This is a 13" rear shock intended for a Vmax (2007) that I intalled on my 2007 SM. This shock comes with 120/170 lb springs.

I consider it a "heavy duty" spring in this application. With minimum preload it works pretty well solo for me. Preload is infinitely adjustable within the limits of the threaded collar. A small HF strap wrench is useful for adjustment.

I also tried the lighter 105/150 springs & they were just too light for this bike.

They are pretty good. I want to run them for awhile and see how they do.

Are these the same length as the stock units ?

I believe 12.5" is the stock length.

Ryk is correct. PS makes a 12.5" length 444 series shock that is intended for the BA/SM - that one uses a 125/170 spring; I don't recall the model number off hand.

Got it, thanks.