ok, heres a lowdown on chains and sprockets that may help.
there are 3 diffrent main types of chain you can get. non o-ring, o-ring, and x-ring.
non o-ring are the cheapest of the bunch. the pivot points between links are unprotected from sand and grime. this will allow foreign material into the link pivots and cause huge amounts of excess wear in the chain. more wear = more replacement cost in the long run. you will go through about 3 of these as compared to one o-ring chain.
o-ring is the same design as above except for the addition of small rubber rings placed in the pivot points to act as a gasket. these rings require lubricant about every 30 hours of ride time to keep them in good shape but will last much longer than a standard chain.
x-ring are the upper end chains used in mose racing applications because they keep out more dirt and mud and hold their lubricant inside better than the standard o-ring. the shape of the gasket is not a smooth circle ring but has grooves in it to help hold a better seal. these look the same as a standard o-ring chain but are 3-4 times better. these chains will last you quite a while if cleaned regularly.
chain cleaning and lubrication- the numbr 1 killer of a chain is failure to take care of it. any time you ride through sand or mud you should clean the chain after the ride to prevent excess wear. there are several diffrent cleaners on the market that work well. invest in a grugde brush and some good cleaner. most cleaners are in an aerosol can and as long as it says o-ring safe you are clear to use whatever you choose. DO NOT use engine cleaners or gasoline to clean a chain. it will destroy your o-rings and ruin the chain. Kerosene is a preferred cleaner as well and is usually the one recommended by the manufacturer. its a simple process. soak chain, scrub with brush while rotating the rear wheels by hand and rinse with a water hose.
now that your chain is clean, you need to replace the lubricant that you just removed. most cleaners will strip all lube from a chain in the process. there are 2 diffrent kinds of preferred lubricants for a chain. ChainLube and ChainWax. the proper way to apply either is to clean the chain and then dry off the excess water. ride the bike in a clean sand free area for about 5 minutes to heat up the rollers of the chain then park it. once the chain is warmed up, coat with lubricant and wipe the excess off with a towel. then let it sit for about 15-30 minutes to soak in to the joints evenly.
ChainLube- these are usually a thin lubricant similar to WD-40. they spray on easily and fling off just as quickly once you ride. chain lubes need re applied often and should be replenished after each ride.
ChainWax- These are a thicker wax based lubricant that is also applied from an aerosol can. the chain MUST be warm before application for it to give the best protection. Once chain wax is applied, wipe off all excess with a towel and let it sit to "dry". once its ready the wax will leave a sticky non-fling coating on the chain and is good for a few rides before it needs cleaned and re-applied. This is the most common lubricant used in high performance street bikes and high horsepower drag bikes due to its resistance to flinging off the chain. although, if you are in the desert like i am you will need to clean the chain at the end of each time spent in the sand due to its sticky nature.
Both types are available at your dealer for under $10 a can and will double or triple the life of your chain. you can never keep your chain too clean. clean and lube it often and it will last you a long time.
Sprockets and chain sizes- Rule number 1 when replacing a chain or sprockets. NEVER EVER replace one without replacing the others. change all three parts at the same time (front, rear sprockets and chain). they will last longer if you do this. it is a proven fact!!!! when you use worn out componets with a new one, it causes the new componet to wear in an un-even way and you just wasted your money while possibly risking a broken chain and engine case in the process.
there are diffrent sizes of chain as well. the most common used on an ATV with less than 50hp is a #520 where a 200hp superbike will use a #530. the higher the number, the stronger the chain and the more resistant it is to streching. but it is also a much heavier chain as the side links are thicker. you CAN NOT use an unmatched chain/sprocket combo safely either. this will cause a chain to break prematurely. all sprockets are made in sizes to correspond with a chain size. 520 chains require 520 sprockets while 520 chains must have 530 sprockets.
Gearing changes with sprockets- the most common way to increase performance is with a gearing change. sprocket changes allow the rider to fine tune his machine to the type of riding he/she does. but, doing so also has its dis-advantages. re-gearing a machine to give you more low end acceleration will take away from your top speed while gearing it for more top speed takes faway from your acceleration. Sprocket changes are also used when changing to a smaller tire size over stock. with a smaller rear tire diameter, the overall gear ratio of the ATV will be lower and take away from your top speed. the stock rear tires are 21 inch baloons. if you were to go to a 20 flat rear tire you will also need to get diffrent size sprockets to maintain the same top speed.
Front sprocket- the front sprocket on a stock blaster is 13 teeth. if you were to want more top end speed you would get a sprocket that is larger and has more teeth. if you want more bottom end, you would get a smaller one. the front sprocket is the most common one changed due to its accessability and the fact that you dont need to get a longer chain to change it out. a stock chain will have enough slack in it to accomidate a larger or smaller front sprocket. changing this sprocket will also give you a more drastic change in acceleration or top end. 1 tooth on the front is equal to 2.5 teeth on the rear.
Rear sprocket- rear sprockets work opposite of the front ones. going bigger in the rear will give you more low end while going with less teeth will give more top end. rear sprockets are usually priced according to tooth count and get more expensive as the bigger you get. you can get these in aluminum as well to save weight but b careful if doing so. aluminum sprockets require proper chain tension or they will wear out at an amazing rate. rear sprockets usually take more time and effort when replacing as well thus making them the less popular choice.
hopefully this helps a few of you out. feel free to PM me any questions if i missed something.
