im goin to put a 14 tooth front sprocket on my 300ex is their a way to adjust the chain so it is looser.do i need to put in another link?has anyone done this what is the performence like

 

Unless you have your adjusters already backed off all the way, just back them off when you get ready to change sprockets. There should be more than enough adjustment to allow for a 14T. I run a 15T on my Warrior which is two larger than stock, and still had enough slack. I had to adjust it slightly even then.
As to performance, if you're running stock sized tires, you'll lose a little low end torque & gain a little on top.

 

i looked and where are these adjusters what do they look like

 

Since I ride a Warrior, I havent had occasion to look at the 300ex, but my adjusters as well as those of many other bikes & quads are two 10mm bolts with a lock nut located at the rear axle, one to the right of the sprocket and the other one to the left of the brake rotor. Loosening the lock nut allows the bolt to be turned in or out, thus moving the axle towards or away from the c/s sprocket. Turning the adjuster bolt clockwise tightens the chain.. counter-clockwise allows the axle to be pushed to the front, thus loosening the chain. Of course you have to loosen the axle bolts first so it will move. Don't you have an owner's manual? It should show how to do this. If you don't have one, I'd strongly suggest you get one. I would save you much money and pay for itself quickly.

 

yeah my dad {im only 13} ordered the wrong one the on for the 300 4x4 no the 300ex does it have to be that hard to do it youed think loosing a chain would be easy.

 

Get yourself a manual!!

 

If you have a 300EX, and want to adjust the chain, rear of axle, 2 bolts, both allen-head, loosen them up, put a bar in the slots of the axle adjuster on the left side, push it forward to loosen, change your sprocket, pull the bar back to tighten, set the proper amount of slack, tighten the allen-head bolts and ride.