Is this the bike pedal chain, or the motor chain? I picked up the $5 Walmart chain tool for my pedal chain (which worked fine, BTW), but it did not fit my drive chain.
If you want to do it the easy way, you can either buy a chain breaker that will work on most drive chains from a farm supply or hardware store, or check your local bike shop. My LBS had a heavy duty Park Tools chain breaker that fit my kit supplied drive chain just fine and they let me use it for free.
Or if you want to do it at home like I did last weekend, I just watched some Youtube videos on how to remove a link without a chain breaker and did it that way. I started by putting the rivet I wanted to remove over a washer, and used a hammer and punch to get the rivet started. Once it was out far enough that the washer did not give enough space, put a larger nut under the rivet and continued pushing the rivet out with the punch.
About 1/3 of the way through, the taper in the punch was too wide to continue, so I took a nail with a wide head and clipped off the sharp end, then used that to hammer the rivet the rest of the way out. Then putting on the master link is easy peasy, you may need a pair of needle nosed pliers, but those are good to have anyway.
Using the hammer method took me about 10 minutes and a lot of sweat, it was not as easy going as the videos made it look, but still worked fine. Borrowing a chain breaker that is the right size is much easier and less prone to error.
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