I dont get different sprockets... Seems like snake oil?

[gsJack]

Best sprocket size depends on the weight of the rider, year of the bike, whether stock or modified, rear tire size, and the use you intend to put it to.  I put approx 40k miles on my 97 GS with stock sprockets and then 40k miles with a 15T front sprocket.  The stock 97 needed the 15T to get started smoothly on steep uphills without very excessive engine revving and clutch slipping with a 230-240# me on board.  I did 400-500 mile interstate days at 70-80 mph indicated with the 15T sprocket and didn't find it objectionable.  In fact I use to run in 5th with big twin friends on freeways before and after the sprocket change to match their roll on speeds, did better after.  I never felt my current 02 GS needed a sprocket change with it's stronger mid range with the 3 circuit carbs replacing the 2 circuit ones of the 97 for the first 86k miles I put on it.  Last chain replacement recently I decided to try the 15T front and after only about 700 miles on it so far I think it's worthwhile for me.  Feels like it pulls stronger in 6th now on the 50-60 mph back roads than it did in 5th before and I find myself using a gear higher climbing hills on frequently travelled roads.  I like it, I don't travel much anymore and I find myself using 6th again sometimes.