gearing

hey, i recently purchased a 92 suzuki 250r quadracer with a '75 kz400 engine. my questions is about gearing this thing. it seems like it needs to be lowered geared. i would rather it pulls super hard out of the whole, with 5 speeds i won't need much top end. i'm not going to race the bike or anything, but i would like to be able to put around a little more with it. do i need a smaller tooth count on the engine and larger count on the axle, or other way around. i have confused myself thinking about it so i figured while i sit and ponder maybe some other people can throw some opinions out there. please give me any info you can. i haven't counted the teeth yet to know what i am running, but i will. thanks

OK, to gear for more low end you can EITHER go with a smaller front sprocket OR go with a bigger rear sprocket.

To gear it for more top end you can go with a larger front sprocket or a smaller rear sprocket.

Later, Doug

You have a dilemma. It is cheaper (10-20 bucks) for a countershaft (small) sprocket. If you go down a tooth or two you probably won't have to take links out of your chain. Be careful, cuz too small a sprocket will make your chain wear quickly.

However, if you go up in teeth on your rear sprocket it will likely require a new chain. And rear sprockets are more costly. I would recommend this if your chain and sprockets are already worn and need replacing.

Its simple math. Divide the number of teeth on the rear by the number of teeth on the front. The result will get you the ratio between the two. This tells you how much one front tooth equals in rear teeth. Going down one tooth in the front, gets the same result as going up so many teeth in the rear.

If you can get a smaller front sprocket (buy or borrow...), you can try it out and then use the above info to put the old one back on and move up the right amount of teeth in the back.

Have fun!

anyone know of a front gear with 11-13 teeth? it seems the stock ones are 15 or 16. please let me know. thanks, jeremy

id go with a bigger rear sprocket,too easy to throw a chain off a small front sprocket.

i actually just found a 50 tooth rear sprocket, mine has a 39 tooth. so it should make a difference. but i need to get it running right first, otherwise the gearing won't matter anyway. thanks for the help.

thats a little more of a jump then i would reccomend in one big jump.get it running right 1st then try jumping a couple teeth at a time otherwise you might end up with a stump puller that runs out of steam in 1st 30'

from what i could find, the stock ratio for the original 250r was 12/42 = 3.50, and this would give me 15/50 = 3.33. so they really aren't that far apart. the only other rear sprocket i can find is a 42 tooth. but a 50 i think will be better than the 15/39 = 2.60 , that i have now. right??