Vincent Silencer

[deejay499]

I understand that the new silencers from the VOCSCo are as close to the original as possible. A lot of research went into making them. I am cerainly very pleased with the one that I got from them - sounds great with no loss of performance. Perhaps a bit more costly than other makes but well worth it.
DJ.

 

[John Emanuel]

As far as I know only the original Carbjector and the VOSC silencers have a true spiral baffle. There is, however, a vital difference between them. The spiral of the Carbjector is the full diameter of the outer tube, wereas the VOSC has the baffle welded within a perforated tube of only 2 1/4inches. This is flaired out at each end and welded to the inside of the silencer. The gas passage through the spiral is only around half of the cross sectional area of the exhaust pipe. Although there is an annular gap between the perforated tube and the outer. The gas presumably finds it difficult to pass through the perforations, down this gap and back through the perforations, resulting in the performance being seriously affected, not just at the top end but throughout the range. Also, it's not particularly quiet!

 

[Albervin]

In the 1923 Senior TT, Graham Walker used a Carbjector silencer on his Norton "with no noticeable drop in speed but a more pleasant note to the exhaust" He came 4th, missing 3rd by 1 second after 187 miles..

 

[VincenttwinPL1]

As far as I know only the original Carbjector and the VOSC silencers have a true spiral baffle. There is, however, a vital difference between them. The spiral of the Carbjector is the full diameter of the outer tube, wereas the VOSC has the baffle welded within a perforated tube of only 2 1/4inches. This is flaired out at each end and welded to the inside of the silencer. The gas passage through the spiral is only around half of the cross sectional area of the exhaust pipe. Although there is an annular gap between the perforated tube and the outer. The gas presumably finds it difficult to pass through the perforations, down this gap and back through the perforations, resulting in the performance being seriously affected, not just at the top end but throughout the range. Also, it's not particularly quiet![/QUOTE

Hi John, when I get around to taking the silencer apart I will give you the dimensions/info on the baffle etc. I may be able to repair my broken silencer as I think its just the tube the runs through the spiral baffle that has come detached. I have found this :http://www.brituro.com/page/products_and_services they list three silencers for the Vincent including one which states "carbjector baffle". I have tried to contact the "right guy" at this company for more info but so far no joy. Anyone have any info on this? Also new spiral baffle silencers are listed on Ebay from time to time, possibly made my this company??? Paul

 

[VincenttwinPL1]

Inside the Silencer!

Have a look at these photos:

From what John describes its seems the VOC Spares company supply a silencer constructed like my original.......

There should be 6 spirals. Spirals are 2.5" outside dia and made from .038" steel. Outside dia of the tube the runs through them is .5". Total length of the tube is 7.5" long. If anyone wants more details then let me know.....

The length of the perforated section welded between the silencer and the baffle is approx 11 inches. The holes are very small, approx .035"

Paul

 

[Tom Gaynor]

Modern "classic racer" practice would be to pack the body of the silencer with glass wool and insert a heavily perforated pipe (the OD of the exhaust pipe) right through it. If it worked the way it did on my Manx, it would actually increase performance compared with an open exhaust (megaphone), and drop the noise by 5 or 10 dB compared with "unsilenced". Personally I could probably accept a small drop in performance for a decrease in noise - I've heard some very quiet (relatively speaking) Vincents. But then I'd probably worry about increased timing case noise...so what I do instead is wear earplugs.

 

[VincenttwinPL1]

I agree with you Tom, unless your racing, a few mph at the top end and a second off the 0-60 time is of no interest to me. In my case I have got used to a Vincent that had its original silencer and that sounded very nice. The bike has been in our family for 40 years. When I broke the silencer and fitted a replacement that "very nice" exhaust note had gone! At some point I will repair the original and fit it back on the bike.
From my experience most "stock" motorcycles when new are fitted with quiet and restrictive silencers. That includes my modern bikes. The engine may last a bit longer and the neighbours don`t complain! The first thing I did with both my Ducati`s was to removed the stock silencers, not to gain performance but to get that lovely sound. My neighbour then told me his windows shake as I ride past but he had a smile on his face!! A modern Ducati with standard cans sounds all wrong, well it sounds wrong to me anyway, you can hardly hear it! But the v twin Ducati has a pipe and can for each cylinder so its sounds great when you fit race cans! Obviously the Vincent twin has the one silencer (unless its a lightning) and for me as soon as a performance silencer is fitted it just gets loud and barks!! Hey but we are all different!!!!!!

 

[Rixon]

Thread resurrection ! I have an old Vincent style silencer that came with my Norvin. Looking inside it has a spiral baffle arrangement.

Given that this silencer is at least twenty five years old, and possibly a lot older, does this mean it's likely to be an original one or were aftermarket spiral silencers available in those days ?

 

[vibrac]

I thought the spiral design was the original fitment? wasn't that why the club and the spares company jointly went to the expensive exercise of recreating them as the advert says read MPH 341 or is it already in the archives?

 

[stu spalding]

Some spiral baffle silencers were made by splitting large "penny" washers, twisting them, and tacking them together. Bloody awful! I had one and the tacks broke and all the washers stacked up in the end of the can. Plod reckoned it sounded like an anti-aircraft gun going down the street. Cheers, Stu.