I got tired of waiting.  Did some research and bought some tires to test.
RADWAGON 4 22x3.0 wheels are the same size as 2.5" x 18" motor cycle / moped tires.


I replaced the stock V-tires with
IRC NR53 2.50-18 Moped Tires and have been running them for 3 months as a daily car replacement.  This is 20 miles/day, 4 days/week.

They have MUCH more wet or dry grip, and are much beefier than stock.  The trade off is that they are about 1.2 mph slower due to rolling resistance which is about a 7% decrease in total range.

I also tried Shinko 2.75 - 18 tires.  These are 3mph slower and 12% less range.  They are 3 ply tires which makes them much too heavy for an e-bike.

Stock or 18x2.5" moped inner tubes work fine with any of the choices.

Good luck!

FYI:  I bought a SHIMANO 105 5700 52t 130mm chain ring for my Radwagon 4.  Some things to consider for anyone who wants to do this:

1)  The 52t chain ring is larger diameter than the stock RW4 46t ring.  The larger chain ring mimics the diameter of the chain guard plates.  The chain will therefore end up outside the stock chain ring plates by the thickness of the chain.  (Watch the cuffs on your pants.)  It still works, but it looks goofy and defeats the purpose of the chain guard plates.

2)  The stock RW4 granny gear is very large so that the derailleur does not work well with the larger diameter.  Shifting in and out of 1st gear (large rear sprocket) caused the chain to bind up and prevent the pedals from continuing rotation.  The Ebikekit / Bolton freewheels eliminate the large gear and this might work although I haven't tried it yet.  Also, it may be a solution to lengthen the chain.  I haven't tried a fix yet.

3)  If you have a full battery, or especially if you have an upgraded controller/motor, the top end speed will cause the stock gearing to be an uncomfortably fast cadence.  I went to the following website to try to calculate what gearing I'd like to have at https://www.bikecalc.com/speed_at_cadence.  I used 24" tire diameter and 11 teeth on the rear sprocket to find the delta between 46 and 52 teeth.  46t, 70RPM = 18.95mph.  52t, 70RPM = 21.5RPM which let me know that the 52t would be good for the stock high gear.  Unfortunately I didn't think about the chain length.  Weekend project I guess.....

Hope that helps someone.