Atlas swing arm gaps

Hi . I am re fitting the swing arm on my atlas to the frame after replacing the dreaded worn bushes.
I have noticed that there is a fair gap between the arm and the frame. I didn't notice it when I removed it as it just dropped out. I've checked a parts manual and there aren't any spacers or end caps that would fill the gaps in.
Does anyone know the story on this?
Cheers mark

I've checked my Norton Service Manual ( a Norton Publication...not after market)....there is no mention of, nor shims shown, to close up the gap.

A look at my Atlas shows a gap between swingarm tube and rightside gusset plate of 0.110 inches. I cannot see primary side, but presume gap is similar.

From the assembly diagram, it appears the bushings extend beyond the swingarm tube, and would take up any end play. There is a center body labeled 'distance piece' on the assembly diagram that would control depth of seating the bushings.

Have you replaced bushings with NOS or equivalent parts? If there is no end play, and the swingarm tube is a press fit on the bushings, I do not think you have any problem.

Slick

That all makes sense Slick.
I have no centre piece so I'll place spacers on the outside. This will at least centre the swing arm hopefully on the frame.
I hope there's no off set in the design like my Commando. I spent ages figuring out why my commando weaved at high speed until we discovers the wheel had no built in off set.
Cheers Mate.

As far as I know, there is no offset as in a Cdo. Shim equally on both sides. I think you will be all right.

No center body? G15's used flanged bushings w/o a center body. Perhaps PO bodged it up. The G15 has an oil cup on the swing arm tube....do you? Were your old bushings flanged?

Slick

there should be clearance on each side, its the inner bushings of the isolastic bushings that come in contact with the frame plates and are prevented from moving by the tightening of the 1/2" spindle.

hi hillbone,the distance piece between the two silent bloc bushes is essential,asuming its a std atlas swingarm and bushes chris

Morning lads. The old bushes were lost by the dude that pressed them out. I,ve just spaced them out equally and left a few thou so the arm won,t bind. Looks all good at this stage.
Another topic. I'm surprised that sourcing mono blocs is a bit of an issue. I know I can buy new, but at $450 each, that's a fair whack. The concentric just doesn't look right. Its a 1966 so it should still be a mono bloc.
Cheers again and thanks for your help.
Mark

chris plant said:

hi hillbone,the distance piece between the two silent bloc bushes is essential,asuming its a std atlas swingarm and bushes chris

Click to expand...

Pay attention to Chris!

The inner steel sleeves in the Silentbloc bearings must be held apart by a steel spacer, so they are clamped up by the spindle and the frame plates and do not turn with the swing arm.

Agreed - if you are refitting the original (silent bloc) type you must have the distance piece between the two bushings.

Andover Norton do a kit which is available all over the place (including eBay)



It is the distance piece that allows you to torque up the bolts without deforming the gusset plates on the frame.