The Everlasting Lozenge.

[lathejack]

The B50 Victor I bought last December was fitted with a hideous short stubby 'silencer' that would be incapable of providing any silencing effect whatsoever, I detest excessively loud road bikes.
The best silencer I have ever seen for the B50 & B25 is the standard Lozenge, a beautiful example of factory fitted functional bling, in my opinion at least.

A genuine NOS Lozenge I saw some months ago was priced at almost £600, shan't bother with that one then. So that leaves the newly made ones from Burton Bike Bits, when they have them, or the occasional used ones that are still sometimes expensive or corroded, sometimes both.

So I thought I would have a go at making one myself, they are not the easiest shape to reproduce with their radiused corners and gentle curves in all directions. So to prevent all my efforts rotting away I chose to use Stainless Steel.
But one Lozenge is never enough, so while I was at it I thought I would make a second one as a spare for my B25 Victor.

Silence is not Golden, it's Stainless.

And then I thought why not manufacture several more while I am in the mood.
So here is a small batch in progress, together with pressed blanks awaiting cutting and forming into the initial distinctive shape.

It's early days yet, with much work to do. The internals will follow a similar pattern to the originals, which someone kindly revealed when they cut theirs open and posted pictures on this Forum a while ago.

Although they are being made from Stainless Steel they won't be polished, there is enough work and cost involved in them without creating more toil. So they will be bead blasted and painted in heat resistant black, hopefully just like the gorgeous originals.

[midgie]

Nice work Gene.

[minetymenace]

Ge nice to see some piccies of the process as well as the evolving bits....

[beat]

[lathejack]

I have only been able to work on the batch of lozenge silencers very briefly in the last several weeks, but I have made a little more progress over the last couple of days.

I loosely assembled the B50 cases, barrel, head and exhaust pipe into the frame, and popped on an old rear mudguard.
After a lot more shaping, cutting, trimming, bending and twisting of a few of the silencer shells I was finally able to offer one up to the bike.

The mudguard was fitted to ensure there was sufficient clearance between it and the back of the silencer. The cutouts to clear the shock absorber needed careful attention to get them in the correct place and with enough clearance. The original on my B25 Victor almost touches the shock spring at one point, and cannot be adjusted further away.

I am unsure whether to make some silencers specifically for the B25 and B50, or just make them all to suit the B50's larger diameter exhaust pipe, with a reducing sleeve included to allow them to fit the B25.
There are no innards made or fitted yet, that's the next job. The tailpipe will probably be set at a slight angle to direct gases away from the rear indicator, which I think was done on later B50 silencers.

Lots more to do, including making all those heat shield mounting bosses.

[midgie]

Nice work Gene, I would say you could sell all you can make. you are correct about the outlet turn on the 72 model types. keep it up!

[lathejack]

Thanks Midgie. I have just read the thread on your fabulous restored B50T, and your photo of the rear end is handy as it shows the tailpipe angle. This is the only photo I have ever found showing the tailpipe detail on the later losenge silencer.

I am not a fan of working with Stainless Steel, I also have to fabricate with it at work from time to time. But my interest and enthusiasm for these fascinating bikes makes it worth the effort. Plus with all the cost, work and effort involved I think making them rot free is worthwhile.

[midgie]

Hello gene glad the shot helped you, bsa must have worked out that there was a corrosion problem with these as the later ones were also galvanised under the matt black paint.

[lathejack]

Well that's a surprise, I never knew BSA had taken the trouble to galvanise the later Lozenge silencer. Was it just the outside surface that was galvanised?

I have been working on the internals, and have one Lozenge almost completed. The internals follow a similar pattern to the originals.

image.jpg[/attachment [attachment=2]image.jpg

[midgie]

Looks a cracking job Gene. yes only the outer was galvanised on the later type.

[Johnq1]

Fabulous job Gene, I've got a mate laser cutting heat shields for mine I will let you know how they turn out

[JB]

Excellent work Gene, very much interested in one for my B25T at some point.

[lathejack]

I have machined up and welded on the heat shield mounting bosses. With the heat shields fitted it is now looking a bit more like the finished article. The small top heat shield is one I made from stainless.
The tailpipe is tacked in place, angled to miss the rear indicator.

[beat]

[skippy]

It looks really good. It's the first time i have seen what is inside one.

[Malcolms Lad]

This looks incredible, great to see such attention to detail. Great work mate!

[Canberra]

So much work to make the bike quiet and they still had to resort to the dual silencers in 73. Did they pack the silencer with anything else or just air? Marvellous job Gene.

[lathejack]

Thanks for all the encouraging comments.

The photo of the cut open genuine BSA Lozenge, showing its rusty internals, was originally provided by Anders Palm and posted by Roadplough in the Tech Write-Ups section of the Forum, just over ten years ago, so it's thanks to them for showing what's inside the Lozenge.
Anders also provided info on the internal diameters of all the tubing inside the original Lozenge. All valuable information which allowed me to go ahead and make close copies of the original.
His photos didn't show any sort of packing inside, so I assume there wasn't any. There are five chambers inside the original Lozenge, the two near the top, and the one at the bottom certainly don't have packing. The middle two chambers have so much room taken up by the cutout around the shock absorber that I'm sure there is no packing there either.
Anders did put packing into his modified internals though.

The internal diameter of the Stainless tubing available that I have used is a little larger than that on the originals, which can't do any harm.

[lathejack]

At last, I finally have one Lozenge silencer completed and ready to fit. I just need the B50 finishing so I can fit it.
I must now find the time to work on and finish the rest of the batch of silencers, there will be lots of late nights and into the early hours of the morning spent in the workshop to get them done.

The completed and fully welded Lozenge was first treated with a pickling paste to restore the surface, then bead blasted before being given a coat of heat resistant black paint.
New Stainless Steel securing screws for the heat shields were sourced, these are M6 thread but have the same looking head as the originals.

[minetymenace]

'king fantastic

[Ian Hingley]

'ckin amazing!

[b50whisperer]

same from me...absolutely amazing

[AJ CCM]

same from me...absolutely amazing

And from me Amazing, you won't have any problem selling them that's for sure.
Proper British Made

[lathejack]

At the risk of boring everybody with yet more photos,
I checked the fit and appearance of the finished Lozenge on the B50.

I then made a reducing sleeve and fitted the Lozenge to my B25T Victor. The new Stainless silencer has the same radiused edges and corners as the original, but it does not have the long bend in the side from end to end. Instead it has a bend at the point of the cutaway around the shock absorber.
It still fits and tucks in the same as the original, and seems to look just about the same as the genuine article.

I then started it up and went for a ride round the local country roads. It sounds just about the same as the original Lozenge did when it was in sound condition, with the same sort of hollow, tinny sound at low revs, which I quite like. Open it up though, and it still sounds a bit like thunder.

My Victor 250 has a low mileage, yet the original Lozenge silencer is already beginning to corode away inside a little, with some holes appearing through, resulting in a sooted up shock absorber and a harsher exhaust note.
So I now have a new Lozenge, which was just about an almost unobtainable item, and a major missing part on my B50T. Plus I won't have to worry about it rotting away.

[midgie]

Good work Gene. now get back to work and make some more!

[JB]

Very impressive work Gene & all in stainless, what's there not to like

[P.G.50.S.S.]

Hello Gene my name is Peter and I have just found your posts about the Everlasting Lozenge and thought it was GREAT , I am having a lot of trouble with mine on my 1971 B50ss it has only done 5800 ish miles and its been repaired 3 times!! Now for the big question, are you making any more? and if you are can I buy one, hope you don't find this to cheeky ?

[minetymenace]

to the forum P.G.50.SS

[JerryT]

Would certainly be interested myself if these were available to buy - Gene??

[BasilF]

Or if you don't fancy making any more could you post a tutorial on the panel beating stages to get the lozenge shape? I'm desperate enough to try and make one as the two I had to fit to my B50 have turned out to be rusty wrecks and Burton bike bits don't have any new ones.

Basil