Had a few nice days so I painted some of the carb parts and finished them up. I replaced all the fasteners with stainless steel.



I pulled the mechanical timing advance out and found it was seized. I was able to clean and lube it, so it works great now.



The swing arm came off to inspect the bearings. They are fine and have no play, so I cleaned and greased them.



I decided to ditch the secondary air system, so I pressed out the metal tubes in the plates, threaded the plates, and installed some 3/8 NPT aluminum plugs for a nice finish.

floivanus wrote: Shop I used to work for would weld anything in steel an inch or so for free. Guy I took my swingarm to (didnt wanna refill my gas) charged $35 to weld shock mounts on an alloy arm. And I have zero sandpaper in my house unless it is needed, OP says he is an apartment dweller so unless he is like my neighbors, and rents while doing a complete remodel it is slightly doubtfull he would.

And I purge tanks with argon while welding on them, after a thourough rinse and alcohol wash. There are shops too small to turn down any work that make their money $5 and $10 at a time.

I have heard of this. Purging the tank to make it safe to weld using a method like you mentioned to make it absolutely safe.

Ideally, I would like to remove all the tubes under the gas tank & take it to a welder but all tubes were tightly zip-tied on to their fittings and there are quite a few to deal with in that area. Maybe I'm making that part of the job out as being more difficult than it really is?

Anyway, thanks everyone fpr all the recommendations. I'm going to have to mull it over because I'm going out of town soon, or so I'm told.

Thanks Leon and Steve

I think my biggest issue will be tire/swing arm size. I'm pretty much held to stock ( 130/70 ) I believe. My GPZ has a 190/55x17 with 6" over, it works well. I agree with you, Leon, build it and ....... . Steve, I've thought about breakage too. Wonder why the gears would break ? I would think other things would break first, But it should be different.

don

I finally got my Police Rim on the bike, so I thought I'd document what I did finally, so it may assist someone else following the same route. Some of this may not apply to someone who already has a Kawasaki rear alloy rim, some of the problems I encountered may be because my bike was fitted with Lester Mags that were perhaps designed to fit all the other parts from the original wire rims. Someone going from wires to Kawasaki Mags would likely encounter the same problems I did.

I started out acquiring a 1988 18" Police rim. The first and obvious problem was the rear brake. Try as I might I could not find a rotor with the 7 bolt mount, that was the 295mm diameter of the stock rear brake. I had two front rotors from a GPz750 knocking around which would bolt to the rim. but were 260mm in diameter. I then began to search for a rear caliper that would work with a 260mm rotor and found that a GPz 550 used that size, so I thought I'd locate said caliper - more about that later.

Looking at fitting everything on the axle, initially looked straight forward, until the day I tried to put it all together. The Police rim and the stock sprocket carrier turned out to be incompatible, the boss on the wheel where the bearing sits is longer so the recess in the sprocket carrier is too shallow. Secondly the cush drive from the wire wheel doesn't fit properly, it's identical in every respect other than it doesn't have the little semicircular cut outs molded into it that fit around the same shape in the hub casting. There are also issues with the stock spacer on the brake side, the existing one is too big in diameter to go inside the bearing seal on that side. The stock spacer on the chain drive side is however the right diameter for the seal and the correct width for the wheel to be centered with the Police bike Sprocket carrier etc. Coming to the brake side it's then a matter of getting everything into the available space. With the stock Police spacer against the wheel bearing and the chain tensioner in place there is only about 20.5mm of space available for the caliper mount. A stock Police caliper mount is about 23.9 mm thick, if you plan to use the Police rotor and caliper. My GPz 550 was about 25.7 mm thick, I ended up getting this machined down by 5mm to give a perfect fit, but I also had to enlarge the bore of the mount to 20mm to fit the axle. I also had to enlarge the torque arm attachment point hole to 12mm to match the existing torque arm, with which it lined up perfectly when set up. The 5mm is removed from the outside of the caliper mount boss, if you see the original caliper mount, that will be obvious,

I've attached pictures, but to recap if buying a Police Wheel, get the whole set up, axle spindle, spacers and sprocket carrier, that way you will have all you need. Starting at the chain side of the swinging arm you will have the tension adjuster, then the stock round spacer which works with the Police sprocket carrier to center the wheel with regards to that side, there's a spacer in the sprocket carrier, I used the Police one here, although I think this is the same as the stock one. Then you have the wheel assembly and on the other side use the Police spacer that goes between the wheel bearing and the caliper mount, the stock one is too big in diameter to fit inside the seal. You then just have to modify the caliper to fit between there and the chain adjuster on the far side.

Here's the GPz550 caliper in place, I like the fact it's a lot more compact than the KZ1000a rear caliper, I also like the smaller diameter rotor combined with the 18" wheel giving a more open look.










I hope this will help someone else pursuing a similar modification, overall I like the Police rim, I could have done an easier conversion with a KZ650c rim that would have accepted my stock rotor and caliper, but I like the extra width of the 2,5" rim, i think that's a better width for a 120/90/18 tire and as already stated I find the 260mm rotor and the smaller GPz 550 caliper visually more attractive. It must also save some weight too. For my taste, the 18" wheel just looks so much nicer than the 16" it came with and while not stock it returns the bike to the look of the KZ1000A2 it was built as, rather than the LTD look the Lester mags with 16" rear had given it.

The finished article on my ride today.

just trying to get it running right with the GS swing-arm and PM brake.

I was planning my first move to be getting a stock carrier and sprocket and see if I can get the chain to clear the 150mm tire. I would downsize the tire if necessary to avoid offsetting sprockets or moving the tire over to the right. If what you heard is correct, I'll need to go down to at least 140mm. This might be best anyway if a 150 is too wide for safety like I have heard and davico might be implying - I have also heard this is fine, however.

Pictures would help. What are you trying to do? Restore to original or just get it running right?
In theory you could put anysize tyre on it,shove the whole lot over to the right and have it line up with the sprocket. Some people have no problem with running an off center wheel Apparently Harley does it (not a great recommendation) Some Japanese cruisers do it and what surprised me was that Kawasaki do it with the ZRX.
The GS swingarm is a common swap and you should be able to sort it. I think someone said to me that 140 is the biggest tyre you can get in it.
Other than that you could source an original swingarm ,sprocket carrier and brake caliper mount and put it back to the way it was. With and original size tyre. I think the 630 chain is OK. Again pictures would help.

What is the widest rear tire i can put on the stock '78 (B2) rim (16x3) and not have to move the sprocket in order for the chain to clear the tire?

I bought a '78 KZ1000 B2 that came with a botched GS swingarm swap that I need to fix. I know from reading several discussions here that I have several steps to go through before I get everything right but I thought I would start with this one question because it could help me understand my options in dealing with the rear tire width and simplify one part of the equation.

Here is what I am starting with:
GS1100 Swingarm that looks like it is from the early 80's. It is aluminum.
The GS axle. All of the KZ spacers plus a couple of washers.
A KZ mag 16x3 rim.
The wrong sprocket carrier - I think it is from a later model that is not as wide as the B2's
A sprocket that has had a smaller sprocket welded to it as a spacer
The rear and front sprockets are not aligned. The rear needs to be pushed outboard about the thickness of the rear sprocket plus 1/16th of an inch.
A 150 rear tire
A 630 chain
The chain rubs the tire
An aluminum caliper bracket made out of a single flat piece of plat aluminum.
A Performance Machine caliper
The caliper and bracket were not mounted perfectly and so rubs the disc with a noticeable drag when pushing the bike.

Thanks

jeffw wrote: Rides great and I am just finishing up a 1166cc build due to bad rings. I figured might as well go bigger if I am going to spend the money to refresh the cylinder anyways.

Sounds like a great plan Jeff :lol: By the way where did you end up hiding that battery over the swingarm ?

Thanks Scubaanders,

I paid $1000 CDN for it and dropped another $2000+ into it. I replaced all the wheel, steering head and swing arm bearings and seals. New chain, sprockets, starter clutch, air filters, braided lines, brake pads, handlebars, had the inside of the tank professionally rust proofed, installed an antigravity lithium battery (super small and light), and i did a rattle can paint job using, I think, Rustoleum engine enamel in Grabber Green. It turned out pretty good. The stripes I did with vinyl decal I bought of a local guy on Kijiji for $10 (4" x 10" roll in each colour).

Tyrell Corp wrote: They are pretty tight but nothing you can't manage by hand if you have the right sockets for both sides., no air tools required.

I had a problem with the needle bearings and insert bush stuck solid in a 550 project recently, even a 20 ton press wouldn't shift it. Several heating cycles with a blow lamp and a big hammer finally shifted it. Never seen one this bad before.

I got it off it was a 23mm socket I think.