After questioning the 150mpg claims of the Thunder Star TDI sportbike the other day I did a little research on the subject. It seems the TDI technology is pretty popular in Europe and VW claims their 3 cylinder TDI diesel gets 90mpg, and that’s in a car! The problem with TDI over here in the states is that the more highly refined low sulfur diesel fuel necessary for these engines isn’t readily available and the less refined fuel leads to higher emissions which will not meet EPA standards. Right now, VW can meet standards in 45 states. The TDI engines are also a lot quieter than the diesels we’re used to hearing making all of that clatter under the hood. So, the fuel isn’t available here because the engines don’t require it and the engines aren’t here because the fuel isn’t available. Hmm… do you see a problem? Actually, I’m not sure why the fuel hasn’t been available, it could be a refining capacity problem or low demand compared to Europe since gasoline is a lot higher priced over there. VW is working to make the diesels emission compliant anyway and the low sulfur fuel is supposed to be available by 2007. If that’s the case, we may be seeing more development in this direction for both cars and motorcycles and bikes similar to the Thunder Star 1200 could start showing up. I’m all for it. With mileage like that, I wonder why we haven’t seen a push in this direction sooner. TDI seems really interesting and I’ll be digging into it to find out more. Stay tuned.