Refitting swinging arm

[Stephen Foster]

Im at the stage of refitting the swinging arm & wonder if there is a technique ?
It is very tight entering the frame .
How do I fit it without scratching the paintwork ?

I havent fitted new bushes as they are perfect .

Regards,
Steve ...

[bsa-bill]

If you have some means of expanding the frame it helps, like a clamp that will work in reverse, doesn't need much.
otherwise  try entering one side and put a suitable punch in to keep it in place then with plenty wadding/padding around the frame lever with a pry bar against the frame and the outer case of the swinging arm to let it go in, don't think I explained that too well hope you get the drift (don't use a drift  )

[Goldy]

I would file a little bit off the ends to make it an easy fit, it all clamps together when you tighten the end nut.

[beezermacc]

I would be willing to sacrifice a bit of paint. The swinging arm has to be clamped very tightly to ensure the silentbloc bushes do their job so it needs to be metal-to-metal contact between the ends of the silentbloc bushes and the frame plates. Touch up the paintwork after fitting. I would be very reluctant to file the ends as doing this by hand is likely to leave the ends slightly out of square thereby compromising the grip of the bushes on the inside of the frame plates.

[Goldy]

All depends how good you are at filing.

[Jules]

Have I missed something when I've been reading about the fitment of the s/a bush - I note that it always refers to tightening firmly to nip the inner bush and stop it turning. my bike has a flange on one side with a bolt to actually lock the inner bush and stop it turning - did I miss something? am I unique with this arrangement??  *conf*cheers

[beezermacc]

I think the part you are referring to is actually the spindle, not the inner bush. The purpose of the spindle is to clamp all components together very tightly. The locating bolt is there to stop the spindle turning when you tighten it.
The swinging arm arrangement consists of the swinging arm (obviously!), a pair of silentbloc bushes pressed into the swinging arm (one from each end) then a spindle which passes through everything including the frame. I think the part you are referring to is the spindle which has an ear on one end so you can bolt it to the frame. The swinging arm pivots on the rubber within the silentbloc bushes. When you fit the swinging arm you are supposed to tighten the spindle tightly so that the centre tubes of the silentbloc bushes are a tight fit between the frame plates and the whole structure becomes semi-rigid so that the arm becomes fixed within the frame and moves and returns to a fixed position. Basically, it works like a rubber mounted wishbone on a car. If the arm rotated on the spindle the frame plates would wear and the whole thing would be very 'flappy' and unstable. It is quite common to find the arm swivelling on the spindle when the spindle hasn't been properly tightened. Hope this helps. I suggest you have a close look at the parts book.

[Jules]

thanks Beezermac, understand, cheers

[Sparky]

When it came to refitting the swing arm, I inserted a long threaded 3/8" rod through the other pair of holes in the plates the swingarm attaches to.  I used a pair of leather washers for padding against the plates, thick flat steel washers, and nuts threaded on the rod on the inner sides of the plates, and as the nuts were turned counterclockwise, it acted as a spreader to slightly widen the frame just enough to slip the swingarm in place with no harm to the paint.

[Sparky]

Correction; it was a 1/2" threaded rod...