Electra single speed to three speed.
 

I have a 2020 Electra Cruiser 1 and just picked up a NOS three speed Nexus hub/shifter. It came with everything but the cog. Can I use my existing 22T cog and single speed chain? I was thinking about going to a 20T or even 19T as I live in FL and this will be for just some neighborhood/MUP all flat type riding. Anything else I need to be aware of to install? I'll be having my shop do it and hope it's not too complicated.

Thanks for any input.

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Do both hubs have three divots where the cog slides on?

Thanks for the input.

I'm not sure, I'll have to look as the Nexus hub hasn't arrived yet, I just bought it yesterday. If they don't match should I take this as an opportunity to change out my cog at the same time to a 18/19/20T based on where I ride (all flat)? Also, with the three speed hubs, do the same single speed chains work? I'm assuming they do as there is no cassette where thickness may matter?

Single speed chain is fine, nexus hubs accept the same rear sprockets as your single speed.