Is this is Triumph 5/1?

[VintageBike]

Can anyone help Bonney identify this bike.  He believes it may be a Triumph 5/1 with a 493 cc engine and exhaust from later model


Thanks

Nigel.

[L.A.B.]

The cylinder barrel looks a bit too slender to be the 500cc model I think?

Possibly it could be either the 250cc (L2/?) or 350cc (3/?) version?

[TriSpec]

Definitely not a 5/1 as that was a side-valve model, which this obviously isn't. Not an L2/1 or 2/1, as suggested for those fuel tanks were different. Ditto for the 3/x models.
The Model 5/5 of 1935 had an optional upswept exhaust such as on this machine although the sales brochure for that year showed it to be slightly longer and slimmer; not that that proves anything, for sales brochures were notoriously inaccurate when compared with machines as actually made. The 1935 Model 5/5 came with the foot-change attachment as standard and thus the tank did not require, or have, the threaded mountings for a handchange gate.
I would say that this was most likely a 493cc 1935 Model 5/4 with the optional footchange and an upswept exhaust, which may or may not have been supplied by Triumph.

Cheers, Peter C.
(Triumph specialist for the VMCC of Britain)

[L.A.B.]

Definitely not a 5/1 as that was a side-valve model, which this obviously isn't. Not an L2/1 or 2/1, as suggested for those fuel tanks were different.

I couldn't say if it's definitely a 2/1 or not, but there's a photo of what is described as a "2/1" (no year info given) in Ivor Davies' book 'It's a Triumph' which appears to have that style of tank. The hand-change mechanism appears to have been removed from the bike in the photo above, and the gearbox looks different,  the book photo bike has a low level exhaust system but it is very similar otherwise.