialist sprocket on there now. Right now I'll stick with 630 for a while since I just went ahead and bought another chain since I needed the bike for school. Meanwhile I will be looking for an 18" police wheel so I can use the sprocket I bought and convert to 530 pitch then.

I really did blow out the shocks though now that I'm really looking at the pics.

bluezbike wrote: Your wheels look a lot like stock LTD's so it should be easy to get a rear sprocket to fit, any chance of just exchanging the sprocket you just bought instead of going through a wheel swap with all it's attendant headaches? Really like the colour of your bike BTW.

No way any KZ or any other Kawasaki rear sprocket will fit on that Morris Mag, I already tried. I contacted all the sprocket companies and ended up having Sprocket Specialist make me one. There is one custom wheel that uses the same sprocket, but I can't remember which one.

That's why I bought a set of KZ1000 mags to replace the Morris Mags, plus I wanted a cush drive. And someday I'll install them. :laugh:

Your wheels look a lot like stock LTD's so it should be easy to get a rear sprocket to fit, any chance of just exchanging the sprocket you just bought instead of going through a wheel swap with all it's attendant headaches? Really like the colour of your bike BTW.