Electric bikes on steep hills.

[Bob]

A relative of mine lives one one side of the Malvern Hills, and works
on the other. About 7 or 8 miles round trip.

He cycles occasionaly, but finds it a bit much to do every day because
of the steep climb in both directions. I suggested an electric bike,
but I'm not sure which one(s) to recommend. I've got a feeling he
needs a bike with a crank motor rather than a hub motor due to the
steepness of the hills.

If anyone has any experience of using an electric bike in a hilly
area, please let me know what model it was and how effective it was
(and how steep the hills were).

Thanks,

Bob.

[Steve Watkin]

For hills it's normally best to use a "crank drive" motor rather than the
hub motor variety. Reason is that the motor that drives the pedal cranks
can also use the advantage of whatever gearing system the bike is fitted
with. Meaning that the electric motor can spin freely, when it's most
efficient, even when the bike is going slowly.
Sadly not much choice now as there is only one of this type left on the
"new" market and that's the Gazelle Easy Glider at about 1400 quid !!
Expensive but nice.
The best cheaper alt. is to look for a s/h Giant Lafree because that also
used the same crank motor that's in the Gazelle.
A to B magazine carries a lot of very useful info about all sorts of E
Bikes.
Our Giant Lafree (the cheapest one, 3 speed and no suspension) copes with
most hills with only modest pedaling. Say up to 1 in 8 and harder work will
get you up a 1 in 6.

[Steve Watkin]

Gazelle Easy Glider info

http://www.gazelle.nl/nl/imagebank/pdf/fietsen/Easy_Glider.pdf

[Bob]

On 24 Sep, 13:58, "Steve Watkin" > wrote:
> Gazelle Easy Glider info
>
> http://www.gazelle.nl/nl/imagebank/pdf/fietsen/Easy_Glider.pdf

Thanks for the info Steve. The bike looks very nice. I wonder if
there's a bike shop mad enough to lend him one for a few days to see
if its up to the daily climb.

[Paul Murphy]

"Bob" > wrote in message
ps.com...
> If anyone has any experience of using an electric bike in a hilly
> area, please let me know what model it was and how effective it was
> (and how steep the hills were).

As suggested already a system where the motor power goes through the gears
is your friends best bet. I have a 2006 Giant Twist (formerly known as the
LaFree) Comfort with 5 speed gears and have yet to encounter a hill which it
cant get up. I don't know how to find gradients on line but if you know the
hill up to Downley in High Wycombe (it's called The Pastures), my bike gets
up that and other hills such as Marlow Hill, Hedsor Hill and Whitepit Lane
with no problem and that's with a rider over 100 kg and a full pannier bag
up The Pastures and Marlow Hill. It was quite slow but still much faster
than getting off and pushing (which is what many other cyclists I see tend
to do)!

Be aware that the current Giant Twist models have sacrificed the motor drive
through the gears system in favour of a cheaper less flexible hub motor
design and has not received the same great reviews as the older models.
Aside from the mentioned Gazelle Easy Glider, there are other new bikes such
as the Swiss Flyer range and Swizzbee which use motor power through the
gears but these cost even more, they are top quality bikes though.

Paul

[Roger Merriman]

Paul Murphy > wrote:

> "Bob" > wrote in message
> ps.com...
> > If anyone has any experience of using an electric bike in a hilly
> > area, please let me know what model it was and how effective it was
> > (and how steep the hills were).
>
> As suggested already a system where the motor power goes through the gears
> is your friends best bet. I have a 2006 Giant Twist (formerly known as the
> LaFree) Comfort with 5 speed gears and have yet to encounter a hill which it
> cant get up. I don't know how to find gradients on line but if you know the
> hill up to Downley in High Wycombe (it's called The Pastures), my bike gets
> up that and other hills such as Marlow Hill, Hedsor Hill and Whitepit Lane
> with no problem and that's with a rider over 100 kg and a full pannier bag
> up The Pastures and Marlow Hill. It was quite slow but still much faster
> than getting off and pushing (which is what many other cyclists I see tend
> to do)!
>
websites such as bikely will give height gained and distance covered, or
just use ordance surveys etc.

> Be aware that the current Giant Twist models have sacrificed the motor drive
> through the gears system in favour of a cheaper less flexible hub motor
> design and has not received the same great reviews as the older models.
> Aside from the mentioned Gazelle Easy Glider, there are other new bikes such
> as the Swiss Flyer range and Swizzbee which use motor power through the
> gears but these cost even more, they are top quality bikes though.
>
how many are going to be taken up proper hills though?

> Paul

roger
--
www.rogermerriman.com

[Paul Murphy]

"Roger Merriman" > wrote in message
...
> Paul Murphy > wrote:
>
>> "Bob" > wrote in message
>> ps.com...
>> > If anyone has any experience of using an electric bike in a hilly
>> > area, please let me know what model it was and how effective it was
>> > (and how steep the hills were).
>>
>> As suggested already a system where the motor power goes through the
>> gears
>> is your friends best bet. I have a 2006 Giant Twist (formerly known as
>> the
>> LaFree) Comfort with 5 speed gears and have yet to encounter a hill which
>> it
>> cant get up. I don't know how to find gradients on line but if you know
>> the
>> hill up to Downley in High Wycombe (it's called The Pastures), my bike
>> gets
>> up that and other hills such as Marlow Hill, Hedsor Hill and Whitepit
>> Lane
>> with no problem and that's with a rider over 100 kg and a full pannier
>> bag
>> up The Pastures and Marlow Hill. It was quite slow but still much faster
>> than getting off and pushing (which is what many other cyclists I see
>> tend
>> to do)!
>>
> websites such as bikely will give height gained and distance covered, or
> just use ordance surveys etc.

Thanks for the tip. I'll investigate but at first glance this doesn't look
straight forward (well not as easy as Google Maps for example).

>> Be aware that the current Giant Twist models have sacrificed the motor
>> drive
>> through the gears system in favour of a cheaper less flexible hub motor
>> design and has not received the same great reviews as the older models.
>> Aside from the mentioned Gazelle Easy Glider, there are other new bikes
>> such
>> as the Swiss Flyer range and Swizzbee which use motor power through the
>> gears but these cost even more, they are top quality bikes though.
>>
> how many are going to be taken up proper hills though?

This post relates to a person buying an electric assist bike specifically
for its hill climbing ability. In my eyes that means getting a machine
designed specifically with hill climbing as a prime consideration. No
mention was made about needing assistance on the flat. For the reasons
already mentioned, crank drive systems tend to be the most effective and
flexible design when hill climbing. While alot of people may be happy with
the compromise hill climbing performance that a hub drive bike offers (and
in fairness a few use brute force to perform reasonably well on steep hills,
at the expense of battery consumption), when hill climbing is mentioned as
the reason for the electric assist part, I think that means hill climbing
should be the principle consideration. I wonder how many hub motor bikes
would be sold if all purchasers understood the advantages of crank drive
with regards to hill climbing.

Paul

[Roger Merriman]

Paul Murphy > wrote:

> "Roger Merriman" > wrote in message
> ...
> > Paul Murphy > wrote:
> >
> >> "Bob" > wrote in message
> >> ps.com...
> >> > If anyone has any experience of using an electric bike in a hilly
> >> > area, please let me know what model it was and how effective it was
> >> > (and how steep the hills were).
> >>
> >> As suggested already a system where the motor power goes through the
> >> gears
> >> is your friends best bet. I have a 2006 Giant Twist (formerly known as
> >> the
> >> LaFree) Comfort with 5 speed gears and have yet to encounter a hill which
> >> it
> >> cant get up. I don't know how to find gradients on line but if you know
> >> the
> >> hill up to Downley in High Wycombe (it's called The Pastures), my bike
> >> gets
> >> up that and other hills such as Marlow Hill, Hedsor Hill and Whitepit
> >> Lane
> >> with no problem and that's with a rider over 100 kg and a full pannier
> >> bag
> >> up The Pastures and Marlow Hill. It was quite slow but still much faster
> >> than getting off and pushing (which is what many other cyclists I see
> >> tend
> >> to do)!
> >>
> > websites such as bikely will give height gained and distance covered, or
> > just use ordance surveys etc.
>
> Thanks for the tip. I'll investigate but at first glance this doesn't look
> straight forward (well not as easy as Google Maps for example).
>
heh attaully it is google maps, that is the maps are. most of these
sites do use google maps.

any way on the drop down window hit start drawing, put 1st way point on
start and last on the end of the hill and then click show elevation.

> >> Be aware that the current Giant Twist models have sacrificed the motor
> >> drive
> >> through the gears system in favour of a cheaper less flexible hub motor
> >> design and has not received the same great reviews as the older models.
> >> Aside from the mentioned Gazelle Easy Glider, there are other new bikes
> >> such
> >> as the Swiss Flyer range and Swizzbee which use motor power through the
> >> gears but these cost even more, they are top quality bikes though.
> >>
> > how many are going to be taken up proper hills though?
>
> This post relates to a person buying an electric assist bike specifically
> for its hill climbing ability. In my eyes that means getting a machine
> designed specifically with hill climbing as a prime consideration. No
> mention was made about needing assistance on the flat. For the reasons
> already mentioned, crank drive systems tend to be the most effective and
> flexible design when hill climbing. While alot of people may be happy with
> the compromise hill climbing performance that a hub drive bike offers (and
> in fairness a few use brute force to perform reasonably well on steep hills,
> at the expense of battery consumption), when hill climbing is mentioned as
> the reason for the electric assist part, I think that means hill climbing
> should be the principle consideration. I wonder how many hub motor bikes
> would be sold if all purchasers understood the advantages of crank drive
> with regards to hill climbing.
>
> Paul

steepness particaly on bikes is a moveable beast, ie one persons steep
is anothers hill. but yes the OP's friend is in hilly area thus will
need a bike that attaully can make it up the hills. attaully in one of
the bike mags there is electric bike section and one has a geared hub
motor.

roger
--
www.rogermerriman.com

[Alan Braggins]

In article >, Roger Merriman wrote:
>
>steepness particaly on bikes is a moveable beast, ie one persons steep
>is anothers hill. but yes the OP's friend is in hilly area thus will
>need a bike that attaully can make it up the hills. attaully in one of
>the bike mags there is electric bike section and one has a geared hub
>motor.

Hub motors with gears in them are fairly common, but I haven't seen any
that allow you to change the gear ratio (at least not while using it,
rather than by dismantling and rebuilding it).
Rear hubs with a freewheel for derailleur gears are also common, but
they won't change the motor gear, only the pedal gear.

It is possible to make a hub motor that effectively switches between
two gear ratios electrically by switching connections from wye to delta:
http://www.teamhybrid.co.uk/pages/crystalyte/motor_dual.htm
(though the link doesn't seem to work at the moment).

In theory you can do more cunning things, but I'm not sure if Wavecrest
ever delivered their "Adaptive" hub motor. At 750W it wasn't UK legal
anyway. http://www.greenspeed.us/wavecrest_electric_motor.htm

[Roger Merriman]

Alan Braggins > wrote:

> In article >, Roger
> Merriman wrote: >
> >steepness particaly on bikes is a moveable beast, ie one persons steep
> >is anothers hill. but yes the OP's friend is in hilly area thus will
> >need a bike that attaully can make it up the hills. attaully in one of
> >the bike mags there is electric bike section and one has a geared hub
> >motor.
>
> Hub motors with gears in them are fairly common, but I haven't seen any
> that allow you to change the gear ratio (at least not while using it,
> rather than by dismantling and rebuilding it).
> Rear hubs with a freewheel for derailleur gears are also common, but
> they won't change the motor gear, only the pedal gear.
>
> It is possible to make a hub motor that effectively switches between
> two gear ratios electrically by switching connections from wye to delta:
> http://www.teamhybrid.co.uk/pages/crystalyte/motor_dual.htm
> (though the link doesn't seem to work at the moment).
>
> In theory you can do more cunning things, but I'm not sure if Wavecrest
> ever delivered their "Adaptive" hub motor. At 750W it wasn't UK legal
> anyway. http://www.greenspeed.us/wavecrest_electric_motor.htm

maybe some sort of, varible drive system? the trouble is, i guess starts
to add cost and complexity to a fairly complex system any way.

also depends what the market attaully wants or needs, if there just
useing the bikes for getting up hills and against headwinds but not very
steep hills then maybe the hubgears will work with out a issue.

roger
--
www.rogermerriman.com

[Jeremy Parker]

"Bob" > wrote in message
ps.com...
>A relative of mine lives one one side of the Malvern Hills, and
>works
> on the other. About 7 or 8 miles round trip.
>
> He cycles occasionaly, but finds it a bit much to do every day
> because
> of the steep climb in both directions. I suggested an electric
> bike,

[snip]

Perhaps a question to ask before pursuing the electric route, is how
low is the lowest gear on the bike he has now? Admittedly the
Malverns are steep, but with a 19" gear they might be rideable, even
if only at 2 mph

Jeremy Parker

[Paul Murphy]

"Roger Merriman" > wrote in message
k...
> Paul Murphy > wrote:
>
> any way on the drop down window hit start drawing, put 1st way point on
> start and last on the end of the hill and then click show elevation.

I gave that a try but the results I obtained for actual climb values weren't
correct in all the examples I tried (eg The Pastures only shows as being
about a 250 foot climb) for anyone who's joined the mountain goats at the
top, it's much more than that, they don't call the area High Wycombe for
nothing! I shall go out with my GPS when I've figured out how to work it and
get the figures that way.

<snip>
> need a bike that attaully can make it up the hills. attaully in one of
> the bike mags there is electric bike section and one has a geared hub
> motor.

The geared hub motor is a bit like having a car with only one gear - it's
still a compromise gear ratio that should cope with scenarios the designer
incorporates into the bikes performance envelope. Even with a single geared
hub and adding electronic motor switching as mentioned by Allan, the outcome
is still nowhere near as flexible as simply having your motor running at
it's most efficient speed almost all the time like with a car, by changing
the gears to suit the terrain. When you look at all the electric assist
bikes that are the prestigious models (eg Swizzbee, Optibike, Swiss Flyer -
with prices to match), they all incorporate crank drive/motor power through
the gears designs rather than hub motors.

Paul

[Rob Morley]

In article >, Paul Murphy
says...

> The geared hub motor is a bit like having a car with only one gear - it's
> still a compromise gear ratio that should cope with scenarios the designer
> incorporates into the bikes performance envelope. Even with a single geared
> hub and adding electronic motor switching as mentioned by Allan, the outcome
> is still nowhere near as flexible as simply having your motor running at
> it's most efficient speed almost all the time like with a car,

Electric motors vary considerably in their torque/speed characteristics,
but AFAIK none behaves like an internal combustion engine.

[Roger Merriman]

Paul Murphy > wrote:

> "Roger Merriman" > wrote in message
> k...
> > Paul Murphy > wrote:
> >
> > any way on the drop down window hit start drawing, put 1st way point on
> > start and last on the end of the hill and then click show elevation.
>
> I gave that a try but the results I obtained for actual climb values weren't
> correct in all the examples I tried (eg The Pastures only shows as being
> about a 250 foot climb) for anyone who's joined the mountain goats at the
> top, it's much more than that, they don't call the area High Wycombe for
> nothing! I shall go out with my GPS when I've figured out how to work it and
> get the figures that way.
>
the google maps is at best a rought guide, it's still useful.
> <snip>
> > need a bike that attaully can make it up the hills. attaully in one of
> > the bike mags there is electric bike section and one has a geared hub
> > motor.
>
> The geared hub motor is a bit like having a car with only one gear - it's
> still a compromise gear ratio that should cope with scenarios the designer
> incorporates into the bikes performance envelope. Even with a single geared
> hub and adding electronic motor switching as mentioned by Allan, the outcome
> is still nowhere near as flexible as simply having your motor running at
> it's most efficient speed almost all the time like with a car, by changing
> the gears to suit the terrain. When you look at all the electric assist
> bikes that are the prestigious models (eg Swizzbee, Optibike, Swiss Flyer -
> with prices to match), they all incorporate crank drive/motor power through
> the gears designs rather than hub motors.
>
> Paul

well no electric motors have a much broader range of operation, they can
operatate at zero or even - revs, thus having a number of gears like in
a car isn't needed as much.

plus the electric motor is most effient on a low load, and high revs in
my experance unlike the car which likes high gears, and low revs.

roger
--
www.rogermerriman.com

[Alan Braggins]

In article >, Rob Morley wrote:
>In article >, Paul Murphy
>
>> The geared hub motor is a bit like having a car with only one gear - it's
>> still a compromise gear ratio that should cope with scenarios the designer
>> incorporates into the bikes performance envelope. Even with a single geared
>> hub and adding electronic motor switching as mentioned by Allan, the outcome
>> is still nowhere near as flexible as simply having your motor running at
>> it's most efficient speed almost all the time like with a car,
>
>Electric motors vary considerably in their torque/speed characteristics,
>but AFAIK none behaves like an internal combustion engine.

No, in particular many have maximum torque when stalled, but there is
generally a single most efficient speed, and a (different) single speed
where they produce the most power, and multiple gears help match this
to different road speeds.

Cyclists pedalling don't behave like internal combustion engines either,
(a single speed bike is more usable than a single speed car) but they are
also more efficient on varying terrain with multiple gears.

[Rob Morley]

In article >, Roger
Merriman
says...

> plus the electric motor is most effient on a low load, and high revs in
> my experance unlike the car which likes high gears, and low revs.
>
AIUI maximum efficiency occurs at maximum torque, which in the case of
some types of electric motor will be at very low revs, but in the case
of ICEs it's generally somewhere in the middle of the rev range[1].
Electric trains don't have gears, despite that fact that they need to
produce very high starting torque and also push out high power while
running efficiently at higher speeds.

[1] The flexibility of an engine is basically determined by the
difference in revs between maximum torque and maximum power. Some
engines don't need this - a diesel generator is designed to run in a
very narrow rev range without variable gearing[2]. Road vehicle engines
need flexibility to avoid changing gears all the time. Race-tuned
engines are designed to produce maximum torque at higher speeds, because
power is the product of torque and revs, and race engines generally need
high power at the cost of mid-range flexibility - this is why they need
close-ratio gears to keep the engine speed in the narrow power band.

[2] Different types of ICE also have different load characteristics -
generally diesels work well at high load in a narrower rev range, while
petrol engines work better at moderate load over a broader rev range.
Turbos or blowers can be used to modify these basic characteristics - a
turbocharged petrol engine is basically set up to give a broad torque
curve when conventionally aspirated, and when the turbo kicks in it
boosts the curve and pushes it up the rev range.

[3] It's a long time since I studied this stuff, so I might have
misremembered something.

[Jonathan Schneider]

Rob Morley > writes:

> AIUI maximum efficiency occurs at maximum torque

No ! For a DC/universal motor maximum torque is stationary so no.

Jon

[Alan Braggins]

In article >, Rob Morley wrote:
>Electric trains don't have gears, despite that fact that they need to
>produce very high starting torque and also push out high power while
>running efficiently at higher speeds.

What they don't do is put out the same power efficiently at much lower
speeds to climb steep hills. Low efficiency of low speed high torque
operation is less important when (a) it's a transient acceleration
starting off and (b) it isn't draining a limited capacity battery.

Having said that, there are also road vehicles that use hub motors
without multiple gears, like the Vectrix scooter or the Lightning car
(not actually in production yet), but not necessarily while using the
sort of relatively cheap and simple motors and controllers that a power
assisted bike typically does.

[Paul Murphy]

"Alan Braggins" > wrote in message
...
> In article >, Rob Morley
> wrote:
>>In article >, Paul Murphy
>>
>>> The geared hub motor is a bit like having a car with only one gear -
>>> it's
>>> still a compromise gear ratio that should cope with scenarios the
>>> designer
>>> incorporates into the bikes performance envelope. Even with a single
>>> geared
>>> hub and adding electronic motor switching as mentioned by Allan, the
>>> outcome
>>> is still nowhere near as flexible as simply having your motor running at
>>> it's most efficient speed almost all the time like with a car,
>>
>>Electric motors vary considerably in their torque/speed characteristics,
>>but AFAIK none behaves like an internal combustion engine.
>
> No, in particular many have maximum torque when stalled, but there is
> generally a single most efficient speed, and a (different) single speed
> where they produce the most power, and multiple gears help match this
> to different road speeds.

Exactly my thoughts. I specifically used the word 'bit' with knowledge that
there are fundamental differences including the points you've mentioned. The
difference in efficiency can be huge when motors are made to run under a
very wide rpm range. Bicycle gears on the other hand are pretty consistent
in terms of efficiency irrespective of whether 1st or top is selected.

Paul

[Paul Murphy]

"Roger Merriman" > wrote in message
...
> Paul Murphy > wrote:
>
>> The geared hub motor is a bit like having a car with only one gear - it's
>> still a compromise gear ratio that should cope with scenarios the
>> designer
>> incorporates into the bikes performance envelope. Even with a single
>> geared
>> hub and adding electronic motor switching as mentioned by Allan, the
>> outcome
>> is still nowhere near as flexible as simply having your motor running at
>> it's most efficient speed almost all the time like with a car, by
>> changing
>> the gears to suit the terrain. When you look at all the electric assist
>> bikes that are the prestigious models (eg Swizzbee, Optibike, Swiss
>> Flyer -
>> with prices to match), they all incorporate crank drive/motor power
>> through
>> the gears designs rather than hub motors.
>>
>> Paul
>
> well no electric motors have a much broader range of operation, they can
> operatate at zero or even - revs, thus having a number of gears like in
> a car isn't needed as much.

Not needed as much but if you want top efficiency under varied terrain,
still the best bet. Anything else is a compromise. A single gear motor bike
may be a closer match. Although there are electric motorbikes without gears
(those mentioned were at the recent New Forrest electric bike rally a few
months ago), These weigh ALOT more than electric bicycles and have massive
heavy high capacity batteries and motors rated at several kilowatts power
output, efficiency isn't so crucial for these machines.

Paul

[Paul Murphy]

"Rob Morley" > wrote in message
t...

> Electric trains don't have gears, despite that fact that they need to
> produce very high starting torque and also push out high power while
> running efficiently at higher speeds.

I think a huge difference is the fact they have a permanent power supply and
aren't limited to 250 Watts maximum motor power output (thats one limitation
for electric bikes in the EU). If a train had to rely soley on battery power
like an electric bike, I'd imagine there'd be several carriages filled just
with batteries. Additionally trains will never climb gradients as steep as
electric bikes encounter. I'm sure that if electric trains did have gears,
their starting efficiency would be higher but then the expense and
complication of incorporating such a system means a compromise electrical
switching situation is settled on instead. Points [1] and [2] looked good
and I can sympathise with [3] ;-) I gained my engineering qualification
which included the study of electric motors, quite a few years ago.

Paul

[Rob Morley]

In article >, Jonathan Schneider
says...
> Rob Morley > writes:
>
> > AIUI maximum efficiency occurs at maximum torque
>
> No ! For a DC/universal motor maximum torque is stationary so no.
>
Which goes to show I know more about ICEs than electric motors. :-)
I'll do some reading later.

[Roger Merriman]

Jeremy Parker > wrote:

> "Bob" > wrote in message
> ps.com...
> >A relative of mine lives one one side of the Malvern Hills, and
> >works
> > on the other. About 7 or 8 miles round trip.
> >
> > He cycles occasionaly, but finds it a bit much to do every day
> > because
> > of the steep climb in both directions. I suggested an electric
> > bike,
>
> [snip]
>
> Perhaps a question to ask before pursuing the electric route, is how
> low is the lowest gear on the bike he has now? Admittedly the
> Malverns are steep, but with a 19" gear they might be rideable, even
> if only at 2 mph
>
> Jeremy Parker

not a bad idea, my old mountain bike's lowest is 19" which means that
you will get up the hill, how ever slowly. or not as case maybe.

roger
--
www.rogermerriman.com

[Roger Merriman]

Paul Murphy > wrote:

> "Roger Merriman" > wrote in message
> ...
> > Paul Murphy > wrote:
> >
> >> The geared hub motor is a bit like having a car with only one gear - it's
> >> still a compromise gear ratio that should cope with scenarios the
> >> designer
> >> incorporates into the bikes performance envelope. Even with a single
> >> geared
> >> hub and adding electronic motor switching as mentioned by Allan, the
> >> outcome
> >> is still nowhere near as flexible as simply having your motor running at
> >> it's most efficient speed almost all the time like with a car, by
> >> changing
> >> the gears to suit the terrain. When you look at all the electric assist
> >> bikes that are the prestigious models (eg Swizzbee, Optibike, Swiss
> >> Flyer -
> >> with prices to match), they all incorporate crank drive/motor power
> >> through
> >> the gears designs rather than hub motors.
> >>
> >> Paul
> >
> > well no electric motors have a much broader range of operation, they can
> > operatate at zero or even - revs, thus having a number of gears like in
> > a car isn't needed as much.
>
> Not needed as much but if you want top efficiency under varied terrain,
> still the best bet. Anything else is a compromise. A single gear motor bike
> may be a closer match. Although there are electric motorbikes without gears
> (those mentioned were at the recent New Forrest electric bike rally a few
> months ago), These weigh ALOT more than electric bicycles and have massive
> heavy high capacity batteries and motors rated at several kilowatts power
> output, efficiency isn't so crucial for these machines.
>
> Paul

gears will upto a point give better efficency but thats not the same as
needed. a single gear motorbike at least a ICE one will suffer from the
range of workable revs, while the eleectric one can be done.

roger
--
www.rogermerriman.com

[James Thomson]

"Jeremy Parker" > a écrit:

> Perhaps a question to ask before pursuing the electric route, is
> how low is the lowest gear on the bike he has now? Admittedly
> the Malverns are steep, but with a 19" gear they might be rideable,
> even if only at 2 mph

Similarly, is there a longer, flatter route?

James Thomson

[Alan Braggins]

In article >, Paul Murphy wrote:
>"Rob Morley" > wrote in message
t...
>
>> Electric trains don't have gears, despite that fact that they need to
>> produce very high starting torque and also push out high power while
>> running efficiently at higher speeds.
>
>I think a huge difference is the fact they have a permanent power supply and
>aren't limited to 250 Watts maximum motor power output (thats one limitation
>for electric bikes in the EU).

Nitpicking, that's 250W maximum _continuous_ motor power output (and
200W for most bikes). A motor which briefly produces more than that
while starting is legal, but that won't help with prolonged hill
climbing.

[Alan Braggins]

In article >, Roger Merriman wrote:
>>
>> Not needed as much but if you want top efficiency under varied terrain,
>> still the best bet.
>
>gears will upto a point give better efficency but thats not the same as
>needed.

No more than gears are _needed_ for a purely human powered bike.
But there's a reason most mountain bikes have multiple gears even
though humans are also more flexible than ICEs and can produce high
torque when stalled - and anyone who puts a higher priority on the
elegant simplicity of a single speed mountain bike isn't going to
want an electric assist if they can avoid it.

[Paul Murphy]

"Alan Braggins" > wrote in message
...
> In article >, Paul Murphy wrote:
>>"Rob Morley" > wrote in message
t...
>>
>>> Electric trains don't have gears, despite that fact that they need to
>>> produce very high starting torque and also push out high power while
>>> running efficiently at higher speeds.
>>
>>I think a huge difference is the fact they have a permanent power supply
>>and
>>aren't limited to 250 Watts maximum motor power output (thats one
>>limitation
>>for electric bikes in the EU).
>
> Nitpicking, that's 250W maximum _continuous_ motor power output (and
> 200W for most bikes). A motor which briefly produces more than that
> while starting is legal, but that won't help with prolonged hill
> climbing.

The 200 Watt limit is in the UK and not EU wide. On that point though my
Giant Twist motor is officially rated at 240 Watts and that bike was
purchased legally in the UK. Given the performance and speeds I've seen out
of some electric bikes sold here I imagine these things aren't a priority
for those responsible for enforcement.

[Alan Braggins]

In article >, Paul Murphy wrote:
>"Alan Braggins" > wrote in message
>>
>> Nitpicking, that's 250W maximum _continuous_ motor power output (and
>> 200W for most bikes). A motor which briefly produces more than that
>> while starting is legal, but that won't help with prolonged hill
>> climbing.
>
>The 200 Watt limit is in the UK and not EU wide.

Yes, but this is UK.rec.cycling. The 250W EU limit allows it to be sold
without type approval, not necessarily to count as an EAPC.


> On that point though my
>Giant Twist motor is officially rated at 240 Watts and that bike was
>purchased legally in the UK.

There are lots of vehicles which can be legally purchased but not
legally used on the road (and others that can be legally purchased but
not used on the road without registration and insurance).


> Given the performance and speeds I've seen out
>of some electric bikes sold here I imagine these things aren't a priority
>for those responsible for enforcement.

That's a different argument. I see plenty of cars exceeding 70mph on
motorways and dual carriageways, but that's still the legal speed limit.

[Paul Murphy]

"Alan Braggins" > wrote in message
...
> In article >, Paul Murphy wrote:
>>The 200 Watt limit is in the UK and not EU wide.
>
> Yes, but this is UK.rec.cycling. The 250W EU limit allows it to be sold
> without type approval, not necessarily to count as an EAPC.

Similarly the 200 Watt limit here is not the be all and end all, lots of
other things such as weight limits must be complied with. There are some
electric bikes allowed 250 Watts here - I've heard tricycles qualify. I used
the EU limit (and clearly stated that) because that appears to be most
widely accepted and its the UK which is out on a limb with only 200 Watts
for 2 wheel bikes.

>> On that point though my Giant Twist motor is officially rated at 240
>> Watts and that bike was purchased legally in the UK.

> There are lots of vehicles which can be legally purchased but not
> legally used on the road (and others that can be legally purchased but
> not used on the road without registration and insurance).

The fact trading standards aren't clamping down on (as just one example) the
sale of electric bikes which operate without the need to pedal, tells me
they're not being pedantic and they recognise other issues deserve higher
priority.

>> Given the performance and speeds I've seen out of some electric bikes
>> sold here I imagine these things aren't a priority for those responsible
>> for enforcement.

> That's a different argument. I see plenty of cars exceeding 70mph on
> motorways and dual carriageways, but that's still the legal speed limit.

Cars in the UK aren't required by law to have a 70 mph max speed under power
but electric assisted bikes are limited to 15 mph under power according to
the law here (again other countries are more lenient and the USA (generally)
allows 20 mph and much more power than here too).

[Alan Braggins]

In article >, Paul Murphy wrote:
>
>Similarly the 200 Watt limit here is not the be all and end all, lots of
>other things such as weight limits must be complied with. There are some
>electric bikes allowed 250 Watts here - I've heard tricycles qualify.

And tandems, which is why I said "for most bikes", not "for bikes".


>>> Given the performance and speeds I've seen out of some electric bikes
>>> sold here I imagine these things aren't a priority for those responsible
>>> for enforcement.
>
>> That's a different argument. I see plenty of cars exceeding 70mph on
>> motorways and dual carriageways, but that's still the legal speed limit.
>
>Cars in the UK aren't required by law to have a 70 mph max speed under power
>but electric assisted bikes are limited to 15 mph under power

http://www.chambersharrap.co.uk/chambers/features/chref/chref.py/main?query=analogy&title=21st
HTH.

[Paul Murphy]

"Alan Braggins" > wrote in message
...
> In article >, Paul Murphy wrote:
>>
>>Similarly the 200 Watt limit here is not the be all and end all, lots of
>>other things such as weight limits must be complied with. There are some
>>electric bikes allowed 250 Watts here - I've heard tricycles qualify.
>
> And tandems, which is why I said "for most bikes", not "for bikes".

Yes, they're also allowed to be heavier than single seat bikes under the
power assisted bicycle regs.

>>>> Given the performance and speeds I've seen out of some electric bikes
>>>> sold here I imagine these things aren't a priority for those
>>>> responsible
>>>> for enforcement.
>>
>>> That's a different argument. I see plenty of cars exceeding 70mph on
>>> motorways and dual carriageways, but that's still the legal speed limit.
>>
>>Cars in the UK aren't required by law to have a 70 mph max speed under
>>power
>>but electric assisted bikes are limited to 15 mph under power
>
> http://www.chambersharrap.co.uk/chambers/features/chref/chref.py/main?query=analogy&title=21st
> HTH.

Perhaps I didn't make it clear enough. Cars sold in the UK can be capable of
exceeding 70 mph, it's just that to use them above 70 mph is not legal on
our public highways. Electric bikes on the other hand, in order to comply
with UK regs must not be capable of exceeding 15 mph under power. You can
pedal them faster than this or go faster downhill etc but the motor must not
be assisting at speeds above 15 mph. :-)

Paul

[Roger Merriman]

Paul Murphy > wrote:

> "Bob" > wrote in message
> ps.com...
> > If anyone has any experience of using an electric bike in a hilly
> > area, please let me know what model it was and how effective it was
> > (and how steep the hills were).
>
> As suggested already a system where the motor power goes through the gears
> is your friends best bet. I have a 2006 Giant Twist (formerly known as the
> LaFree) Comfort with 5 speed gears and have yet to encounter a hill which it
> cant get up. I don't know how to find gradients on line but if you know the
> hill up to Downley in High Wycombe (it's called The Pastures), my bike gets
> up that and other hills such as Marlow Hill, Hedsor Hill and Whitepit Lane
> with no problem and that's with a rider over 100 kg and a full pannier bag
> up The Pastures and Marlow Hill. It was quite slow but still much faster
> than getting off and pushing (which is what many other cyclists I see tend
> to do)!
>
having a flick though maps (can't beat a map!) the first climb up from
the A40/railwayline up is 1 in 5 or 20% so reasonbly steep yes.

> Be aware that the current Giant Twist models have sacrificed the motor drive
> through the gears system in favour of a cheaper less flexible hub motor
> design and has not received the same great reviews as the older models.
> Aside from the mentioned Gazelle Easy Glider, there are other new bikes such
> as the Swiss Flyer range and Swizzbee which use motor power through the
> gears but these cost even more, they are top quality bikes though.
>
> Paul

roger
--
www.rogermerriman.com

[Paul Murphy]

"Roger Merriman" > wrote in message
. uk...
> Paul Murphy > wrote:
>
>> "Bob" > wrote in message
>> ps.com...
>> > If anyone has any experience of using an electric bike in a hilly
>> > area, please let me know what model it was and how effective it was
>> > (and how steep the hills were).
>>
>> As suggested already a system where the motor power goes through the
>> gears
>> is your friends best bet. I have a 2006 Giant Twist (formerly known as
>> the
>> LaFree) Comfort with 5 speed gears and have yet to encounter a hill which
>> it
>> cant get up. I don't know how to find gradients on line but if you know
>> the
>> hill up to Downley in High Wycombe (it's called The Pastures), my bike
>> gets
>> up that and other hills such as Marlow Hill, Hedsor Hill and Whitepit
>> Lane
>> with no problem and that's with a rider over 100 kg and a full pannier
>> bag
>> up The Pastures and Marlow Hill. It was quite slow but still much faster
>> than getting off and pushing (which is what many other cyclists I see
>> tend
>> to do)!
>>
> having a flick though maps (can't beat a map!) the first climb up from
> the A40/railwayline up is 1 in 5 or 20% so reasonbly steep yes.

So thats what a 1 in 5 hill looks like then, thanks for that info. I've
contacted OS about how I can find gradient info online and have received a
card through the post advising they'll reply soon. Unfortunately my new GPS
equipped phone doesn't seem to do gradients (although the rest is great).

Paul

[DavidR[_2_]]

"Alan Braggins" > wrote
>
> No, in particular many have maximum torque when stalled,

Maximum torque is still a maximum. The point of gearing is to alter that
value at the point of delivery.

Is a small motor with gearbox better or worse for size/weight/expense than
a bigger motor?

[Roger Merriman]

DavidR > wrote:

> "Alan Braggins" > wrote
> >
> > No, in particular many have maximum torque when stalled,
>
> Maximum torque is still a maximum. The point of gearing is to alter that
> value at the point of delivery.
>
> Is a small motor with gearbox better or worse for size/weight/expense than
> a bigger motor?

in the uk there is legal limit, on the power, so all things being equal
a gearbox is better,

as to if it's needed well thats another point, i have seen electric
bikes around here, (kingston upon thames) which is fairly flat area so
even the weediest electric bike should be fine.

roger
--
www.rogermerriman.com