Silencers for modded 99

Previously wrote:

My recently purchased 1962 slimline 99 has a twin front brake, downdraft inlet port head (possibly off a 650SS), rearsets, megaphone silencers, etc. Not much standard on it at all, really.

I'm trying to sort the bike out with normal footrests, standard seat, new silencers, etc.

Armours have sent me round silencers when I really wanted oval ones as on the 650SS, saying that some slimlines were fitted with round silencers. Is this correct?

On what model Dommi and what year were round silencers fitted?

Trevor Birkbeck

Hi Trevor,

You are correct in seeking the oval type of silencer but beware, Many silencers sold these days have a sealed rear end, ie. the inner pipes are welded to the outer rear end whilst the SS type silencer is open at the rear, and the inner pipe stops short by some inches and I believe that they had a baffle plate between the rear of the inner pipe and the rear of the body of the silencer. I've seen claims that the SS type silencers are better than the closed end types and there are manufacturers out there producing them, maybe someone else knows who, I believe that the round silencers were used for one year only, (around 1960),

Rob.

The tubular silencers were fitted to heavy and light twins up to 1962 and i would not discount them too quickly as the oval silencers are often dissapointing in the finish with thin casings and horrid seams along with a drooping tail look . Down pipes should have a small kick up below the gearbox and an even curve from the exhaust port (and they don't make them like this now).I would rechrome a set of orriginal pipes or get some made.

Trevor,

Are you planning to 'dispose' of thenon-standard bits? If so, can you let me know please?

Thanks

Robert's statement needs expanding or qualifying a little. The "tubular" or "peashooter" (according to at least one current supplier) silencers were only fitted FROM around 1961. The De Luxe big twins had them and so did the Navigator for a while. A general tip would be to use the oval type for any big twin or Navias they were even used on early Commandos. The round type seemed very short-lived.

The best oval ones have a rolled-in tail end. Armours have an untidy welded-up end - not like originals.

Cheers, Lionel

Have to dissagree Lionel, my 1960 99dl made in 1959 came with the Cheroot tube silencers, as did my 1960 88Dl. So your "current " supplier is talking cobblers. I was riding around this time. I also have a 60 road test and photos from the Ist owner. . I think that by 62 the oval type were standard but on this i am guessing. I can also confirm that the orriginal silencers had glass fibre sound absorbtion and were much better than the pattern ones.

Checking through my literature the tubular silencer was also fitted to Jubilles ,Electras ,standard and sports special Dominators, strangely all the pictures i have of 650 DL's show oval silencers,but i doubt that anyone is interested in that!.There is a photo in Bacons book of what appears to be a pre-production 60 DL Dommie with very odd tank badges,no tickler slot and the tubular silencers with the properly shaped downpipes that are not made anymore.

Hi Robert, yes they were fitted to Deluxe models as I said- "The De Luxe big twins had them". Hush my mouthfor getting the year wrong! (I DID say "from around 1961"!) Your 1959 was a 1960 model so I did have the wrong year. The round section was, as you say, only used until 1962 so the most common silencer was the oval type. My July 1959 '99'is a Bracebridge Street, widelinebike and of course had the oval silencers. These were also fitted to 1961 DL Navigators. I don't know about other years as mine is a 1961 model.

I worded the bit about the current supplier wrongly - it was intended for the term "peashooter"