|The trailer's own weight plus twelve frame mounted front racks for stock together came to 42 kg|
Today I went to collect some more racks for the shop. I thought a bit about this. Pulling the trailer behind the Mango obviously slows it down. While the Mango itself is aerodynamic, the trailer is not. It's a bit like pulling a parachute.
It is difficult to calculate the effect due to aerodynamics, but the effect of the extra weight of the full trailer on the return trip is very easy to notice and that's easy to calculate by looking at the online calculator. This shows that the effect of the weight alone takes about 5 km/h off my speed or, if you like, makes the journey feel like it is 15% "longer". However, the round-trip of 75 km still took well under three hours, which isn't so bad with a heavily loaded bike.
Here's a short film of the ride to the factory and back: