Re: And they said it couldnt be done(full suspension)
Shift Kit is great, eliminated a lot of the problems you had to deal with your chain tensioner and the chain coming loose when starting the bike. Obviously you have overcome those so nice job. You can't beat the ability to change gears on the fly, especially when riding trails. Mine weighs in at 61 pounds with half a tank. I understand your concern about separate drive trains but to be honest if you carry one spare bike chain and a chain breaker you will never be stranded.
I don't know of anyone that makes anything other than the stock 10 tooth output sprocket for the engine.
Thanks for the compliment and it has been a kick to ride in the dirt. I does excellent wheelies in first gear. You can see me riding it around a dirt track on our website if you care to take a look.