Effect of panniers on range?

Yesterday my wife and went for a ride on our pro-connects, about 30 mile round trip, mostly flat, 7-8mph head wind on the way out and tail wind on the way back.

As an experiment I tried using the low power mode for about 80% of the ride, while my wife used mostly high and some medium. However, my battery ran down at about the same rate as hers!

The only difference (other than me being 10kg heaving), was that I had the panniers on my bike. They probably weighed about 10kg, and were quite bulky as there were some clothes in there.

So, what I'm interested to know is whether anyone else has done a comparison like this. Does the extra weight of the panniers (Plus my extra weight too) and the extra drag (if they're stuffed full and therefore sticking out to the side a lot) make a noticeable difference to power consumption?

Or could riding style differences, such as choice of gear, make a big difference, remembering that we were both going about the same speed.

I might do some experiments, and check there's no slightly rubbing brakes (there was certainly no obvious friction).

Cheers, Mike
 

flecc

Member
Oct 25, 2006
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I do know that panniers loaded with around 7 to 10 kilos makes quite a difference to consumption on my bikes in my hilly area, so therefore shortening the range, but that wouldn't be true on the flat.

I've never compared on the basis of wind resistance for my large square panniers, but I suspect that it wouldn't be serious at speeds below 15 mph, though much more so at 20 mph plus.
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Well we weren't going fast, but there was a lot of stop/start as we were just out for fun and stopping to look at wildife, etc. on the way. I guess each time setting off does the same to the battery as going up a small hill. Maybe that's where the difference came from?
 

flecc

Member
Oct 25, 2006
53,423
30,748
Yes that's very likely Mike. Acceleration and hill climbing have much in common where consumption is concerned, so that probably accounts for at least some and possibly most of the difference.
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