bigger tires and gear question

[joe_f7]

my 86 tecate came with some 22" tires and i think stock is 20" tires. the rear sproket is a 43 tooth on it now, and i got a brand new 37 tooth sproket for cheap. should i put the 37 on? or whats a good way to figure gears? bike will be used for trail riding/messing around racing friends

[Yamada]

With 22 inch tire and a 37 teeth rear sprocket your bike will be geared for a very high top speed ( less acceleration)
A trick to know how the sprocket size affect your gearing is to think about a 21 speeds bicycle. To smaller the rear sprocket, higher the top speed will be ( if your engine have enough power).

[iamschme]

if you go up 1 tooth on the front, it is like having a 2" taller tire on. which means that since your tires are already 2" taller than stock you wil have less acceleration unless you go down 1 up front.

if you have plenty of power try the 37 but my suggestion would be for trails, go down 1 tooth in the front and keep your current rear. it will give you better response/acceleration coming out of a curve or on a trail. you'll also get a better jump when racing your buddies. but on the other hand, putting that 37 on will give you a higher top end speed. i guess there is good and bad in both you just have to decide what is best for your style. 86 tecate should go pretty good no matter what.