My ST2 also gets over 200mi per tank. The reserve light comes on at about 150 miles .... really early. When you said you got 100 mi per tank, were you estimating based on the low fuel light? (or did you actually measure the fuel used? I think the St2 tank is about 5 USgal.)
As for the stumbling .... you need an after market chip (FIM), make sure the bike is in good tune, and I would consider drilling the airbox. Mine responded really well to more open mufflers too. (FBF Forzas)
My 2 cents.
Les
As for the stumbling .... you need an after market chip (FIM), make sure the bike is in good tune, and I would consider drilling the airbox. Mine responded really well to more open mufflers too. (FBF Forzas)
My 2 cents.
Les