If you are comfortable removing and reinstalling the S1 swingarm, on a scale of 1 to 10, with 10 being the hardest, it's a 0. At the time I reused my stock shock, and the hardest part of the whole job was removing the collar that goes through a boss on the swingarm. This comes off 2 ways.... it slides right out or it has you cursing in foreign languages.
I managed to get it out with penetrating oil and heat on the swingarm boss. All told not a terrible job, but it made a simple swap into a 2 hour ordeal.
Go for it.... worth the effort when you adjust the chain....
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