pstock

I am wrapping up a long (1000km) fully loaded (25kg/55lb trailer) ride from Barcelona to Chamonix.

all the way along I've had ups and downs but only the other day did I really stop to think about how to choose a route.
the last leg of the day I was seeing two A to B options: a longer 13km route that was flat it a shorter 9.5km route that had a 120m climb in it.
120m might sound like nothing - until you are towing that 25kg trailer.

so what does Physics say? is one option more energy efficient?

rm -rf

Even just riding my lightweight road bike, the flat route is much easier.
An extra 3.5km (2.1 miles) or a 120m (390 feet) climb.
The equivalent climb instead of 3.5km is probably more like 30m high. Or even less with your heavy loads.

I like scenic routes, so it's likely I would pick the climb! It's probably an interesting climb, with a view at the top.

gauvins

For rider + luggage totalling 110kgs, 120m elevation gain requires twice the energy of 5kms without elevation, according to this

Tourist in MSN

The net difference in elevation from start to finish is the same. Thus, if the hilly route involves a lot braking and the non-hilly version does not, the braking is all extra work that you did on the uphill and wasted as heat in your brakes in the downhills.

On the other hand, if you did not need any braking on the downhills because the slope was flat enough, the work would be similar.

This assumes windage and road surfaces are not considerations, comparable traffic, etc. I am neglecting the fact that speed and work are not a linear correlation. Generically, I would pick the flatter option if all other factors are equal.

Yan 

3.5km vs 120m climbing, out of those two I'd choose the flatter route, but it's getting borderline. If it was 100m of climbing I'd choose the climb.

robow

From one who lives on the open prairie, we take the wind direction / force into consideration on every ride. Generally hills tend to break up the wind, maybe for the better or for the worse, and so if I am to ride the longer flatter route, I need to know if it is a cross wind, at my back or in my face.

MarcusT

Scenery is as important as the ride. 120 m moderate climb is not that bad. Even in lowest gear can be done in about 10-15 mins. Give me hills.
With a trailer? Depends how you've been going until now

Duragrouch

Climbs can be interesting and that elevation is not terrible. But the trailer is the dealbreaker; First, it adds a lot of weight to the climb. Second, it adds a lot of weight going down, and it and your bike may not be stable at the higher speeds attained due to that weight and similar frontal area (aero drag), but a heavy trailer also adds instability, and I don't mean a little, you can get serious sway amplification depending on the trailer design. Third, if rim brakes and you need to brake going down, you can really heat up the rims. Disc brakes are far better, but you'll still wear the pads some. I wish there was an easy, safe, and feasible way to have a drag 'chute on a bike for descents, and easy retraction and stowage.

imi

Get up earlier than normal. Ride one (whichever one) of the routes. If you didn’t enjoy it, ride back and take the other route.

djb

a good an answer as any of them, I liked that!

so Mr trailer-puller, what did you do in the end or are you waiting for an internet consensus before doing it?

I'm in the 50-50 camp personally, I don't mind hills and like the views of going up and enjoy the going down, but if I was feeling tired that day, I'd go for the flatter route and a bit longer, my non-scientific take on it over decades of touring is that it takes less out of you on a flatter route.

pstock

oh I opted for the hillier route
I was close to the end of my day and knew that I could make it.
I was /am just curious about the Science (I'd there is any) of route planning
and as has been noted, the hillier route was uber-Scenic . along side a massive cliff wall most of the way.

now this was over a week ago now. I've just completed the entire ride Barcelona to Chamonix 1083kms 10750m climbing in 12 days.

the final day - from Albertville France to Chamonix - almost did me in hills-wise. only 78kms but 1873m climbing.
I thought it would be the morning that was worst. and it was tough
But the last .... 10kms was up a 362m high set of switch backs up and over Vaudagne that seemed interminable.
But it was the ONLY way to get from Passy to Chamonix by bike.



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Tourist in MSN

Congrats on having a great trip. We need photos.

djb

Thanks pstock, must be a beautiful trip, even if hard.

Really though, with climbing the issue is does one have sufficiently low gearing for your bike weight, this makes a huge difference in how your leg muscles and knees handle a lot of climbing.
And then if course how fit you are overall and we always get stronger as a trip goes along, so our climbing ability goes up the more the ride

I still think that in general, it's probably easier on our bodies with less climbing and longer flat

I don't recall the worst distance/climbing ratios days I've done, but at least now we can usually have an idea of how much climbing awaits us in a day, really easily with Google maps etc etc etc, so we can be prepared mentally with what awaits us--so starting early and pacing ourselves etc.

pstock

photos? oh my goodness there are so many

​​​​​​my original question (about Hilly or Flat) really becomes moot when you are stopping every 200m for another photo op

but I'll pull together and share a Best Of Collection.

djb

I was very curious about some of my mountainy trips, and see that seven years ago a tough day I had in Mexico was 53kms and 1833m climbing-that was a slog.
Way back in the early 90s I biked the Pyrenees and while it was back in the days of paper maps and trying to figure out meters climbed by just looking at altitudes written on map of places we were in, starting from, finishing etc and sort of adding them up, I think we had a day of about 2000m but forget the distance, probably 50 or 60k.

oh, and I find it's pretty hard to show in photos how steep climbs are.

pstock

here is a link to highlight photos.

https://photos.app.goo.gl/QqQNF72guf3dBm9R8

Tourist in MSN

I think there is a limit of 10 photos per post. I ran into a limit when I loaded a lot of photos on this site to describe something I installed on one of my bikes, but that was a few years ago, and I might have the number wrong.

Tourist in MSN

Great trip. Outstanding photos. Thanks.

That looks like a 1X system, but I see the click box on the rear hub axle, is that a Dual Drive shifted by a Shimano brifter? (I have a Dual Drive on my folder, I got lucky and learned that the Sturmey Archer 3 speed bar end shifter will shift it perfectly.)

pstock

Correct.
9S cassette and 3xSRAM Dual drive IGH
with Ultegra 3x9 Brifters
and while I have never understood shifting compatibility issues well, this setup has always work well.
I expect Bike Friday knew what they were sending out the door.

stevepusser

Physics would dictate that you won't get back as much energy descending that you expend climbing, as opposed to a flat course; because of the greater air drag at a higher speed, too.

But it's more fun, IMO.

djb

That's really quite fascinating, cassette, brifters and an igh. Very cool.
Never knew this was done, read up on it a bit and it's an interesting solution to the small wheel gear inch thing.
Re your ultegra 9 SPD brifters, they must be 20 years old--with my 9 speed tiagra brifters, already nearly 15 years old, I make sure I lube the internals regularly to keep friction down and hopefully to avoid wearing out parts one can't really change.
I'd recommend doing this regularly given their age--a whole other topic, but wanted to mention it.
Neat photos, and another guy of similar age of a lot of us.
Must have been fun as heck doing that trip.

djb

Big time! That's why I love riding in mountains, one reason anyway, I just love, love, love doing descents and especially curvy descents.
Worth all the hard ass kicking work on the way up.

Tourist in MSN

I have been using that hub on my folder for about a decade. I could not fit a front derailleur to the folder due to frame design, wanted wider gearing and that was the best option. It is a three speed hub, middle gear is direct drive, third gear is overdrive, with a 8 or 9 speed freehub. Dropout spacing 135mm, solid axle only.

In my case I bought the Sram Dual Drive hub (now discontinued) to use with a drop bar bike that I had built up years earlier, was using bar end shifter on the derailleur. And got lucky and found that a Sturmey Archer three speed bar end shifter had the correct indexing for the hub, even though it was a different manufacturer. On flat ground I am using the overdrive, this gives me much lower gearing for hills. With an eight speed cassette (11-32), my total gear range is 540 percent, with a 20.8 gear inch low gear.

pstock

​​​​​​a good tip I'll do that (lubing)
today though was "exciting" . my first post-trip non-trailer ride. and I had two flats. within. 5 minutes of each other.
but examining the puncture it was clear they were in the same position and so examining the tire I found a hole in the sidewall. undoubtedly from my pads being misaligned and rubbing against the sidewall

and I remember thinking a week ago "this doesn't look right and could be a problem" and resetting the pads on the rims.
but I evidently wasn't careful enough
and people wonder why I travel with not just pare tubes but also spare tires

djb

read up on it though before doing it, and do some searches online for various opinions on what to use.
Im not familiar with ultegra 9 speed, in terms of access to innards, etc etc, but do some looking.

for my 9 spd Tiagras, I started using a silicone based spray, and all shifting mechanisms use some sort of light grease inside, like the stuff that hardens over time and makes trigger shifters or any shifters harder to shift over time, wearing out stuff. The spray I use, called Jigg-a-Loo, is super clean, probably like any silicon based thing, but one has to spray it in more often as it is so thin.
But super easy to do, just shift and hold the shifter as far over as possible, so it opens up the space that leads to the innards, and spray the heck out of it.
shift shift shift, maybe some more spraying, and thats pretty much it

but do look up working on your specific ultegras, and as usual on the internet, expect to read all kinds of opinions including someone saying they use virgin olive oil or something daft like that. Just use common sense and read up a lot.
I figure a good lubing is better than ignoring it, and I figure it extends the life of the "high tension, contact points, gears" inside that would wear out more if ignored.

drag aobut your pads causing flat, but you figured it out, thats the main thing.
and a small wheel spare tire is even smaller than me carrying a folding spare 26in tire, cheers