Triumph Trophy SE Fuel Economy

When I first got the TTSE in June of '13 I was extremely happy to find that it was quite miserly with gasoline. Even on Nevada two lane highways (read as high speed) it stayed at 40+ MPG.

That all seemed to go amok about a year ago. I have experienced wild fluctuations in fuel economy. From as high as 50MPG at leisurely paces to as low as 30MPG for no apparent reason. I have tried to analyze all possible causes of these anomalies.

Bad gas, ethanol, gas brand, headwinds, temperatures, speed, you name it I've considered it. All of these factors can and do impact fuel economy but I couldn't seem to isolate any one factor as the major contributor. If anything, it appeared to be temperature related where lower temperatures yielded worse MPG.

I finally found out why there was a change in MPG, about a year ago I got a new custom seat made! Now this may sound ridiculous but bear with me. I had them raise the seat so my knees would have less bend. A recent discussion on Facebook got me to to considering windshield height. The TTSE has an electrically adjustable windshield and I normally keep it just below my line of sight.

On a recent trip I discovered that the TTSE is EXTREMELY sensitive to windshield height (obviously if Triumph did any wind tunnel testing they either didn't test with varying windshield heights or they didn't optimize for that). With the windshield fully down I was able to average 46MPG over a 700 mile trip with a moving average of 70MPH.  By watching the instantaneous fuel consumption readout from the ECU, I was able to determine that raising the windshield by as little as 1" would drop 4 o 5MPG off of my reading!

Therein, was the root of my problem. I raised my seat about a year ago and the windshield height accordingly. That also explains why the cold weather was a high candidate for the problem. When it's cold I raise the windshield to stay warmer.

If you have an adjustable windshield take this into consideration if you are trying to maximize your range.