So your chain needs to be replaced? How to do it? Its actually a fairly easy task if you have the right tools. And based on modern shop rates, the cost of labor to have the dealer swap out your chain will buy all the tools you'll need to do the job.
Before we get into all the how's and why's of the job, I need to first state that many shops will tell you that you need to replace your chain and sprockets at the same time, every time. This is incorrect information. If you replace your chain before its completely worn out, you're sprockets should be just fine. The old rule of thumb is two chains to one set of sprockets. You only really need to replace your sprockets when they show signs of wear. On a side note, I've been doing this for hundreds of thousands of miles on my bikes and have never had any problems from doing this.
Most of the bikes I see that are in need of a new chain have about 20-30k miles on the clock. Very rarely will your OEM sprockets be worn in that time (if you maintain your chain and it was adjusted correctly.) But check out your sprockets before you decide. If the sprocket looks hooked or worn, replace it, but if the wear is hard to notice (i.e. you have to look really close to see the wear), then your sprockets are just fine. The clear exception is aluminum sprockets; they should always be replaced with the chain because the aluminum wears much faster than the traditional steel sprocket.
Let's assume you are changing the chain for the first time and that your bike has between 20-30k miles and your sprockets are just fine. Loosen your rear axle and slide the rear wheel all the way forward, so the chain is as loose as possible.
The first thing you need to do is grind down the top of one of the links on your old chain. Do this carefully so you don't hit anything around the chain link. I like to put the link I want to grind on the rear sprocket where it will stay put. Chain breakers say that you can just install and twist and the chain will come apart. But that only really works on smaller chains or with really robust chain tools. I've watched many chain breakers crumble when they are used to break a 530, 525 or even a 520 chain. Modern chains are so strong they don't come apart that easy.
You'll want to push the pins out the back of the chain. Grinding off the face of a link removes the ‘staked' portion of the pins making it easier for you to push the pins out. If you have a robust chain breaker like the one we use its up to the task once the link is ground off. The preferred method is to use the chain tool to press out the old link. If you don't think your tool is up to the job this is where you can use a hammer and a drift. Set the drift in the center of the pin and bang away. Go back and forth between both pins so the link you are trying to remove doesn't bind up. Once the old link is removed, the old chain can come off. Be sure the bike is in neutral and just pull the chain out and throw it into the garbage.
At this point, I like to remove my counter-shaft (front sprocket) cover and clean the chain gunk that collects under there. You'll be amazed how much crap can build up there and your bike will have a greater weight savings from removing all that gunk than a titanium exhaust system. Removing the counter-shaft cover is a good chance to inspect your front sprocket. The smaller front sprocket will wear faster than the larger rear sprocket.
Unless you are lucky, you'll need to shorten the new chain. Measure four or five times before you cut. If you cut the chain too short you're up the proverbial creek and out the price of a new chain. Use the same method you used on the old chain to cut the new chain (grind and press out the link) to achieve the proper length and get it all lined up on the sprocket.
If you are a wise chain shopper, you purchased a chain with a rivet style master link instead of the traditional clip-style master link. Clip styles are just not hearty enough to handle the rigors of 100+ horsepower motorcycles. Do a search on the internet and you'll find many horror stories from riders who claim to have had their clip-style master link come unclipped at a high rate of speed or at the worst possible moment. Piece of mind is worth a lot so we strongly recommend a rivet style master link.
Your master link most likely came with the link, four little o-rings and a packet of yellow lubricant. Take your new link, install two of the o-rings, then slather it up with half of the packet of goop. Then slide the link into the chain from the back. Take the remaining two o-rings and put them over the pins, protruding towards you, and use the remainder of the lubricant before slipping the master link plate onto the link.
You'll notice that the plate will only go on a little ways. You'll need to press it into place. This is where your chain rivet tool comes into play. It should have all the parts you need to press the link together, but be super-careful here. You don't want to press the link together too tightly and you want to press from the center! If you mess this up you're master link will bind. You want to press it together just far enough to mushroom the pins.
Which brings us to the final step; mushrooming the pins to keep the master link together. Your chain rivet tool will have a special pin that has a concave dimple in the end. You probably noticed that the pins on the master link rivet have little recessed dimples punched into them. In the same way you pressed the chain together, you want to press on the lip of the link pins so that the tool pins mushrooms it. But again, be careful not to get to rambunctious mushrooming the pins. Too much force will, again, bind the link or damage the master link all together. It takes a lot of force and a fair bit of finesse. I like to tighten things, then back it off to look at the progress then tighten it up just a little bit more, then back off to make sure I don't over tighten.
Last, you'll want to adjust your chain according to your bikes manual, and lube the chain lightly. On O-ring chains, your lube provides cushion between the sprockets and the chain and protects the o-rings from o-zone, UV rays and other stuff. Also remember to lube your chain about every 500 miles or so, and to clean your chain with kerosene every 3000 miles or so for maximum chain life. Once you are done, you'll have a brand new chain, stronger than the chain that came with the bike. You'll be surprised how new your bike will feel. It will run smoother, shift smoother and be quieter. Mike thought his fuel injection system was causing him problems until he replaced his chain and the bike behaved like it was new again.