Installing Swingarm Spindle

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I have renewed the bushes and the swingarm spindle in my 1973 750 Commando. The new spindle was any easy slide into the new bushes prior to fitting the bushes in the swingarm. Now with the bushes fitted the spindle does not want to slide into the bushes. I am reluctant to use too much force. Is there a trick to getting the spindle into the swingarm once the bushes are fitted? Would placing the spindle in the freezer overnight help?

Thanks

Bazz

1970 Bonneville
1973 750 Commando
1993 Harley Dyna Wide Glide
 
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Bazz I had to run the reamer through both of my new bush sets I fitted. 3/4" I think. Im in Wollongong if you get stuck but any engineering shop would be able to do it for you.
Ian
 
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I had the same problem with new bushes, had to run a ream through bushes.
Fitted Heinz Kegler's swingarm rings as added insurance to keep spindle firm against forward cradle.
 
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There's a long thread on this subject elsewhere on the board, started by moi.

Long story short, the good advice I got was to use a little valve grinding compound on the spindle, work it into the bushes and rotate to wear down the bushes a bit. It takes a while but it works. Then be sure to clean those bushes THOROUGHLY.

Worked a treat, and no special tools needed.
 
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Make sure to use the grinding paste with the old spindle, there is no point wearing out the new one before you fit it and as Brian says clean very thoroughly indeed afterwards..
 
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Bazz said:
I have renewed the bushes and the swingarm spindle in my 1973 750 Commando. The new spindle was any easy slide into the new bushes prior to fitting the bushes in the swingarm. Now with the bushes fitted the spindle does not want to slide into the bushes. I am reluctant to use too much force. Is there a trick to getting the spindle into the swingarm once the bushes are fitted? Would placing the spindle in the freezer overnight help?

Thanks

Bazz

1970 Bonneville
1973 750 Commando
1993 Harley Dyna Wide Glide
Bazz,
The interference fit of the bushing in the swingarm is designed in. They call it 'crush'.It's necessary to get them to stay put in the swingarm and it's taken into account for the final fit on the spindle. Sometimes they don't get it just right, ahem.. It might be easier to leave the finish on the inside of the bushing alone and take the outside down a little.
What I did was install the bushing, found the spindle didn't fit. Took the bushing out, cleaned the outside of the bushing and inside of the swingarm really well with emorycloth. Pressed the thing back in with a threaded rod, (3/8" fine rod costs $5 and works great because you can use 3/8" sockets to press things in and out without hammers.) Presto, it worked.
 
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Please don't use valve grinding paste on a porous bush ,it will get imbeded in the pores and you will never get it all out.
 
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Thank you all for the advice. Reaming sounds like the best way to go so I have taken the swingarm and spindle to a local machine shop who will do the job. I have also drilled and tapped exra threaded holes at each end of the spindle tube into the spindle to take 1/4 inch bolts. Hopefully this will give extra support to the spindle.

Cheers

Bazz
 
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Baz, I don't think the wall thickness of the tube is enough to support mounting bolts on it without welding nuts on to the tube.
 

Flo

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Could I ask where these bushes came from, as I have never had a problem with them. Or have I just been lucky?
 
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Flo, I've found this tightness with every bush I have ever fitted, I think these and most other bushes on Nortons were designed to be fitted and then hand reamed to size, very labour intensive and not what we have become used to with modern equipment.
 
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My replacement bushes were tight also. Not sure of exact source as they came with the bike, but they had an official Norton part number on the bag.
 
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dave M said:
Baz, I don't think the wall thickness of the tube is enough to support mounting bolts on it without welding nuts on to the tube.
Baz, I don't think the wall thickness of the tube is enough to support mounting bolts on it without welding nuts on to the tube.

Agree the wall is thin and only allows a few threads to be made. However, I have tapped through the spindle so I figure with the 1/4 bolt tightened up against the spindle tube it should hold the spindle in place. Effectively what I have done is replicate the existing centre fastener. I guess if it doesn't work I can always install the Kegler collar setup in the existing holes that I have tapped.

Flo said:
Could I ask where these bushes came from, as I have never had a problem with them. Or have I just been lucky?
[/quote][/quote]
Bought them from my local Brit parts supplier in Sydney. Don't have the package that the bushes came in. The new spindle package is marked " Firebird Brand Distributed by MCA (Aston) Guaranteed made in England"


cheers

Bazz
 
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MCA procure pattern parts so that may explain the tightness, a sample of one tells you nothing of course.
 
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Bazz said:
Agree the wall is thin and only allows a few threads to be made. However, I have tapped through the spindle so I figure with the 1/4 bolt tightened up against the spindle tube it should hold the spindle in place. Effectively what I have done is replicate the existing centre fastener. I guess if it doesn't work I can always install the Kegler collar setup in the existing holes that I have tapped.
I think when the spindle tube in the cradle was put in it was designed to hold the oil and not much else. I think it's true that the plates bear all the stress from the spindle it's the stretching of the holes that is the cause of a loose spindle. Welding nuts to that tube or clamping onto it just won't get you much. In a fit of overkill, I cut it out, made a one piece tube and had it welded to the cradle. It spreads the load over a larger area of the plates. Slightly less overkill would be to have bead laid down around the tube along the plates. Any weldor will tell you that laying beads will shrink things and it will shrink plates around the holes.
Installing Swingarm Spindle


Are the spindle bushes sintered? I can't remember. Even with an ultrasonic cleaner, I wouldn't feel too confident about getting it completely clean if you use lapping compound, in any case. You might want to ask the machinist to mount the bushes on a mandrel and turn them down a little on the outside, or even just dress them down with an abrasive strip. It's probably going to be around a thou. There's no need to find out if you happened to get a really talented machinist, who happens to be having a good day; when you have him line ream the bushings. It's a really hard thing to do, and you'll never get the finish you had originally. In my dotage, I'd be inclined to send the bushed back, get a Green Globe set and see if they fit.
 
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bpatton said:
Bazz said:
It's a really hard thing to do, and you'll never get the finish you had originally. In my dotage, I'd be inclined to send the bushed back, get a Green Globe set and see if they fit.

That is as risky as any of the other options.
 
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Got the swingarm with bushes installed back from machine shop. Did a nice job reaming the bushes, cost $20.00 Aussie. Everything went back together and now have nice swingarm movement with no side play.
Can't wait to ride the old girl again.

Cheers
Bazz
 
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Most bushings I've seen, much more truck and bus stuff than bike, are pressed in and then reamed to size.
 
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