Commando "S" type part number

Hi All,

I had a blow out of the rear muffler mount washer on my high pies on the "S" on the bracket that comes down from near the seat.
Can anyone shed any light on the part number? While i have the feelers out, does anyone know where there is a part number supplement book for "S" models with part number for items only found on the "S" type???

Thanks in Advance!

Can't find the part number just now but RGM motors www.rgmmotors.co.uk does all the parts for S type exhausts, look in their online catalogue

On the 750S that I am building the two mufflers are tied together by a steel strap with two holes which is then bolted to the upper and lower muffler mountings by the standard rubber exhaust mounting 'bobbins' the other threaded end of the rubber mounts then go through the two corresponding holes on the mounting bracket that comes off the top left shock mount and they are attached by a couple of plain washers and spring washers or nyloc nuts. I recall reading a suggestion on this forum that a more solid stud arrangement with rubber buffer washers is a more reliable mount at this location, but I have no experience of this myself as my own bike is some way from completion yet.

i have had tabs welded to the frame to hold mounts which hold the mufflers/silencers.
i have the "L" bracket unused and the original styled heat shields also unused.
open to offers if you could use them
chris

I flattened and relieved the stock SS brackets to make a rigid mount between passenger footrests and the top shock mounts. This might be a superior mounting setup for the S models as well. I like the reinforced support between the shocks and Z plates enough to keep the brackets in place even though I have a low-level exhaust at the moment--when painted black they're very unobtrusive.


Tim Kraakevik
kraakevik@voyager.net
'72 Combat

The part number you are looking for is 06-1304. Called Silencer Bracket. It is available from several sources, like above mentioned and also Walridge I think. They are pricey. You can get the "S" part numbers from the "Commando Spares List, Supplements for 1969 and 1970" booklet if it is still available, there is no number on the book. Here is how the "S" pipes mount.



I also found this somewhere, so I can't credit the author and I haven't tried it but it sounds reasonable.

"I had a problem with my exhaust mount rubbers shearing after low mileage after I mounted a set of "S" pipes on my '70 Roadster. The original design of the rear mount looks too weak to me with just two rubber mounts holding both pipes. I worked up a new mounting system as follows: I used two stud-bolts (I used 2 Norton P/N 06-4688 studs (5/16x24) I had lying around) threaded one each into the mounting bosses on the two mufflers, then installed the flat bracket that holds the two mufflers together, then secured these brackets to the mufflers with backing nuts making a rigid assembly of the two mufflers. I then made a "sandwich" of rubber isolators over the two studs using a combination of Norton tank mounting rubber washers (06-0648) and drilled-out center rubbers from the original rubber mountings. Then fit the ends of the studs through the chrome "L" bracket with more rubber washers on the far side (need smaller OD washers here to fit inside the "U" shape - had to go search the hardware store to find some), then secured with flat washers and self-locking nuts.

This has worked well so far; the two stud bolts provide more strength for vertical shear forces from the weight of the mufflers. I have been careful not to tighten the lock-nuts too tight and not over- compress the rubber "sandwich" as the exhaust system needs some flexibility to vibrate with the engine independently of the frame.

This needs to be tight to keep the support, just not too tight. Hope this helps."

Dave
69S

Hey Thanks very much for the replies, the image makes describing the part number i need more clear.
Dave, part #06-1304 is the actual mounting bracket. I had the blow out of the threaded mouting screw that has the thick rubber washer that screws into the muffler. Is this part the same as any other commando muffler mounting set up?
Dave, i think i will have to run with your modification, it looks good!

I misunderstood you. The rubber gizmo is 06-0622, Fair Spares has them, as well as OldBritts and Walridge. They also fit the old head steady and the roadster mufflers.

Dave
69S