Yep, reinstall in the same order they came out, that would definitely be disappointed to screw up. And my original assumption as to the purpose of the rings was correct -- yay!

I thought I was doing good because the washers I used fit easily into the swingarm, so I cut out the centers to fit over the piece of pipe and tacked them in place. That's when I discovered there's a lip inside the swingarm, past the bearing location, and the washers wouldn't fit past that point. Ah well, back on the lathe, and a quick pass with a file to take down the outer diameter and all is good now.

And apparently I should have turned down the juice on the mig by a notch. Made a bit of a hole in the outside of the washers when I tacked them. But again, oh well, it won't hurt anything. And once the bearings are in place nobody will see it again.

Looking at the parts you show I suspect the purpose those rings welded onto the tube is just to keep it somewhat centered in the swingarm so the swingarm bolt can find its way though it rather than hitting the edge of the tube. If those rings weren't there I think the tube would drop inside the swingarm when the bolt was removed. You did a nice job fixing it! Ed

After I finished the repair, I grabbed one of the old bearings to see exactly how the tube sits up against it... It doesn't. The tube is smaller and actually goes inside the bearing. For a moment my heart was pounding as I considered that perhaps the bearings actually sat against the outer rings, in which case the squareness and position of those rings would be absolutely critical! Ack!

Fortunately I realized the width of the pieces was all wrong, and after grabbing the sleeves and sliding everything together on the bolt, I could see what actually happens... The pipe sets the spacing of the sleeves, which then become the contact point on the inside of the frame. The combination of sleeves and this pipe create a slight gap inside the frame for the swingarm to pivot without binding on the frame. So I double-checked that no burrs had been created on the ends of the pipe during disassembly, but it all looks clean.



The new bearings are scheduled for delivery tomorrow. I'll get the tossed in the freezer overnight, and this weekend I can bake the swingarm in the oven for a bit to help set the new paint and have it nice and toasty for dropping in the bearings. Supposedly with the temperature difference they should only need a light tap to fall in place, and I believe the bearings just go flush with the outer edge of the swingarm. Hooray! The first pieces to be reassembled!

Harley-Davidson Sportster shocks are about the same length as the 750E's.
HD oem should be ~!3.5" or so, but there are also lowering & hugger shocks which range from 10-12" in length.
You'll have to swap bushings & the bottom eye is a tad too wide for the swing arm mount, so you'll either have to spread open the mount or grind down the eye 2-4mm.

I have a 1981 KZ1000J, and while trying to knock the bearings out of the swing-arm I seem to have mangled this center spacer (or maybe it was already like that, I never did find all the pieces)... Anyway it originally had a flat ring around each end which were destroyed. From what I can see, the only critical measurement appears to be the length of the tube, to prevent the bearings from working in towards the center. And I believe the flat rings were to keep the tube loosely centered when you slide the bolt through the swingarm?

So, is there anything critical about the size of those flat rings? I was thinking I could hit the hardware store for some washers of about the right size, and cut out the centers on the lathe so they would fit over the tube. A quick tack with the welder, and this pipe should be good as new? Or am I getting too hopeful here?

The paint is done on the swingarm and the new bearings shipped out today, so I just need to get this piece fixed up and I should be ready to put it back together again.

so sorry to hear of your wifes diagnosis copbike1000.

fwiw,
i run the 6 inch wide 190mm rear tire on my 1980 z1r 3/8's of an inch off center with absolutely no ill effects.
this allowed me to run a 3/8's offset countershaft sprocket and "not" modify my frame at all.

someone asked about if top level racers can tell the offset?

let me relate this story to you of a guy that was a mechanic for a superbike team.
he said that when his rider came in he glanced at the chain to make sure it was looking okay.and noticed that there was aluminum shavings piled on top of the swingarm slightly in front of the rear sprocket area.
upon closer inspection he noticed the rear wheel had become "cocked" over to the side enough that the sprocket was cutting into the swingarm.
he asked the rider how the bike was handling and the rider said "fine it seems like it is cutting out a little in the upper rpm range,
but beside for that it was fine" lol.

that's my .02 fwiw,

leon

Update!

New images
imgur.com/a/ov3PO

Modified ZX11 rim in unmodified ZN1300 swing arm. Stock ZN1300 axle used, zx11 rim uses same bearings. Rim is only offset from center by 4mm.

Need to cut into drive shaft housing a little for the rim, and possibly a little on the other side for tire clearance. Then add on some reinforcements to the swing arm.

precisely.
but,my thought would be to machine 32085 and 33032 as one piece that the bolts would then go through like arnolds.


then you would install the axle in the arm slide the spacers over each end,then install the whole assembly in the frame and then put the newly machined frame fittings in and tighten the bolts and your done.

arnolds off on a fishing trip and won't be checking back in for a bit,otherwise he would be here to tell us all about it :lol: .

leon

the 03/04 stuff is good to use you are gonna lose some ride height because the forks are a lil shorter and the 17" wheels.
but a carefully selected exhaust and some gullwing type upper triples can negate that .
the front end will need "tuned" for the weight .a call to a suspension house progressive/racetech etc.should sort out a set of springs to take care of that.
a stem swap will make it a bolt on.
machining tophats/spacers for the pivot should sort that.
weld some shock mounts on the arm and modify the brake caliper bracket to lean it back to clear the shocks and the rearend is sorted.

hth,

leon

I'll probably go with the forks, swingarm, and wheels from a ZX-6R. That seems like the most common front end swap. From what I've been able to find the 03-04 ZX-6R swingarm is 242mm wide at the pivot, which leaves 50mm to space things out.

With the ZX6R forks, do they need to be modified for the different weight of the bike?