It's important to maintain your dirt bike chain and sprockets so you can get the most life out of 'em. Chains and sprockets are put through huge amounts of stress every time you ride so check the tension often. If the chain is over tightened the linkages will stretch and you can actually snap the chain... not good if you're stuck 25km out in the middle of No-Wheres-Ville!
Here's the best way to check your chain tension:
Tip: A quick and easy way to check the chain tension is to place your 3 middle fingers on top of each other (like a 3 fingered gun) between the chain and the back of the rubber chain guide on the front of the swingarm. You should only be able to fit those 3 fingers in. This is a good guide but won't be accurate if you have sausage fingers. Do this with your bike on a bike stand with the rear wheel off the ground.
Tightening your dirt bike chain:
The best way to lube your chain is to place your bike on a bike stand and spray it while spinning the rear wheel.
Sprocket Settings And Drive Ratios:
Depending on whether you want to ride on tight bush trails, supercross tracks or wide open fast motocross tracks you may want to adjust your sprockets to alter the low-end power or top speed of your bike.
The easiest and cheapest way to adjust the final drive, or gearing of your bike is to change the front sprocket. However, it is recommended you change both to get a better result. As a general guide, changing 1 tooth size on the front is equivalent to changing around 4 teeth on the rear.
If you replace the front sprocket with a smaller one (less teeth) you will increase low end power but decrease the top-end speed - good for tight motocross or supercross tracks. If you replace the rear sprocket with a larger one (more teeth) this will do the same.