Coil shocks

I have been giving some thought to changing my air Rear shock (Fox Float DPS Performance Elite) to a coil shock

Specialised have confirmed that there are only two which they have been tested and listed as compatible and these are;

RockShox Vivid coil 230 x 62.5 and the RockShox Vivid coil 210 x 55

What are the difference between the two RockShox Vivids above? What do the 230 and 210 refer too and what do the 62.5 and 55 refer to?

Thanks

230/210 are eye to eye measurements in mm

62.5/55 are stroke lengths in mm.

What bike is it

Stumpjumper Expert 2022

Far from an expert on this but I would have assumed that there is  only one correct eye to eye length for a frame and also only one correct stroke length. A shorter stoke length would reduce the amount of suspension travel you have.

So if you had 160mm travel with 62.5mm stroke you’d only have 140.8 with 55mm stroke. (160/62.5)*55

Stock one seems to be 190/45, so both the ones mentioned seem odd recommendations.

The recommendations came from Specialized but now I know what the numbers refer to I agree it does look odd.

I will probably leave as is

210×55 would be the correct size for a Stumpjumper Evo. Is yours Evo or ordinary Stumpy? 230 wouldn’t work.

Your bike uses a 190×45 shock. Any replacement shock would have to the same size.
I would suggest that the info Specialized have given you has been a misunderstanding of your enquiry. They wouldn’t knowingly advise that a different length of shock is fitted to a bike.