I hope to buy a 45 lb kayak and tow it with a cart behind my Radrunner Plus.  What is the towing capacity of the bike?  Tongue weight maximum? 

Is there concerns on how long my kayak is?

Has anyone done this?

Thanks,
Harris

When I was young I had a Schwinn stingray with a banana seat.  It was very comfortable, more narrow unlike the Radrunner's wide seat.  Has anyone put a Schwinn Stingray like banana seat on their Radrunner, if so what are your impressions?

Yes, ebay fees were withheld on the return.  It was around $16.00.

I decided to buy the seat on ebay by hipofighter18 (just like https://www.ebay.com/itm/225037218951?hash=item3465437487:g:qicAAOSwVShil~g9). 

When I got the seat, there was a letter (see: https://photos.app.goo.gl/LHnUqd14frBw3Za68) that said the seat was for a "super 73" seat.  The bolts did not reach thru the frame, there was no way to attach it properly. I contacted hipofighter18 and they responded that I was supposed to widen the bolt side hole large enough to get the bolt on.  This would weaken the frame, (stiffness is very important for a electric bike).  I asked if it were possible to replace the bolts with longer rod but the response was that I would have to take apart the seat to do that in order to replace the bolts with rod. 

While I had the seat on the bike I sat on it and it flexed (in a bad way) because there was no support at the seatpost. 

Given all that, I decided to return the seat.  This cost me around $16.00.

I would not recommend the seat.

I figured out a way to lock the Radrunner + up without modification.  I am using:

OKG Maximum Lock Chain Hexagonal Heavy Duty Security Chain and Lock Bike Chain Motorcycle Chain 5 ft x 15/32 Inch
Kryptonite New York Lock Standard (STD) New-U Model With U-Bracket 9/10 Security

Hooked up the way I show allows for enough slack in the chain to go around a fixed object.  No holes thru the wheel skirts. Hope this helps.