Messing around with the sprockets can do many things for ones bike. For example, if you want your bike to be just a drag strip bike and cover the 400meters in a blink of an eye, you would want mad acceleration. Back in the day, my mechanic used to tell me, there is no such thing as HIGH acceleration and HIGH top speeds, unless you turbocharge your bike.
Most people would just give you the right sprocket size as the manual says, but, you can always tweak this. If you want to save fuel while cruising at a higher speed down the highway, or you need to have the acceleration of speedy Gonzalez, this is one way of doing it.
Once your bike is set and your carbs are tuned, try this:
Higher acceleration: look at the number on your rear sprocket, and tell your mechanic to get the sprockets with 2-4 numbers higher.
More top speed:look at the sprocket number, and go 2-4 sprockets lower.
Imagine your old bicycle, be it a mountain bike or any race bike, there are gears. Same concept.
For some, having a large sprocket in the rear may look nice, but what happens to your bike? It accelerates like a bat on fire but I guarantee your bike will be guzzling fuel and probably not going very fast on the highway. What do you do? You need to adjust the ratio of your sprocket by doing something about the front sprocket too.
Now, as far as charts go, I have seen some strange settings, but hey, who am I to judge right?
Ok, the general idea is this, the bigger the number on the chart, the faster the acceleration. The smaller it is, the higher the top speed. Now, on a standard bike, the ratio is usually 2.7-2.8. this will give you more acceleration and less top speed, but, in our case, a larger carb and some mods to the exhaust and intakes have fueled the acceleration. So, the best option would be to have a good balance more or less. If you are one who weaves through traffic more, please maintain the 2.7 ratio, but if you spend more of your time on the highway, you can always have better top speed by going around 2.5 to 2.4.
Now, in my case, I want my sprocket to look big so its nice and looks cool. Thus I bought a 46 rear sprocket. I need my ratio to be 2.5 so I had purchased a 18 key front sprocket. Look at the attachments I had added in and just send me a comment if you need more help with this