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Brituro silencer

Submitted by dan_field on Thu, 25/08/2016
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Light Twins

I've just bought a pair of silencers from the club ( brituro cigar type) does anyone know what the thread is in the captive mounting nuts, I kind of expected that it would come with 4 bolts but it didn't!

Dan

Submitted by patrick_mullen on Fri, 26/08/2016

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Hello Dan,

I'm afraid that I am not much help as my Jubilee silencers which came from Armours have M8 threads- and the silencers on the Navigator which also came from Armours (at different times) have 5/16 UNF threads. The peashooters (which did not come from Armous) on the Yamton have 5/16 UNF.

I expect that the correct original Norton silencers fitted to Dominators/Lightweights were probably BSF or Cycle thread.

You raised a query about the rear brake pedal. I don't know if there are differences between early or late models brake pedals but I do know that the silencer mounting brackets differ. The change was somewhere about 1963 and it was a change to the amount of offset.

Patrick

Submitted by dan_field on Fri, 26/08/2016

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Thanks Patrick, I thought as much! I've tried metric and BSF, I think I tried BSC but couldn't find my thread measure to be sure, if it was then I guess it can only beUNF/C! Its too fine for Whitworth.

I'll try again this evening. I think I've overcome the brake pedal issue, there was lots of sideward play so I was able to put a washer between the pedal and the frame which has, I think just about given enough clearance. I've made some hangers from flat bar with the intention of just keeping the pipe out of the way of the rear brake arm. In due course I'll be experimenting with a 2 into 1 pipe!

Submitted by dan_field on Fri, 26/08/2016

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After a lot of fiddling and cleaning threads I found they were UNF, but am still fiddling with washers to get every thing clearing ok!

Submitted by richard_evans on Fri, 02/09/2016

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I've just fabricated new hangers from 20x4mm stainless strip and tried to get the offset reasonably right and then fine tuned with washers. It's quite a job getting the clearances right, particularly on the foot brake side and it needs quite a bit of care to ensure that the kickstart does not come into contact.

They look very neat and probably over engineered.

The four bolt threads into my silencers, not the same make as yours, but bought about twenty years ago are 5/16 BSF

 


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