16T sprocket, how much top end?

[mickey400ex]

Im trying to figure out ways to get my ex a lil bit more top end speed to outrun other ones lol, i was thinking about a 16t front sprocket, on average how much more top speed am i looking at? Also will i need to replace the rear sprocket as well due to the new front one? or is it ok to have 1 new sprocket and 1 used one?

[tar]

I would leave the front sprocket the stock tooth and just buy a lesser tooth rear sprocket. I don't know if a 16t would even fit.

well tat small of sproket will increase top end quite a bit.. but will hurt you BADELY off teh line

16 is huge for the front....it wouldntt be good for accelration..you would need like a 1/2 mile to get up to speed mabey a mile

[mickey400ex]

im really not worried about low end power, every race i get in always end up in a top speed run, plus my buddy just got his carrier fixed and has been talking smack on his ex, so now i want to leave him in the dust on top end and not tell him about the gear change

a carrier wow what a bad@$$ that wont have an effect its not like he is adding hp....u will beat him with the 16 now...but unless you have a LONG straight away dont gear to a 16 tooth in the front...mabey 15

Id say a 13T front sprocket

[mickey400ex]

ah he knows it didnt add any hp, me and him go riding all the time and we always race on the highway and both machines are identical, i just want to pull away from him so i can give him hell about the yellow ones are faster :p

[400exstud]

Originally posted by #1contender
Id say a 13T front sprocket

That would give you lots of low end but you wouldn't even see 60 mph.

if you guys are both stock
only increase one tooth
that will give you the edge fo sure

[mickey400ex]

so does anyone know how many mph i will hit with the sprocket, and will i have to put a new rear sprocket on due to the front one is new

[JOEX]

Originally posted by mickey400ex
so does anyone know how many mph i will hit with the sprocket, and will i have to put a new rear sprocket on due to the front one is new
http://home.earthlink.net/~gellett/400ex.htm

That will help determine the difference in mph with sprolets and gearing but real-life data will proably vary.

If your current sprockets and chain have a fair amount of time on them i'd replace the set.

[mickey400ex]

according to the chart, a 16t will give me about 5mph more on topend?

[JOEX]

Originally posted by mickey400ex
according to the chart, a 16t will give me about 5mph more on topend?
Yep, 'about' 5 mph.

I belive this calculator is just a mathmatical calculation based on the mechanical gearing of the vehicle and I don't think it takes into consideration the variables of the real world, i.e. wind resistance, weight differences, inclines/declines etc.....

A couple things to take note of: the default RPM on the calculator for the 400ex is 8250. I think the stock rev limit is 9100 RPM or close to that. I'm not exactly sure why that number was chosen....

The tire height is what the 'actual' measurement is, not what is stated on the sidewall.

yes i can agree with 5mph...sonunds reasonable