What Have You Done To Your Tdm Today?

[fixitsan]

I've just got back from a tour in Germany with a mate who was riding his NC750. Same speeds, same conditions and he was consistently putting less fuel in than me at fuel stops. My best was 64 and the worst 56mpg over about 1200 miles. We only worked his economy out ionic, but it was over 80 compared to my 60 on the same fill up. Whilst it will never set the biking world alight (neither will the TDM), I had a quick ride on it and it's actually a half decent bike. His was bought for commuting, so economy was a factor over performance. As an ex niner owner, he did say he still preferred his old 900. 

 

 

I think that's always the case, there has to be some compromise, and they've compromised ultimate performance. I remember during my education doing some work on optimum thermal cycles in engines (or something along those lines), where you run engines in different scenarios and often find that despite the extra friction lost through a larger piston ring diameter, a larger cylinder can be run more efficiently sometimes. Heat generation is an issue too, it is easier to keep a lazy lump cool (and it's intakes, essential for good performance) than a highly strung small piston version sometimes making the same power.

 

There is far more too it than that from what i recall, but ultimately you can never have  good power output performance with good fuel economy, that's the main trade off.

 

Last year I went for a ride with my daughter across country, me on the 900 and her on a YBR125, mostly 50 and 60mph roads, no stresses or struggles. When we got back after 85 miles the YBR took 2.3Litres to refill, and mine took considerably more. Therefore if economy is the thing then the YBR is the bike to have !