Silencers Commando 750

Most of them sold nowadays seem to be louder than the originals. I have some Norvil ones & they are definitely louder than the originals. Not unpleasantly loud, just louder.

I wouldn't think there are many Commandos nowadays that still have original silencers. Are you sure yours are original?

Ian

Tomas,

You didn't mention which 750 you are looking to buy silencers for. To the best of my knowledge the possibilities are:

• early Commandos with the "cigar" type silencers inherited from the Atlas/Dominator era
• the "peashooter" type subsequently fitted to most 750s, and
• the variant peashooter fitted to Roadsters.

Andover Norton six three different versions of the basic peashooter 06.1978, being combinations of the following possible differences:

• "sound reduced" vs. "sound deadening"
• seamless vs. seamed with Norton logo vs. seamed, no logo

Searching their site for "silencers" will bring up their entire range, plus assorted brackets and other fittings.

As for the difference between "sound reduced" and "sound deadening", and the relative merits of seamed vs. seamless, don't ask me, ask the very helpful AN support team.

I may be faced with the same choices later in the year, so do let us know how you get on.

Julian

I find current pattern peashooters available from a variety of suppliers too loud so when visiting autojumbles trawl for original Norton ones in reasonable condition - about the only place you'll find them today. Easy to tell the difference between originals and patterns by rapping your knuckles on them - originals have a solid sound and are heavier while patterns produce a tinny noise and are lighter.  

The other difference beyond the thickness of materials is the inner tube, current ones are just perforated tubes but earlier ones had a series of flutes pressed in form the OD to the ID facing the flow from the head which scooped air into the outer chamber. These flutes are much more efficient at reducing noise than a simple perforated tube which is not far off a straight through pipe.  

For my 1970 Commando Roadster, I had stainless steel, exhaust pipes and silencers constructed for me by Alldens. Richard Negus took the bike to them, and explained to them what he required. Richard informed me that the earlier Roadster silencers were better, and he supplied Alldens with drawings to fabricate them. There are or so I have been informed two versions of those Roadster silencers.

Andover have recently produced a version which has the correct flutes.

I purchased stainless steel "peashooter" silencers from Keihan in 2007. Unlike the silencers which I purchased in the 1980s and which rotted before my eyes, the Keihan silencers are still looking as new. I also used Keihan silencers on my BMW flat twins and these silencers also performed perfectly over many years and high mileage. Regarding the noise, I cannot recall how loud my commando was in the early 1980s but the keihan noise does not seem excessive although the exhaust note sounded louder to the rider after I had fitted Craven panniers. My silencers do not look quite as "silver" as chromed steel but providing you can live with that, then I cannot fault them