1967 Meriden Brochure
For 1967, Triumph produced a full colour brochure, printed in England for the US - I'm unsure whether there were separate ones for the East and West Coast distributors, but it seems likely that this factory-produced one was supplied to both. It shows the Bonnevilles in Aubergine and Gold colours. The Gold colour faded in the American sun and was replaced with white before the end of 1966 - only the first batch of 400 TT Specials built in September 1966 for the 1967 model year (1108 built in total) had this colour scheme.
The brochure claims the TT has "racing valve springs and high performance cams" and 11.2:1 pistons. However, the 1967 replacement parts catalogue specifies E6867 11:1 CR pistons for the T120TT and the same E4819 inlet and E5047 exhaust cams as the T120R (as discussed in my blog, the "11.2:1" figure appears to originate from a typo in TriCor documentation). Both cams were termed "Racing" by the factory and could accurately be termed "high performance". The E5047 racing profile (E3134) exhaust cam was first fitted to a TT Special engine built part way through the 1966 model year on 9th December 1965 - probably the first time the "T120TT" engine stamp prefix was used. It was soon fitted across the 650 range, as evidenced by Replacement Parts Catalogue No. 5, for the 1967 model year. The valve springs were the same "Red spot" inner (E4221) and outer (E4222) as the T120R, fitted to both models since 1966 (prior to that, curiously, they had been fitted to the lower-tuned Thunderbird).
There is no evidence that the cams or valve springs in the TT were ever any different from the ones fitted to the T120R roadster (except for a brief period part way through the 1966 model year, before it was fitted to all 650 twins). In 1967 the T120R was fitted with the same cylinder head with tapered adjusters and the bigger 1-3/16" carbs as installed previously on the TTs. The compression ratio on the T120R had been increased slightly from 8.5:1 to 9:1 in 1966. Both the T120TT and T120R were fitted with the lumpier "racing" profile exhaust cam in '67 (in place of the E4855 "sports" profile cam formerly fitted, as above). The only difference inside the engine now between the T120TT and the T120R was limited to higher compression pistons.
The brochure claims the T120TT outputs 54 b.h.p. - 2 more b.h.p. than previously claimed. The T120R also gains 2 more b.h.p, outputting 52 b.h.p., the same figure as previously claimed for the TT. While the T120R is likely to have had a performance increase as a result of the bigger carbs, cylinder head, new exhaust cam and higher comp pistons, it would seem unlikely that the T120TT would also have gained an extra couple of horses due solely to the new exhaust cam. The fact is that by 1967 the gap between engine specifications for the T120R and T120TT was significantly reduced compared to previous years. Perhaps this was why, in the November 1966 USA Sales Conference, JoMo requested a new version of the TT, with some radical changes (to be described in detail at a later date).
For 1967 there was no difference in specification between East and West Coast "B" range models. Both distributors received identical TT Specials and TR6/C "Trophy Specials". These were not like the earlier stripped-down Trophy Special West Coast desert racers, but East Coast-style scramblers, albeit with AC magneto/ET coil batteryless ignition. Stunning looking bikes in Mist Green and White with twin high level exhausts exiting to the left and similar small silencers to those fitted to the earlier T120C and TR6SC Competition Sports models.
Photo location looks like Coombe Manor, a country park not far from Meriden which was used for the backdrop for many of the images used in Triumph brochures (now a hotel and popular wedding and conference venue). "Models" were factory staff, dressed to look "American" - though they look very British to me.