i just recently brought a used 02 300 ex . it has and FMF exhuast, K@N filter, jet kit and Razar rear ties in size 20-11-9. there may be a sprocket on the front. my bike goes through the gears fast and tops out quick( tops out before a stock one ). Is it the tires make me go to top end faster or is there a sprocket. how do i tell if there is an aftermarket front sprocket? . also if the sprocket is after market should i go back to stock sprocket or just change the back one also . also whats does going up and down on teeth really mean .let me know thanks. and how can i even the sprocket sizes up to gain speed.
Alex

 

Think of it like your 10-speed. The bigger the front sprocket (more teeth), the harder it is to pedal (accelerate) but you have more top speed.

Its opposite in the rearend. The smaller the rear sprocket (less teeth), the harder it is to pedal (accelerate) but you have more top speed.

Conversely, the smaller the front sprocket the harder/quicker you will accelerate, but you will lose top speed.

The bigger the rear sprocket the harder/quicker you will acclerate, but you will lose top speed.


The only other thing you need to know is that the front sprocket is a coarse adjustment, where one tooth either way will make a big difference. If you want a fine adjustment, you would change the number of teeth on the rear sprocket.

Tire size also has a lot to do with it. I recently put the stock tires back on the 250r (holeshots had nozzle leak) and the top speed went way up. Acceleration seems roughly the same in the first few gears, but I can barely get it to pull through 6th (you have to really wind out 5th). But man, if you can get it to wind through 6th it feels like its doin at least 80.

So with tires it goes like this. The larger the rear tire, the more top end you will have but it won't accelerate as hard/quick. The smaller the rear tire, the harder/quicker it will accelerate, but you will lose top speed (it will go through the gears too fast and top out too soon).

Hope this helps.

 

I believe the stock front sprocket on the 300ex is 13T so, count the teeth you have on yours to determine stock vs aftermarket. 22" were the standard size OEM tires on the 300ex, so if you're running 20" Razrs, you would need to either increase your front sprocket by 1 tooth to get higher top speed, or decease your rear sprocket by 2-3 teeth to accomplish the same.

 

ok so if it is stock size 13 then got with 14 sprocket but if it is less than 13 like 12 or something then go to a 14 still?
let me know thanks. the back is a 38 which is stock i can see that . i prolly cant cehck the font till friday have to work till then. so let me know what to do. thanks
Alex

 

figure out which size front you have now,,,,,

then get one size larger

I thought stock was 14t (its been a while)

 

stock front size is 13 i looked it up. so no matter if it is stock or after market go up one size right ? let me know
Alex

 

Go up to a 14T and you'll pick up a few MPH on the top end.