Originally Posted by
Happy Feet
All of that might be relevant if one were only touring uphill but most people know that the ups and downs and flats create an average.
No one is really hiking 35lb's of gear on their back 100-160km's per day, day after day.
The toughest climb I have done recently is out of Kamloops westbound onto hwy 5 to tje brake check pullout at the summit. It took me about 1.5 hrs of hard grinding but would have taken nearly 1/2 a day to walk. After the 1.5 hour grind I continued riding another 100km's to Merrit. Something no hiker would/could do.
I completely agree WRT an overall loop ride on asphalt. No one is arguing that there is a more efficient mode of human-powered transport than a bicycle. However, the general point was made (and I am paraphrasing) that on a steep grade, at some point, a bicycle's mechanical advantage will be more than offset by it's own weight disadvantage. For some reason, this valid comment ensued into a one-sided dog pile as if the bicycle were always able to retain a net mechanical advantage up any hill.
So, while I might a agree with Doug's specific example - hike 35lbs vs bike ~65 up a 6% grade - and prefer the bicycle as well, I think the efficiency (i.e., effort/energy) analysis vs walking is going to be a whole lot closer than a layman's extrapolation of his uphill 2x pace.
For my personal case - hike 20 lbs vs bike 50, I have absolutely thought about how much easier it would be to hike up some grades. I can now guesstimate my cross-over point to prefer hiking 20 lbs might be a 7-8% grade. This is based the empirical finish times of the 5th place females - who are certainly fitter than I, and I'd bet most of us here - with their run 0 lbs vs bike ~20 lbs time equilibriums on an ~10% extrapolated grade (i.e., runner beats cyclist by ~10% on an 11% grade, so should be ~even on a 10% grade).