finally.... success with swing arm / silentblocs on a 61 Super rocket

[mikeb]

I finally got my swingarm back together with new silentblocs and this afternoon had the pleasure of a rock-solid test ride. 

I started a couple of threads about this job and got heaps of helpful replies, and I made use of some really excellent old threads – if anyone comes across this make sure you read a lot about it and fully understand how the silent blocs work before diving in. Still, there were a few points that no-one mentioned so I’m writing some notes here that might benefit someone facing the same job.

• It was easy to get the swing arm out of the 61 superrocket with engine and gearbox in frame. Its was made easier by having the bike slightly raised (2" wooden blocks under the centre stand) so the swingarm can hang down for more movement. I also removed the right-side front footrest and the gearbox oil level screw - this helped make space to manoeuvre the swingarm back into place.
• Some people write that the two silent blocs have to be of equal length. What I found important is the combined length of the two new silentblocs is 0.5-1.0mm more than the distance between the two frame plates. Just hold them between the frameplates to check. One of my new silentblocs arrived a few mm longer than the other but I don't see a problem with this - just make sure they are both pressed in so the inner on each side extends evenly beyond the end of the swingarm - same on both sides and gentle contact in the centre.
• Others write about spreading the frame to get the new silentblocs/swingarm into place. You will need to do this if you do step 2 above. This made me anxious tho was quite easy - I used some threaded rod (with nuts, suitable large washers) through the frameplate holes above the spindle holes. It took only medium spanner force to create 1mm or more movement - enough  make it easy to get the swingarm in place. I did have to loosen the two mudguard mounting bolts (which attach to a bracket under the battery) to get that clear of the threaded rod.
• When I first examined the spindle hole I thought it was worn larger or oval by spindle movement as the spindle looked loose in the hole. I measured the hole and found only .005" ovality. The real problem turned out to be the old spindle had a metric thread (!!) and the threaded section was turned down from the 13/16" spindle. So the spindle movement in the hole was due to the narrower threaded section. ARRG. I made sure I bought a new spindle with an imperial thread - got a stainless one from CPC engineering in the UK - fitted perfectly (and looks beautiful) and the hole is again the right size. So DON’T buy a spindle with a metric thread! - there appear to be lots out there and many suppliers don't say so you better ask. or just buy a real one from CPC - great guys to deal with

HTH

[Worty]

Nice work mate.  I remember having to press mine in with a lot of vice pressure but, once started, they went in fairly evenly.  Problem I had was that the swing arm wouldn't go back into the frame, probably because the Silentblocs protruded slightly further than the originals even when fully pushed in.  Had to grind down the bushes slightly for a fit.  I then found the spindle wouldn't go through the bushes, so had to ream out the bushes until it went through smoothly.  Given the huge hassle I had with removing the old bushes, plus the fact it took me two days to just get the s/a on the frame, it was a miracle the whole lot didn't end up on the street via a closed window.

[RichardL]

Mike,

That's a good post which will surely be referenced by swingarm strugglers in the future.

Richard L.

[kiwipom]

hi guys, Wortluck says:(it was a miracle the whole lot didn't end up on the street via a closed window), yeah this kind of job on the A10 can be frustrating but `patience` is required to meet the challenge, well done Wortluck and Mikeb