Will I feel a power gain??

[motox92]

I was riding with a few friends today, on 250fs..I was on my 400ex....I was in front of them the whole time. Just want to be a little faster. I was looking at a 14th front sprocket stock in the back, the sparks timing key, and 450r front shocks..Will I notice any gains in power?

[BlasterEaten250]

The 14 tooth front sprocket will help a lot

[matt14c]

By looking at your sig. I would throw an air filter either KN, UNI, or Twin Air in the mix also. I have heard good things about that sparks timing key. I dont have one myself but a guy i have rode with a few times and by reading what people say on here it has pretty good gains. Specially for the price. Not sure what sprocket you have now but if your going up then less low end and more top end and vise versa if your going down. More low end and less top end and you will definitly feel the difference in a front sprocket change.

[Jiggity84]

when modifying teeth on the front or rear sprocket does it put a lot of more stress on your clutch or motor? .. cause i was thinking of going up a tooth on the front cause this 400ex has lots of tourqe in the low end .. i mean u can't go 3 miles an hour without having to put it in second .. its awesome for ridin trails though .. but anyway .. how hard are they to install and do i have to buy a new chain ?

[matt14c]

No not hard to install. 6 screws I think. You will have to take off the sprocket guard and chain. I cannot remember if the stock chain has a master link or not been 7 years since I have had a new quad :( but you will want to break the chain and take it off the front sprocket then remove the case saver and then there are two screws on the sprocket then it just slides off. You can get a chain breaker at any dealer or even like lowes or home depot for cheap. Depending how many teeth you go up or down will determine whether or not any links will need to be added or removed. Just moving one in the front you will not.

[droppedmazda]

you dont have to break the chain, just loosen it up and take the sprocket off. loosen the 4 bolts on the swinger and turn the carrier to loosen it and u can get the chain off. it should be 4 bolts, 2 for the guard and saver and 2 for the sprocket.

[sc400ex_rider]

just go to 05 and up gearing. go 14 front and 39 rear that way your loosing one tooth up front and gaining one in the rear. that equals the same length chain. i think honda did that for a reason so they wouldnt have to change the chain length.

quick question on sprockets. What about going 14/36(MPH less) or 13/33(Same as 15/38 (99-04)? Just to have less to spin sprocket and chain wise. I dont know if it would be noticable but i'm curious to find out.

[jcs003]

Originally posted by FlewByU352
quick question on sprockets. What about going 14/36(MPH less) or 13/33(Same as 15/38 (99-04)? Just to have less to spin sprocket and chain wise. I dont know if it would be noticable but i'm curious to find out.

15/38 would be best. if you do the math you will see the ratio as a decimal.

15/38= .395

14/36= .389~.390

13/33= .394

these decimal ratios will convert into % changes, or distribution of rear wheel output at specific rpm ranges. i.e. low end torque, high rpm horsepower.

stock gearing is set to get the best overall performance throughout the powercurve. this is just the tip of the iceberg, but i hope this helps.

when/if i go to 18" rear should I get a smaller rear sprocket to compensate for the top speed loss? I want them because I like the snap they have with less rotating mass and they can throw a mean roost. With stock gearing though i will lose like 6 or 7mph and thats quite a bit maybe change it so its only 3mph or something?