You will not be able to compress the suspension enough to get the axle in line with the output shaft to check the initial chain tension at its tightest point. The suspension has to be disconnected from the swingarm – the linkage arm/swingarm bolt needs removing. However, you could use a ratchet strap over the seat between two ground anchor points (like on a ferry) to pull the suspension down and get everything in line, but it’s a lot easier and less likely to go pear-shaped if you just remove the linkage arm bolt.

You won’t be able to use a paddock stand off the rear axle to support the bike if you’re going to remove the dog bones as you need to take all the weight off the rear end. Support the bike under the engine using wood and a jack or axle stands if you haven’t got a bike lift or centre stand.

Get everything lined up like this (tightest point of chain run) and measure/adjust your initial slack to work from...



Support it something along the lines of this...



or this if you're more adventurous...

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