What's best for a hilly area?

Electrically assisted bikes, trikes, etc.
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asinus
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What's best for a hilly area?

Postby asinus » 12 Nov 2017, 11:21pm

Living in North Lancashire, a pedelec that climbs steep and long hills well would be useful - for instance, for getting up to the start of a hill walk. Is there any decent information about what type might be best? Crank or hub drive? Presumably torque rather than cadence sensor. Any advice on gearing? Wheel size? Any other tips? Can't afford to sacrifice much range either . . . Or am I asking about something that doesn't exist?

kwackers
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Re: What's best for a hilly area?

Postby kwackers » 13 Nov 2017, 9:21am

I would say a crank drive will always outperform a hub on hills mainly due to being able to change down. With a crank drive, wheel size etc becomes irrelevant, you can alter the gearing to suit the general riding you do.

Cadence sensors are fine, we all have a cadence we prefer.
Mine alters the cadence depending on the assist so I use a combination of gears and assist to set the effort. (You can also reprogram cadence etc for the various assist levels).

hemo
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Location: West Sussex

Re: What's best for a hilly area?

Postby hemo » 16 Nov 2017, 11:48pm

Bafang bpm or SWXO2 hubs are awesome and very powerful an equal to any mid drive on the road for hill climbing look for a 201 -250 rpm speed motor rating.
A cadence/pas sensor makes for a nicer ride esp if your legs get tired as it only requires a gentle pedal rotation to kick in to whoosh you along, torque sensing is quite rare and does require more serious effort. Hub max speed is regulated by the motor rpm generally a 201 rpm will do 15/16 mph and a 260 - 290 rpm hub will do about 19/24 mph, there is a 328rpm hub which will do about 27mph but this is only suitable for 20" wheels or smaller or for areas that are totally flat as it lacks torque climbing ability and will stall and get very hot all running at 36v if you over volt a 36v hub using 48v battery then speed and torque increase by 25%.

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asinus
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Re: What's best for a hilly area?

Postby asinus » 17 Nov 2017, 4:14pm

Thanks - but the problem is more about keeping going at maybe 6 mph up a long 1in 7 (or steeper) hill.

brynpoeth
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Re: What's best for a hilly area?

Postby brynpoeth » 18 Nov 2017, 10:06am

asinus wrote:Living in North Lancashire, a pedelec that climbs steep and long hills well would be useful - for instance, for getting up to the start of a hill walk. Is there any decent information about what type might be best? Crank or hub drive? Presumably torque rather than cadence sensor. Any advice on gearing? Wheel size? Any other tips? Can't afford to sacrifice much range either . . . Or am I asking about something that doesn't exist?


Where do you leave your bike for the several hours you are walking? Are you you scared it might be nicked?
Cycling? Of course, but it's far better on a Gillott

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asinus
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Re: What's best for a hilly area?

Postby asinus » 18 Nov 2017, 8:54pm

Quite - it's a big worry. My wife has a long Abus Sold Secure chain that's so heavy that needs a pedelec to transport it, and would hope to put that round a fence-post or tree.

MikeF
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Re: What's best for a hilly area?

Postby MikeF » 22 Nov 2017, 3:17pm

hemo wrote:Bafang bpm or SWXO2 hubs are awesome and very powerful an equal to any mid drive on the road for hill climbing look for a 201 -250 rpm speed motor rating.
A cadence/pas sensor makes for a nicer ride esp if your legs get tired as it only requires a gentle pedal rotation to kick in to whoosh you along, torque sensing is quite rare and does require more serious effort. Hub max speed is regulated by the motor rpm generally a 201 rpm will do 15/16 mph and a 260 - 290 rpm hub will do about 19/24 mph, there is a 328rpm hub which will do about 27mph but this is only suitable for 20" wheels or smaller or for areas that are totally flat as it lacks torque climbing ability and will stall and get very hot all running at 36v if you over volt a 36v hub using 48v battery then speed and torque increase by 25%.
How does that fit with this?
hemo wrote:
The legality is already there to read.
The main points ;
Motor rating must not exceed 250w.
Assist speed 15.6mph, 17.1ph given 10% leeway.
Throttle pegged at 6km/h unless you are also pedalling.
Amp rating not defined or N/A.
Voltage nit defined AFAIK but have seen somewhere 48v nom stated as max.
"It takes a genius to spot the obvious" - my old physics master

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asinus
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Re: What's best for a hilly area?

Postby asinus » 22 Nov 2017, 5:07pm

Another question, about crank drives: may have tiny chainwheels, so what are they like to pedal if either (heaven forbid) you run out of battery, or turn it off to conserve it e.g. on a long run? Are you left turning a ludicrously low gear, or does the drive go through and internal gear train with consequent frictional losses, and if so, do they matter?

hemo
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Location: West Sussex

Re: What's best for a hilly area?

Postby hemo » 22 Nov 2017, 7:35pm

MikeF wrote:
hemo wrote:Bafang bpm or SWXO2 hubs are awesome and very powerful an equal to any mid drive on the road for hill climbing look for a 201 -250 rpm speed motor rating.
A cadence/pas sensor makes for a nicer ride esp if your legs get tired as it only requires a gentle pedal rotation to kick in to whoosh you along, torque sensing is quite rare and does require more serious effort. Hub max speed is regulated by the motor rpm generally a 201 rpm will do 15/16 mph and a 260 - 290 rpm hub will do about 19/24 mph, there is a 328rpm hub which will do about 27mph but this is only suitable for 20" wheels or smaller or for areas that are totally flat as it lacks torque climbing ability and will stall and get very hot all running at 36v if you over volt a 36v hub using 48v battery then speed and torque increase by 25%.
How does that fit with this?
hemo wrote:
The legality is already there to read.
The main points ;
Motor rating must not exceed 250w.
Assist speed 15.6mph, 17.1ph given 10% leeway.
Throttle pegged at 6km/h unless you are also pedalling.
Amp rating not defined or N/A.
Voltage nit defined AFAIK but have seen somewhere 48v nom stated as max.


You make your own choice, I am just giving some info.
All lcds have a speed setting it's up to the user to keep it legal or de=restrict for a bit more speed.
With some KT controllers there is a 25km/h restriction wire, unplug it and off you go 25% more speed.

hemo
Posts: 77
Joined: 16 Nov 2017, 5:40pm
Location: West Sussex

Re: What's best for a hilly area?

Postby hemo » 22 Nov 2017, 7:38pm

asinus wrote:Another question, about crank drives: may have tiny chainwheels, so what are they like to pedal if either (heaven forbid) you run out of battery, or turn it off to conserve it e.g. on a long run? Are you left turning a ludicrously low gear, or does the drive go through and internal gear train with consequent frictional losses, and if so, do they matter?


I can't be sure but believe they have internal gearing. For 2018 the new Bosch drive I believe are reverting to a normal chain ring size.

kwackers
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Re: What's best for a hilly area?

Postby kwackers » 22 Nov 2017, 9:26pm

asinus wrote:Another question, about crank drives: may have tiny chainwheels, so what are they like to pedal if either (heaven forbid) you run out of battery, or turn it off to conserve it e.g. on a long run? Are you left turning a ludicrously low gear, or does the drive go through and internal gear train with consequent frictional losses, and if so, do they matter?

The bafang unit is simply straight through, there is no gearing.
As far as I can tell if there is any friction it's not worth worrying about.

The chainwheel it comes with is 46 tooth (I think) you can fit others if you prefer. I had a battery mishap the other day (my fault) and ended up cycling it 14 miles. TBH I can't say I noticed anything wrong with it. It did feel weird because you do get used to the way it behaves under power, without it feels fairly flat and the pedals feel heavy especially getting started but at 'cruising' speed it was perfectly fine. Even climbed a few small hills.
Ultimately because of the way I use it the assist simply means I 'cruise' a gear or two higher than normal. Without it then I simply ride a gear or two below.
Same effort, different speed.