how do u make a more torguey 400ex

[400exrich]

I got a 400ex with a full yoshimura a k&n intake a outwears air box lid mod a sparks timming key and I took 2 teeth of the back sprocket any other suggestions with out a motor build

[Mtndew99]

Dropping teeth on the back sprocket takes away torque go down 1 or 2 teeth in the front or up like 2 or 3 in the back for more torque

[CJM]

Go up teeth in the back for torque, down teeth in the front for torque. Your gears however will be very short either way.

[coryatver]

You went the wrong way on the back sprocket. Put the old rear sprocket back on and get a 14 tooth front sprocket that works well. If you need more torque than that gives you will need to put a john deere motor in it

[beastlywarrior]

Try a fmf powerbomb header, the chamber helps relieve pressure spikes in the exhaust from a single cylinder motor. Actually really helps the low end but will be more noticeable the more restrictive the muffler is

[ish416]

Without a high compression piston there isn't much you can do to add torque besides changing the sprockets.

[81dasher81]

uni airfilter (k&n is just job security for engine builders in my opinion) stage 2 hotcam, trx or fcr 450 carb.. thats about as far as you can go unless you classify putting a cam in as building an engine.. stock gearing, or add a couple teeth in the back