What Darkness says and..
An L-twin will produce power pulses to a greater degree than a smooth in line 4.
I bought a chain for my first Monster many years ago but didn't fit it until I got the present Monster. I was told that I needed a special chain because of the Ducati power pulses. It was a really heavy Izumi thing.
It was fine when new but did need to be cock on for adjustment to avoid any vibration.
I didn't get a sensational mileage out of it before I couldn't stop the vibes with any amount of carful adjustment. When looking for a replacement I took advice on what to get and some were astounded at the heavy chain I was using.
I actually wrote to DID in Japan and they recommended a DID VX-2 520, which I had read was suitable for up to 750cc. In fact the power figures of the contemporary 750's are all higher than my M900, so I took their advice. It's been great, with much lower vibes, even when it's in need of adjustment now and then, due to it's much lighter weight than the previous. I think it's now covered more miles too.
The moral is too heavy is as bad as too light. The manufacturers worked out the Goldilocks chain before the bike went into production for good reason, so you will do very well to go with the chain type they specify.
Finally.. Get a case saver in there, before it's too late and sleep better.
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