The nail in the coffin for my old Thunderbird 1600 was when Triumph announced they were doing a limited run of factory fitted big bore kits and two new colour schemes. This was back in November last year when it was still hard to get any details about cost or whether the two new colour schemes would be included with the big bore kit or an optional extra. I sold the old bike there and then, after only 531 miles, and used the money as a deposit on the yet to be launched 1700.
[image title=”Thunderbird 1700″ size=”medium” id=”335″ align=”left” linkto=”full” ]
Four months later, in late March, I picked up my Thunderbird from Bulldog Triumph, in Twyford. The time had finally arrived to find out whether that extra 100cc would make its presence known. I had already told the shop that if I wasn’t happy with this one, I would be back for a Rocket III Roadster.
After nearly 1200 miles and six weeks of use, I have to say, the big bore kit makes a huge difference.
With the 1600, you feel compelled to change up through the gears quickly and at relatively low revs, whilst the 1700 is quite happy to linger in gears and feels content to use the full range of the available revs.
[image title=”Thunderbird Performance Curve” size=”medium” id=”330″ align=”left” linkto=”full” ]
The graph to the left shows the difference in power delivery. The 1600 reaches peak torque around 2700 rpm and then slowly drops off whilst the 1700 reaches peak torque a little later – at around 3000 rpm – dips a little and then hangs on to the power until around 3500 rpm. Whilst this shows the 1700 has more power, I think the following describes how and why the 1700 feels more comfortable to linger in gears. The 1700 exceeds the 1600’s peak torque sooner, at around 2400 rpm, and continues to exceed the 1600’s peak torque until around 4000 rpm.
For me, Triumph are onto a winner with the 1700 and my local dealer will be sorry to hear that I won’t be getting a Rocket III Roadster any time soon. The 1700 is for keeps!