Hello Aardvark5. Hopefully you can help me with some advice from your experience with the Cyclotricity kits. I have recently purchased the Cyclotricity 250w front kit and I am very happy with it for my every day commuting on public roads, but on the very steep off-road uphills with a gradient of above 13%, it can be quite a struggle. So I am thinking of getting the 500w rear kit and swapping the wheels on those ...