eBikes: I have some questions

Electrically assisted bikes, trikes, etc.
PH
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Re: eBikes: I have some questions

Postby PH » 27 Nov 2019, 9:22pm

1982john wrote:I think I will just have to hire one and see what it's like.

I think that's a good idea, though try and hire or test ride more than one, there's a fair difference between them.
My only experience is a few hires and test rides, plus talking and riding with e-bike riders. You haven't said what sort of route it is, where it will make a huge difference is on a route with a lot of start/stop junctions, lights and the like. There was a thread on here some years ago about why people red light jump and someone demonstrated that it didn't take many stops to equal a mile of steady riding for the same effort. I can match the top speed of an e-bike without trying too hard, that's as it should be, what I can't do is match the 0 - 10mph acceleration without really pushing. if your route has a few stops in 14 miles I think it'll make a considerable difference, partly in time but mostly in effort.

westofsouth
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Re: eBikes: I have some questions

Postby westofsouth » 27 Nov 2019, 10:07pm

The assistance tails off at about 16mph (in EU countries).
After that top speed is down to you, and gradient, head wind etc.
Same as a normal (but heavy) road bike...

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Cugel
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Re: eBikes: I have some questions

Postby Cugel » 27 Nov 2019, 10:24pm

NickWi wrote:
Cugel wrote:Have you remembered to switch it on? :-)
Cugel


If you wish to make personal insults, that's fine, fire away I've got a thick skin, but it does help the OP with his question does it. (snip)


Although tempted to make a personal insult or three, I will desist as I am nice. I'll make do with a sarky remark or two, thenk yew. :-)

As to offering advice to the OP - I thought I had - and of the more encouraging sort compared to say ... your own.

We need not advise a particular bike, as there are several factors in choosing a bike other than it's e-motor. More powerful and beefier is not necessarily what's needed. What the OP asked about was whether an e-bike (any e-bike) would enable him to increase the average speed of his commute, even though it's a bit longer and maybe hiller than his present commute. The unequivocal answer, for the great majority of e-bikes, is yes.

Cugel

1982john
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Re: eBikes: I have some questions

Postby 1982john » 27 Nov 2019, 10:43pm

PH wrote:
1982john wrote:I think I will just have to hire one and see what it's like.

I think that's a good idea, though try and hire or test ride more than one, there's a fair difference between them.
My only experience is a few hires and test rides, plus talking and riding with e-bike riders. You haven't said what sort of route it is, where it will make a huge difference is on a route with a lot of start/stop junctions, lights and the like. There was a thread on here some years ago about why people red light jump and someone demonstrated that it didn't take many stops to equal a mile of steady riding for the same effort. I can match the top speed of an e-bike without trying too hard, that's as it should be, what I can't do is match the 0 - 10mph acceleration without really pushing. if your route has a few stops in 14 miles I think it'll make a considerable difference, partly in time but mostly in effort.


There's an 11 mile version with lots of stop starts or the 13mile which is much more quiet lanes (I prefer the latter!) But yes I know what you mean - especially wen carrying lots of luggage. I'll be hauling around 10kg most days.

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Mick F
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Re: eBikes: I have some questions

Postby Mick F » 1 Dec 2019, 5:09pm

I have questions too ............ in the vein of the title of the OP.

Saw two people coming up a local hill. Single chevron, but it belies the sudden steepness.
I was waking the dog this afternoon and was walking down ..... or should I say me and the dog were at the top before descending.
The two cyclists - man and woman in their late 60s early 70s came up the hill on eBikes.

I ride that hill often - on a normal bike - and it's a struggle. Bottom gear hill and a good puff to get up.
These two people came up and it was a breeze for them. They weren't huffing and puffing like I do ........ and I'm a fit experienced cyclist.

Question:
If the eBike system is to limit the speed to 15mph assistance, is the speed up a hill and the power required to get up it, but you're doing only 5mph, is the assistance greater? Can you just "turn the pedals" to get up a hill whilst the battery does all the work?

This is the way the two people seemed to be riding up the hill. Completely relaxed and not straining in the slightest.
Mick F. Cornwall

billym444
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Re: eBikes: I have some questions

Postby billym444 » 1 Dec 2019, 6:42pm

there peddle assit, so they will help and make the job easy. but not many 250w will take you up a step hill without some work.
big Bafang fan lol

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Mick F
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Re: eBikes: I have some questions

Postby Mick F » 1 Dec 2019, 7:17pm

billym444 wrote:there peddle assit, so they will help and make the job easy. but not many 250w will take you up a step hill without some work.
Yes, I understand that, but how much do they assist you up a one chevron hill at 5mph?
How much of assistance is there to take the puff and strain away?
Can you get up a one chevron hill without being out of breath?

It seemed to me that the couple today sailed up the hill. It's a strain just walking it.
Not saying in the least that they had illegal eBikes, but it occurred to me that hills become so easy with an eBike it must take the effort clean away when riding in Cornwall. It must make the hills appear flat.
Mick F. Cornwall

rareposter
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Re: eBikes: I have some questions

Postby rareposter » 1 Dec 2019, 7:40pm

Mick F wrote:
billym444 wrote:there peddle assit, so they will help and make the job easy. but not many 250w will take you up a step hill without some work.
Yes, I understand that, but how much do they assist you up a one chevron hill at 5mph?
How much of assistance is there to take the puff and strain away?
Can you get up a one chevron hill without being out of breath?

It seemed to me that the couple today sailed up the hill. It's a strain just walking it.
Not saying in the least that they had illegal eBikes, but it occurred to me that hills become so easy with an eBike it must take the effort clean away when riding in Cornwall. It must make the hills appear flat.


Depends on the bike and the person and the level of assist (turbo, sport, tour and eco for example although various manufacturers name them differently).

I've seen the same - riding up a hill with a friend, both on our CX bikes and a couple in jeans and T-shirts cruised past us on what were essentially shopping bikes but with motors (like this one: https://www.halfords.com/cycling/bikes/ ... e-20-wheel )

e-bikes aren't about being faster, they're about lessening the effort, especially on hills and things like away from traffic lights. They make a lot of sense on a commute, not necessarily because it's faster but because minor hills, headwinds and luggage simply don't matter. You still have to put in the effort to turn the pedals, they're e-assist not electric motorbikes. But it's like riding along with a constant tailwind.

You get into a routine on them too, you'll soon learn the range you get and just like you finish a ride now and charge up lights, computer etc, you just plug it in. Most modern e-bikes have a simple charging port, it's rare that you need to remove batteries now. Go to a good e-bike dealer, see what is available and what you can try out. I doubt, from what you've described, that it'll be much (if any) faster but it will be a lot less effort which means you'll be able to do it 5 days a week and still feel fresh at the weekend.

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Cugel
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Re: eBikes: I have some questions

Postby Cugel » 1 Dec 2019, 7:51pm

Mick F wrote:
billym444 wrote:there peddle assit, so they will help and make the job easy. but not many 250w will take you up a step hill without some work.
Yes, I understand that, but how much do they assist you up a one chevron hill at 5mph?
How much of assistance is there to take the puff and strain away?
Can you get up a one chevron hill without being out of breath?

It seemed to me that the couple today sailed up the hill. It's a strain just walking it.
Not saying in the least that they had illegal eBikes, but it occurred to me that hills become so easy with an eBike it must take the effort clean away when riding in Cornwall. It must make the hills appear flat.


There are different power profiles in various e-bikes. Some give a gentle and gradual assistance that's related to your own effort, measured with strain gauges in the BB or elsewhere. To get the motor's 250w you have to output a lot of power yourself. Most of the racey style e-bikes are like this, so it still feels like proper cycling but with stronger legs. It's not easy to get anywhere near 250W assistance out of them unless you're trying very hard yourself.

On the other hand, the ladywife's has a "red" setting (top of three "on" settings) that will momentarily give up to 400W. It won't last as the motor gets hot and you can hear the battery draining with an electricity-gurgling sound, so the clever bike shuts it down again. :-) It's meant for those momentary 1 in 4s found on wicked Blighty countryside roads, especially on the inside camber of switchbacks.

Other e-bikes, especially the heavier continental tourer style with a big 70Nm BB motor and 500 or 750Wh battery, have a different profile, such that their power is readily available in large amounts even if you aren't yourself putting in a lot of effort. Some just seem to have a set-power at each setting or level of assistance and don't seem to measure your own power output. In those cases, you just have to turn the pedals to keep the power on - or so it seems.

If you're fairly fit but not enough to enjoy seriously hilly cycling (especially with fitter people) then a racey-style e-bike is ideal. It adds just enough on the hills so you don't get dropped (or can even show off a bit). Every hill isn't a serious physical trial needing an oxygen cylinder waiting at the top. If you're essentially unfit but want to cycle distance and hills then a bike with more assistance at each level, with no miserly output if you don't try hard yourself, is better.

Dandy horses for courses. :-)

Cugel

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philg
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Re: eBikes: I have some questions

Postby philg » 1 Dec 2019, 8:05pm

Mick F wrote:
billym444 wrote:there peddle assit, so they will help and make the job easy. but not many 250w will take you up a step hill without some work.
Yes, I understand that, but how much do they assist you up a one chevron hill at 5mph?
How much of assistance is there to take the puff and strain away?
Can you get up a one chevron hill without being out of breath?

Firstly the 250W refers to continuous output over an extended period - both my '250W' motors can put out in excess of 400W for quite a while.

Putting some rough numbers into Bike Calculator for a rider + ebike weight of 100kg to get up a 1 in 7 hill (14.3%) at 5mph needs about 350W. I can vouch from experience that to get one of my bikes up a one chevron hill requires a significant rider effort.

I think what is more important here is not power but torque, as if the motor cannot spin sufficiently fast when you're struggling up a steep hill, then you won't be getting anything like the rated output power despite what the controller is reporting.

That is based on observations using hub motors, I believe a BB motor will cope better as you can select a low gear and let the motor spin faster - with a hub gear this is not possible unless you apply more pedalling effort of course. I'm happy with the hub gears as I still want exercise just not the torturing kind. HTH

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willcee
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Re: eBikes: I have some questions

Postby willcee » 1 Dec 2019, 9:00pm

Mick.. with the right bike, sensible hill based gearing, strong mid motor and strong battery, hills like that are 15 mph easily with the same effort you would use to ''glass crank'' on a flat smooth asphalt surface at maybe 10 mph, that's what you witnessed.. and you could go on like that for 40 plus miles.. you should get a run on one, its addictive, like a tail wind with 2 pros on the cranks... much has been said about speed and E bikes but unless you are what i call a sunday warrior most of whom never race .. hill climbing is just so much fun compared to muscle power... and you can give those boys a nod on the way past... will

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Re: eBikes: I have some questions

Postby stodd » 1 Dec 2019, 9:06pm

rareposter wrote:it's rare that you need to remove batteries now.
I agree (and with what most of the other posters have said). But warning: it is not recommended to charge a battery at low temperatures, so if the bicycle lives outside or in a garage it is best in winter to remove the battery and charge it inside. There is a growing trend for bikes to have batteries that look neat but are more difficult to remove when needed.

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al_yrpal
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Re: eBikes: I have some questions

Postby al_yrpal » 1 Dec 2019, 9:10pm

Mick F wrote:
billym444 wrote:there peddle assit, so they will help and make the job easy. but not many 250w will take you up a step hill without some work.
Yes, I understand that, but how much do they assist you up a one chevron hill at 5mph?
How much of assistance is there to take the puff and strain away?
Can you get up a one chevron hill without being out of breath?

It seemed to me that the couple today sailed up the hill. It's a strain just walking it.
Not saying in the least that they had illegal eBikes, but it occurred to me that hills become so easy with an eBike it must take the effort clean away when riding in Cornwall. It must make the hills appear flat.


My Ortler has a Bosch BB motor. I can get up a one Chevron hill with the 2nd level of assistance Tour by selecting a no 3 sprocket on the derailier and a fair bit of effort from me. A two Chevron Hill with the fourth level of assistance Turbo and no 2 sprocket both the motor and I struggle with my 85kg and a 24kg bike. I use the gears and assistance to ensure I am getting my heart pumping and breathing hard. Its just that with the electric bike I can travel on more challenging rides and ride much further than without assistance.

Hard to answer your question objectively, just as without an electric bike it still depends on the power you can personally deliver through peddling and your personal level of fitness.

You feel like Ridley in the second Alien film when she was strapped into the powered robot. The bike magnifys your effort and more than doubles it I think.

Test ride one and see for yourself. Take a trip over here and borrow mine for a day.

Al
Touring on a bicycle is a great way to explore and appreciate the countryside and towns you pass through. What do you do to make a difference?

stodd
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Re: eBikes: I have some questions

Postby stodd » 2 Dec 2019, 9:28am

Most 'standard' Bosch motors/torque sensors have a max turbo assist of 250%. To get 500w out of it you still need to put in 200w (eg total 700w); quite an ask for any length of time for many (most?) of us. Bikes with cadence sensing don't have this limitation; if 500w will get you up a hill it can do that with no effort at all from you.

There are benefits to both systems. Are there any combination systems out there that let you switch torque/cadence modes, or even give some continuous mix? User interface would need careful thought, but I don't see why the electrics should not be very straightforward.

billym444
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Re: eBikes: I have some questions

Postby billym444 » 2 Dec 2019, 7:32pm

theres so many if and buts to the hill climbing question. fitness is a big thing. i have small hill near me but the top is very steep. theres not many 250w will get up it without a very low gear and some effort. how much effort will also be down to the rider fitness. at the end of the day, if you have a ekike that does all the work then you may as well buy a scooter.
big Bafang fan lol