After putting on the 17 tooth front sprocket I noticed a big difference in top speed and first gear becomes a little more useful too
No chain mods were need for it either. I am however now looking to swap out the 56 tooth rear sprocket for something smaller to even further gain highway speed. After the 15 to 17 swap I now can get up to 66mph or so but that is with the engine screaming. I'd like to be able to do that speed at a lower rpm. I'm thinking of going down to a 45 tooth rear sprocket just because they are readily available on ebay. I'd like it if I could find a 50 tooth that would fit the 4-holes spaced 2.5 inches set up that the Hensim has in the rear. I'm just afraid the 45 tooth might make any off roading quite difficult. I'd like to find a happy medium.
As for other mods. The only other things I did to the engine was put on an inline fuel filter and I replaced the air box with a uni-filter. I am quite pleased with the way both of those turned out. The stock carb seems pretty good. Cheers!