Well i got my 45t rear sprocket for my 03 speedy today and it doesn't fit with the stock chain (it was a mixed review if it would fit, so i knew it was a 50 50 shot) . So my question is do i buy a new chain or buy a 17t front sprocket (stock is 18t), My chain is showing no signs of being wore out and it would be a pitty to spend all that money for a chain then ended wanting the 17t any ways. I have done a ton of reading on this it seems that the 17/45 combo gives a 14% increase in over all torque and makes for a hell of alot of fun. The down side would be it puts you in high rpms when cruising down the highway and lose top speed but i dont care about that (no need for 160mph). From what i understand 18/45 is a good middle ground. But how big of a difference am i going to feel from going from 18/42? For $50 it was worth gambling trying out 18/45 but im not wiling to gamble another $150 for a chain to find out.