As Gilda used to say "Its always something!"

Guys, there are several ways to skin this cat. I like to measure first: add bushing flange thickness to swingarm pivot width and compare to sleeve length; a 12" caliper is a good thing to have on hand. If the sleeve is short, it's easy to take material off the swingarm before installing the bushings; the steel is soft and the holes are chamfered, so a few strokes with a flat file will do the job. If you freeze the bushings and clean and heat the swingarm holes, the bushings will usually go in with thumb pressure and a light tap or two with hammer and wood block for final seating. There's no need to use a lot of force.
 
I like that. 1 mm matters in the context of the pivot but matters not in the context of removing 1/2 mm from each end of the swingarm with a file.
 
I have been agonizing over the fact that my sleeve is shorter than the brass bushing flanges. In typical male fashion, the LAST place I will check is the shop manual where it clearly shows shims for the end of the sleeve to make it slightly longer than the bushings with a sub note "do not loose!" Too late for me. If I ever had some they are long gone. I found some at a place called yammabits.com in the U.K. they are .0039" so you just order what u need. Does anyone have any experience with them? All the prices are in odd ball money so I can't tell what anything costs.
 
Doug79 said:
I have been agonizing over the fact that my sleeve is shorter than the brass bushing flanges. In typical male fashion, the LAST place I will check is the shop manual where it clearly shows shims for the end of the sleeve to make it slightly longer than the bushings with a sub note "do not loose!" Too late for me. If I ever had some they are long gone. I found some at a place called yammabits.com in the U.K. they are .0039" so you just order what u need. Does anyone have any experience with them? All the prices are in odd ball money so I can't tell what anything costs.
Click to expand...

Hi Doug,
still got the old sleeve? And a hacksaw? Or better yet, a Bro with lathe? Your new free shim is just a slice away.
 
Those shims aren't used to make the sleeve longer, they fit over it and, in effect, make the swingarm/bushing assembly longer. They were used in the cases where the sleeve was too long.
 
It looks like I am going to stay with plan A and spot face a few thousands off of each bushing and then shim between the end seal caps and the frame. From a dry fit, it looks like about .025 on each side should center the swing arm without binding it.
 
A small amount of space between the arm and frame is normal. Tightening the pivot bolt will pull the frame in and take care of that. You wouldn't want to see a large amount like 1/4" or something, but I think what you've got should be fine.
 
When I got my 81, I thought the bushings were bad because the rear wheel swung sideways a lot. Scary to ride. I got the guy to knock back the price.
When I got it home and went to remove the pivot bolt, I found the threaded part had broke off and the po drilled and threaded the end of the pivot bolt for a 5/16 bolt. LOL
I tore out the swing arm, cleaned the old crud out, and every thing looked pretty good. The pivot tube was a snug slip fit in the bushings. Not much of any apparent wear. I put the swing arm back in with a spare pivot bolt. With the pivot bolt at around 45 ft/lbs. it would still wiggle a bit left to right. Pick up the swing arm and it fell down. I increased the torque a bit. Around 50ft/lbs. picked up the swing arm and it dropped slower. Added a bit more torque till it would hold it self up. I could move it easily. This was around 55 ft/lbs. this eliminated any side to side play.
With some grease it works just fine.
Because of this I now believe that before I replace anything on a swing arm I shall tear it down, clean and inspect. Then test as I did on the 81. The bushings may be ok, just a loose pivot bolt.
With the loose pivot bolt the pivot tube is not held in place by the clamping force of the bolt. This allows the swing arm to move left to right even with good bushings.
So I would recommend at least torqueing the pivot bolt before you decide the bushings are bad.
If even with some extra torque the swing arm still has excess side to side play, then replace the bushings.
Leo
 
So I ordered new bushings from 650Central. The ones I got from MikesXS were so tight they bent the fender washer on the all thread. Crazy tight. Received the the bushings from 650 Central today and they are tight, but easily pressed in with all thread and a washer. Night and day.
I also took a bit off of either side of the arm with a flat file (per Grizld's advice)
Everything seems to be ready for assemble and I'll do it tomorrow when the bushings are frozen.
 
Gee, Leo, that sure looks like a better procedure than measuring components so you know what the free play is going to be--just crank down on the pivot bolt, much faster to do! BTW, the swingarm should fall under its own weight at spec torque.
 
Finally got a chance to work on the swing arm this morning. put a good quality caliper on the parts and found the swing arm sleeve was a full .010" narrower than the bushings. Amazing! We Screwed around on he mill for about a half an hour and found the swing arm is very hard to set up accurately so we ended up at the good old H.F. vertical disc sander and took material off until we liked the looks. Im going to assemble the thing, as soon as the garage gets warm enough to stand it. torque the pivot bolt to 45 ft/lbs and measure the side play. then shim between the end cover seals and the frame to get a good tight fit. I would sure recommend that anyone making this conversion to stack up all your clearances prior to installing the bushings. It would have been very easy to chuck the bushings in the lathe and remove the exact amount needed.
 
I recently found what I consider to be a better torque value listing, in the '77 and older manuals. I think it's better because they are all given as a range instead of just one single value like the newer manuals. The newer manual tells you one number for the swingarm pivot bolt, 47 ft/lbs. The older manuals give a nice range, 36 to 58 ft/lbs. This will give you some "wiggle room" (no pun intended, lol) to play with the tightness and achieve the proper "gentle drop" fit. As long as you can do that and still remain in the given range, you should be good to go.
 
I installed mine with the 47 ft/lbs and it took all of the side clearance out and the pivot sleeve appears to be clamped in place. Sure wish there was a way to verify that. got to go get a couple of 6mmX1.0 zerks so I can put some grease in the bushings. Then I will Locktite the nut and get on with my life, This swing arm has already taken way more time than it deserves.
 
One new fitting in the center of the arm works best. Just up onto the gusset plate insures enough material thickness so the fitting doesn't stick into the arm and possibly hit the sleeve. Your new bushings are designed to receive their grease supply from the rear (or bottom). They have swirled grease grooves running top to bottom. The original plastic bushings were designed to get their grease supply from the side and that's how the original grease fittings deliver it.

SwingarmGreaseNipple2.jpg


You can mod the sleeve to make it deliver some grease to the rear of your new bushings using the stock grease fittings. Drill a couple more holes around the center (red arrows) .....

PivotTube.jpg
 
Has anyone else had trouble getting the brass swing arm bushings to take grease? My gun pumped what seemed like enough to fill the shaft but then locks up. I loosened the shaft nut but that didn't seem to help. Shit! I just realized there has to be holes in the sleeve which i'll bet you have to line up with the shaft holes or you will have to force grease around the bolt to get it thru the sleeve hole and into the bushing. It's coming back apart for about the !0th time.
 
Like I said, the original greasing arrangement doesn't work well for the new brass bushings. They need their grease supply delivered from the rear not the side. The only possible way is if the original holes in the pivot tube happen to fall on one of the swirled grease grooves in the new bushing, but the chances of that are hit and miss. You need to mod the sleeve (drill extra holes in the center) or add another fitting to the center of the arm. I do both. Even though the original fittings won't deliver much grease to your new bushings, you still want to give them a shot of grease occasionally. That will keep grease between the bolt and sleeve. When mounted, these two parts don't move in relation to one another. They will rust together and seize up eventually.
 

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