Any suggestions on shorter aftermarket shock?

[pekingduck]

Stock 2013 CB1100 shocks are 360mm eye-to-eye length. There's no shortage of used 340mm long Bonneville (pre-2016) shocks out there. I've actually used them on several other bikes with fine results. I've bought them for as little as $30/pair.

The lower rubber bushing on the CB1100 is a larger ID than the top as I recall, and that's not normal so you may have to swap some bushings around.

I have a pair of 365mm Triumph Thruxton (pre-2016) shocks on my 2004 Bonnie and they improve the Bonnie's handling markedly. I might try them on the CB1100.

It would be difficult to take the stock shocks apart because there should be a jam nut above the rubber bumper, all covered by the shroud.