Shopping for a friend

[Barbara_Reed]

Ok, some advice needed here. It's about gear ratios and climbing hills without EVER having to push. So, I'm looking for a trike (has to be a trike) for someone who wants to do Camino de Santiago which includes crossing the Pyrenees and a couple of other decent hills. He has balance problems and some leg weakness. He can do 10 to 15 km then has to take a rest. He will have some luggage, not a lot but some. Obviously e assist , he will be on easy tracks and roads. As trikes are practically impossible to push he won't be getting off.
I'm thinking hub drive, as at some point he will need to get right down into the Granny gears and this would enable him to keep a full range of gears with a suitable front chainring and also allow a decent cassette on the motor wheel. Top speed on the flat needs to be reasonable with a fairly low cadence.
I've had a dealer suggest (with a 26 inch wheel) 30/46 and an 11-42 cassette. Hub motor EU road legal and a 14 amp/hr battery. He won't need a massive range, looking to do about 30 km per day, and could grab a quick recharge at lunchtime.
He's coming from USA in the autumn to do this, assuming the border is open. Then I will sell the trike for him, might even buy it for myself. With this setup it should be fairly easy to revise the gear setup for flat areas.
Any thoughts? I know it's got one more wheel than a bike but I think the gearing issue would be the same.

 

[Rosemount]

Hi Barbara


There are tricycle rear end conversions for regular bikes . The ones I am familiar with use a chain drive . This could possibly be converted with a bolt on E motor kit .

Rear Independent Drive Axle.Limited Slip.

 

[Barbara_Reed]

Hi Rosemount
Tadpole trike, (one wheel at the back, two at the front) so only one wheel needs to drive. That's a common setup.
I forgot to say, this would be a recumbent

 

[Barbara_Reed]

Bump... Gear ratios for climbing, people?

 

[Gary]

Hi Barbara.

It's really difficult to choose the most suitable gearing for another able bodied rider nevermind someone with leg weakness or disabilities. Add into that the weight of an E-trike and it becomes even more of a challenge to get right.

I've had a dealer suggest (with a 26 inch wheel) 30/46 and an 11-42 cassette.

do you mean using a double chainset and front derailleur?
Personally I do not think that is the way to go with a motor assist at all as even the most advanced front derailleurs shift the chain between rings incredibly crudely and that only increases at lower speeds or with more force and between a wide gap (your shop has suggested a 16t jump). It will also increase drivetrain wear and stress on the chain over a single ring set up. It's also yet another thing to have to maintain or possibly fail mid trip.
You can get similar gear ratios from an 11 or 12 speed cassette and single ring with no crossover gears and no front shifting.

eg. an 11 or 12 speed 10-52 cassette mated with a 36t front ring will give you just as low a lowest gear as 30x42 and 36x10 will be just a slightly smaller top gear than 46x11. We're talking 26mph instead of 30mph at a cadence of 90rpm (which is way above the EU restriction limit anyway and will only ever realistically be achieved downhill?) a cadence of 105rpm would take the single ring set up I've suggested to just over 30mph

to give you an idea of how that gearing would actually pan out in the real world the smallest gear of 36x52 would mean the bike would climb at 2.2mph with a cadence of 40rpm (Which is probably around as slowly as you'd ever want to be turning most cranks on road). and a slower speed than pretty much anyone who'd think about climbing a Col in the pyranees. (I assume your friend wants to do it at a decent pace?)
I've also descended a few Pyrenees mountains on road and TBH there's not actually a whole lot of pedalling required above 30mph even on a roadbike. But that's because it's faster to tuck and get your cornering right than pedal like hell only to have to manage speed into tight turns. Different rules apply if you're a TdF GC contender trying to reach the peleton after a mechanical

hope some of that helps

 

[Barbara_Reed]

Brilliant, thank you. That's exactly the sort of informed advice I was looking for.

 

[Nicho]

Ok, some advice needed here. It's about gear ratios and climbing hills without EVER having to push. So, I'm looking for a trike (has to be a trike) for someone who wants to do Camino de Santiago which includes crossing the Pyrenees and a couple of other decent hills. He has balance problems and some leg weakness. He can do 10 to 15 km then has to take a rest. He will have some luggage, not a lot but some. Obviously e assist , he will be on easy tracks and roads. As trikes are practically impossible to push he won't be getting off.
I'm thinking hub drive, as at some point he will need to get right down into the Granny gears and this would enable him to keep a full range of gears with a suitable front chainring and also allow a decent cassette on the motor wheel. Top speed on the flat needs to be reasonable with a fairly low cadence.
I've had a dealer suggest (with a 26 inch wheel) 30/46 and an 11-42 cassette. Hub motor EU road legal and a 14 amp/hr battery. He won't need a massive range, looking to do about 30 km per day, and could grab a quick recharge at lunchtime.
He's coming from USA in the autumn to do this, assuming the border is open. Then I will sell the trike for him, might even buy it for myself. With this setup it should be fairly easy to revise the gear setup for flat areas.
Any thoughts? I know it's got one more wheel than a bike but I think the gearing issue would be the same.

You might find this interesting:

Video: A Scenic Bikepacking Adventure on the Bowhead Reach Adaptive eMTB - Pinkbike

A 2-day adventure through the foothills of the Rocky Mountains.

www.pinkbike.com

 

[highpeakrider]

Would something like this suit with the correct gearing?
It is electric and would seem to do the range.

Jorvik Electric Mountain Trike JMT3 (250w)

The essential mountain trike. Trail-proven electric power designed for all-day, all-terrain riding. The ultimate expression of freedom. *Please note, images are for illustration purposes only and can vary as designs are updated*

jorviktricycles.com

 

[Barbara_Reed]

Thanks for the links. Wrong country, though. He will be riding in Spain, might take the trike home to USA after, though. The Jorvic wouldn't work, it's an upright. Think we might have a deal with a shop. I'll update when we know more.

 

[Barbara_Reed]

Well, sorry to have wasted your time. He has a problem that means he won't be riding the St James path after all. But I did learn a lot about gear ratios. Every day a school day.