Like the other 650cc models the Trophy gained unit construction in 1963. This traded some smoothness for performance as a few pounds were lost. Regal Purple replaced Polychromatic Burgundy. For 1964 the bike received stronger front forks, which improved handling. The Smiths Chronometric instruments were replaced by the magnetic type and Hifi-Scarlet replaced Regal Purple. In 1965 a locating pin for finding TDC was added to allow timing without the use of a dial gauge. Burnished Gold and Alaskan White was used for colour.

In 1966 the tank badge style changed for the "Harmonica" style to the "Eye-brow". Confusingly the model designators for the US now reverted to TR6R and TR6C. The electrics changed to 12V and a bigger 6pt oil tank added. The front brake drum was redesigned to allow a larger braking surface. Pacific Blue replaced the Gold for this year.[8]TR6C models were solid Pacific Blue with white stripes along the centre of the petrol tank, which was now a smaller teardrop 2-1/2 gal tank without the parcel grid.

[9]For 1967 the TR6 received some engine changes. Compression was raised to 9:1. and Bonneville exhaust valve and camshaft were adopted, resulting in a 5bhp increase. This year was the beginning of the shift to unified threads. Mist Green replaced the Blue for this year. The TR6C got twin high pipes on the left side.

[10]The twin leading shoe brake was adopted in 1968. This is often retro fitted to earlier bikes as shown in the bike pictured above which is a 1964 model. It provides superb braking and when setup correctly, performs as well as 70s era disc brakes. This year saw the introduction of the Amal Concentric Carburettor and [11]was the only year of the attractive "Trophy Sport" decal on the side cover. The 1968 colours were Riviera Blue and Silver. The TR6R was renamed Tiger for 1969, leaving the TR6C model with the Trophy name. The front brake used a modified actuating lever to avoid snagging of the cable on the front mudguard. Other changes included the larger RM21 alternator and twin Windtone horns. The signature parcel grid was finally dropped for all models. Trophy Red replaced the Blue with White Mudguards.