Thanks, everyone.  I managed to use tongue and groove pliers (that's all I had on hand) to squeeze the rails together enough to get the seat bracket and post on it. I'm realizing that the Serfas rails are a bit thicker than the Rad stock seat rails, but hopefully the bracket will hold.

Hi all,  I'm hoping you can help. I just bought the Rad Expand 5 and the Serfas Super Cruiser seat to replace the stock seat. However, the distance of the rails on the Serfas seat are significantly (4-5mm) wider than the stock seat and the bracket from the Rad Expand seat post doesn't fit. It seems like too great a distance to try to squeeze the rails together to fit the Rad seat post and clamp; it seems like it could pop out of the bracket if too much stress is put on it while riding.

I'm new to e-bikes and I can't figure out if there's some sort of adapter I need to buy. Or, should I give up on the Serfas seat and try to find a seat that has the same rail width as the stock seat? I've attached two pics: one showing how the stock seat bracket is too small for the Serfas, and the other is a pic of the bracket that came with the Serfas, which doesn't at all fit the Rad seat post. I've seen online that others have used the Serfas  seat for their Rad bikes, but never mentioned the rail issue. Advice greatly appreciated! Thanks.  Eleni

I just purchased the Rad Expand 5 last week, but it wasn't without heavy consideration. I read obsessively about the Mini Step Thru 2 and the differences between it and the Expand. I took both for multiple test drives... originally convinced I would opt for the Mini Step Thru 2. Yes, the suspension was nice, but with the Expand, the lack suspension didn't feel terrible (most of my riding will be on trails and street). But at the end of the day, the difference in the handlebars was the decider. For me, the handlebars on the Mini Step Thru 2 were quite uncomfortable, while the Expand 5 felt much, much better.  While I'm aware that some of the components on the Expand are lesser quality, ultimately he Expand was a better fit for me.

A note about the price: I went to the showroom understanding the price of the Expand to be $1299. When they rang me up it was listed as $1499 and I told them it should be $1299.  Turns out the price change happened that day, and they honored the lower price since I mentioned it. And I was able to upgrade to the LCD display for half price. 

Eleni