It's dirty work, adjusting motorcycle chains. At least, it is on my bike, which gets cleaned exactly as often as it rains. There's also a bit of back and forth trying to get the right amount of chain slack - and that's where this jigger helps. Chain Monkey clamps onto your chain and gives you the correct chain tension first time and every time. Simple, effective and a good idea.
Generally, adjusting your motorcycle chain involves a bit of stuffing around. Play with the adjusters, check the slack, play with the adjusters again, damnit gone too far… Repeat until fingers thoroughly blackened with chain lube and sprocket grime.
My Triumph Speed Triple makes this process even worse; its single-sided swingarm uses an adjusting collar in behind the sprocket carrier, which needs to be adjusted in tiny degrees, but takes quite a bit of effort to move, so it's incredibly easy to overshoot the mark. You also tend to need to adjust the chain a lot, because … well, it's a Speed Triple, and it's very fond of preserving the front tire by holding it up in the air.
So I reckon this device might get a fair bit of action in my garage. Chain Monkey is a very simple idea that ensures a consistent correct chain tension every time.
Using a little table, you work out what setting you need to use for your chain and the amount of slack you need. The settings are weirdly far apart for something designed to help deliver precision, but you can work out exactly where it needs to be with a bit of thinking. You then set the Chain Monkey to that setting and wind up a little rubber ring to act as a stop.
Then you clamp it onto your chain, and wind it up to that stop, which puts a little bend in the chain - and then you simply adjust the chain until you can't tighten it any more.
Pull the chain monkey off, and presto, you've got the perfect amount of chain slack. Simple, consistent and effective. I quite like it.
Two things, though. Firstly, don't leave the Chain Monkey on your chain and try to push the bike away, because it doesn't like that. Clearly this is something only an idiot would do. I did it the very first time I used it.
Secondly, the rubber ring stop isn't the best solution here. It can slip when you're doing it up on the chain itself, and that means you might find yourself dialling in too much slack. I'm going to pull this thing apart and replace that ring with a nylock threaded nut that'll stay where it's told to. It's odd Tru-Tension didn't use one of these to begin with, because they use a proper nut on the go-kart version of the Chain Monkey.
So there you have it. Simple jigger but a good idea. Could probably be executed a bit better, but in its current form it's still very handy. Is it worth the US$35/AU$65 pricetag? I guess that depends on how much chain adjustin' you do.