Hello JMetz, welcome to the forum.
Lowish price kits are a bit of a problem since they are so rare. I can point you to good ones that are quite expensive like the
eZee one at £895 or the
Heinzmann ones at well over £1000, but apart from the Alien kit I can only think of the
Cyclone ones that are readily available in the lower price range.
The Cyclone is a drive through the gears kit as you'll see, and not every bike can accept it for space reasons, details on their site, and it must also be bought direct from Taiwan.
As you will have gathered from this thread, it's batteries that are the problem, the best batteries costing from £400 to over £500, so they automatically make the first two kits I mentioned very expensive. Cheaper kits must use the older technology lower grade lithium batteries which are not always reliable, or the very old tech lead-acid (SLA) batteries which are cheaper and reliable but extremely heavy.
The one mainstream kit offered with those heavy SLA batteries is the Currie Electrodrive, an old design which is a bit noisy and drives the bike by being clamped to the rear wheel spokes with the motor at the side. The availablity of these has been variable, but you can inquire via
this website. You'd need to charge at both ends with this kit though, the SLA batteries won't do the 22 miles on one charge.
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