Before you buy a new electric bike-some important considerations

Eagle

Esteemed Pedelecer
Aug 31, 2012
381
134
I have learned a great deal on these invaluable Pedelecs forums in a very short time from the many knowledgeable contributors who know a lot more about electrical bikes than me. I am extremely grateful to all those who have helped me and I would now like to return the favour for those planning to purchase an electric bike.

I realise that a lot of this has been covered previously, but I can tell from the forums that there still seems to be considerable confusion in the minds of some potential electric bike purchasers as to what exactly they should look out for in a new machine.
I hope that they find this post useful.

For the purposes of this thread I am going to take a closer look at my own bikes, the Tonaro Bighit (crank-driven) and the FreeGo Eagle (hub-driven).

They are both superb electric bikes and they both perform brilliantly. They just happen to behave differently, that's all.

Firstly, the key issues for a new buyer to consider are:
1) Your personal level of fitness and general health.
2) The type of terrain on which you are mostly going to ride the bike and the speeds at which you are most likely to travel.
3) What specifically you want the bike to be able to do for YOU.

I would like to try and clarify, in broad terms only, the main differences between crank-driven and hub-driven machines.
It is a very important consideration and a great deal depends on the purchaser's individual circumstances and requirements.

Crank-driven versus hub-driven
Generally speaking, a crank-driven bike is better for going up steep hills. A hub-driven bike can usually only manage less steep hills.
This is because the maximum torque (twisting/turning effect/amount of rotational force) generated by the crank-driven Tonaro Bighit is more than twice that of the hub-driven motor on the FreeGo Eagle.

The reason for this is that the Tonaro's torque is being applied (via the bottom bracket) to the FRONT chainwheel and therefore the actual amount of torque transmitted to the REAR hub (via the chain) is geared up significantly.
In contrast, the FreeGo Eagle's hub-driven motor applies its torque directly to the rear hub and therefore there is no gearing effect.

Having said that, I cannot honestly say that I can presently find a huge difference between the climbing abilities of the two bikes. I probably just need to get a lot fitter!

A really important difference to note is that, in many ways the Tonaro Bighit behaves much more like a normal push bike than the FreeGo Eagle, as you will see from the following.

Riding on the flat
When ALL legal electric bikes reach 15 mph, the power is automatically switched off because of the restriction imposed by law (UK and/or EU, who knows? In any case, that is a totally separate subject).
On the flat with the hub-driven FreeGo Eagle, this means as soon as you exceed 15 mph, you then begin pedalling at fresh air, until your speed once again drops below 15 mph.

With the crank-driven Tonaro Bighit, the power is also cut at 15 mph, BUT, if you wish and you are strong enough, you can still continue to ride the bike in the same way as an ordinary, push bike.
This means that you can ride (quite legally, in case anybody asks) above 15 mph, if you wish, whilst NOT using battery power and thus effectively increasing the battery's range.

There is yet another point to consider on the flat and that is when travelling below 15 mph.
Since pedalling is generally much easier on the flat, you may decide to conserve your battery and reduce the amount of powered assistance or switch off the power completely.

With a crank-driven bike like the Tonaro Bighit, this is no problem. When the power is switched OFF, there is no additional resistance when pedalling the bike (because the motor uses a clutch) and it can be ridden in exactly the same way as a normal push bike.

With a hub-driven bike like the FreeGo Eagle, there is a problem when the power is OFF because of the high resistance or drag from the hub motor. Imagine yourself trying to cycle through very deep porridge or treacle!

Other things I have noticed on the two bikes

Saddle: As original equipment (OEM) the Eagle has a super-comfy, well-padded gel saddle, which I am sure is a Specialized Expedition Gel Saddle (currently £24.99 including postage from Evans Cycles):
Specialized Expedition Gel Saddle | Evans Cycles
I bought this to replace the Bighit's original saddle, which is hard and unyielding, even with my extra padding in that area! Most Bighit owners seem to replace the OEM saddle.

Rear suspension: No contest whatsoever! The Bighit gives a fabulous magic carpet ride, even over the roughest surfaces. No “hardtail” bike like the Eagle can compete with it.

Gear change/shifters: The Eagle's thumb shift for going UP the gears is superb. I much prefer it to the Bighit's double lever type. This is just a matter of personal preference. The latter works fine.
The Eagle displays every single gear but the Bighit only displays numbers 1 and 8.

Throttles: Both bikes have throttles.

Battery range: Too early for me to tell. However, if you travel mainly on the flat, then the Bighit, unlike the Eagle, will allow you to pedal normally with the power off and thus extend the battery's range.

Build quality: Both bikes seem to be well put together and use decent quality components.

Price: The Tonaro Bighit is £1200 and the FreeGo Eagle is £1299 with the 36v/10ah battery (£200 extra for the 36v/17ah battery)
I should also point out to prospective purchasers that the Tonaro Bighit is HALF the price of its major crank-driven competitors.

For further information visit:
FreeGo:
Electric Bikes For Sale, Ebikes and Battery powered Bikes from FreeGo Electric Bikes

Tonaro (Powerpedals):
Home Page of Powerpedals electric bicycles
 

scarrabri

Pedelecer
May 14, 2011
248
4
Stoke on Trent
I have learned a great deal on these invaluable Pedelecs forums in a very short time from the many knowledgeable contributors who know a lot more about electrical bikes than me. I am extremely grateful to all those who have helped me and I would now like to return the favour for those planning to purchase an electric bike.

I realise that a lot of this has been covered previously, but I can tell from the forums that there still seems to be considerable confusion in the minds of some potential electric bike purchasers as to what exactly they should look out for in a new machine.
I hope that they find this post useful.

For the purposes of this thread I am going to take a closer look at my own bikes, the Tonaro Bighit (crank-driven) and the FreeGo Eagle (hub-driven).

They are both superb electric bikes and they both perform brilliantly. They just happen to behave differently, that's all.

Firstly, the key issues for a new buyer to consider are:
1) Your personal level of fitness and general health.
2) The type of terrain on which you are mostly going to ride the bike and the speeds at which you are most likely to travel.
3) What specifically you want the bike to be able to do for YOU.

I would like to try and clarify, in broad terms only, the main differences between crank-driven and hub-driven machines.
It is a very important consideration and a great deal depends on the purchaser's individual circumstances and requirements.

Crank-driven versus hub-driven
Generally speaking, a crank-driven bike is better for going up steep hills. A hub-driven bike can usually only manage less steep hills.
This is because the maximum torque (twisting/turning effect/amount of rotational force) generated by the crank-driven Tonaro Bighit is more than twice that of the hub-driven motor on the FreeGo Eagle.

The reason for this is that the Tonaro's torque is being applied (via the bottom bracket) to the FRONT chainwheel and therefore the actual amount of torque transmitted to the REAR hub (via the chain) is geared up significantly.
In contrast, the FreeGo Eagle's hub-driven motor applies its torque directly to the rear hub and therefore there is no gearing effect.

Having said that, I cannot honestly say that I can presently find a huge difference between the climbing abilities of the two bikes. I probably just need to get a lot fitter!

A really important difference to note is that, in many ways the Tonaro Bighit behaves much more like a normal push bike than the FreeGo Eagle, as you will see from the following.

Riding on the flat
When ALL legal electric bikes reach 15 mph, the power is automatically switched off because of the restriction imposed by law (UK and/or EU, who knows? In any case, that is a totally separate subject).
On the flat with the hub-driven FreeGo Eagle, this means as soon as you exceed 15 mph, you then begin pedalling at fresh air, until your speed once again drops below 15 mph.

With the crank-driven Tonaro Bighit, the power is also cut at 15 mph, BUT, if you wish and you are strong enough, you can still continue to ride the bike in the same way as an ordinary, push bike.
This means that you can ride (quite legally, in case anybody asks) above 15 mph, if you wish, whilst NOT using battery power and thus effectively increasing the battery's range.

There is yet another point to consider on the flat and that is when travelling below 15 mph.
Since pedalling is generally much easier on the flat, you may decide to conserve your battery and reduce the amount of powered assistance or switch off the power completely.

With a crank-driven bike like the Tonaro Bighit, this is no problem. When the power is switched OFF, there is no additional resistance when pedalling the bike (because the motor uses a clutch) and it can be ridden in exactly the same way as a normal push bike.

With a hub-driven bike like the FreeGo Eagle, there is a problem when the power is OFF because of the high resistance or drag from the hub motor. Imagine yourself trying to cycle through very deep porridge or treacle!

Other things I have noticed on the two bikes

Saddle: As original equipment (OEM) the Eagle has a super-comfy, well-padded gel saddle, which I am sure is a Specialized Expedition Gel Saddle (currently £24.99 including postage from Evans Cycles):
Specialized Expedition Gel Saddle | Evans Cycles
I bought this to replace the Bighit's original saddle, which is hard and unyielding, even with my extra padding in that area! Most Bighit owners seem to replace the OEM saddle.

Rear suspension: No contest whatsoever! The Bighit gives a fabulous magic carpet ride, even over the roughest surfaces. No “hardtail” bike like the Eagle can compete with it.

Gear change/shifters: The Eagle's thumb shift for going UP the gears is superb. I much prefer it to the Bighit's double lever type. This is just a matter of personal preference. The latter works fine.
The Eagle displays every single gear but the Bighit only displays numbers 1 and 8.

Throttles: Both bikes have throttles.

Battery range: Too early for me to tell. However, if you travel mainly on the flat, then the Bighit, unlike the Eagle, will allow you to pedal normally with the power off and thus extend the battery's range.

Build quality: Both bikes seem to be well put together and use decent quality components.

Price: The Tonaro Bighit is £1200 and the FreeGo Eagle is £1299 with the 36v/10ah battery (£200 extra for the 36v/17ah battery)
I should also point out to prospective purchasers that the Tonaro Bighit is HALF the price of its major crank-driven competitors.

For further information visit:
FreeGo:
Electric Bikes For Sale, Ebikes and Battery powered Bikes from FreeGo Electric Bikes

Tonaro (Powerpedals):
Home Page of Powerpedals electric bicycles
Hi really like this read up and it shows a fair indication of of what you have in the Bighit E/Bike and as i have rode one for a couple of years this certainly sums it up and has provided me with many happy rides and trouble free adventures and i am very pleased with it ,i have never rode an Eagle but this again sounds a fine E/Bike .
 

Kudoscycles

Official Trade Member
Apr 15, 2011
5,566
5,048
www.kudoscycles.com
Useful review of the Bighit from New Zealand.


Review of the standard bike.
The Tonaro Big hit is available in New Zealand for about $2000. One of the lower priced e bikes on the market.
The model purchased is the lowest spec in regards to componentry, suspension and gears. In Europe they produce much higher spec bikes. They claim the 200w mid drive motor to perform the same as a 500w hub motor. Hmmm.

First ride impressions.
The bike is set up with pedal assist. You have to pedal for the motor to cut in. Not good. Any mountain bike that has this already shoots its self in the foot. You need the motor to get started on a hill, and the fact that it take 2 pedal revolutions before it cuts in means you often find your self stalling and rolling backwards before the motor provides any assistance.
However, once the motor does cut in, its all on. One speed, full throttle. In low gear, the bike climbs superbly with no effort from you. A definite advantage over hub drive motors. For slow speed mountain trails with steep climbs, a mid drive geared system is the way to go. After 2nd gear however, I see no real advantage over the hub motor in performance.

Another big downfall of the pedal assist set up, is because the bike is always full throttle, you are making full throttle gear changes. SLAM!, SLAM!, SLAM! go the gears as you shift through them. Bike clusters were not designed for this. Any review that says the gear changing is smooth is rubbish. Other models of this bike use the Rolloff internal gear hub, that would be many times a better set up than a cluster. A fix to this issue is to fit a hand throttle, which we do in our upgrades.

The motor and gearbox appear of good design and robustness. The motor is very smooth and basically silent once at speed.



The controller is a tiny little 6fet controller, 15amp, with 50v capacitors, so limited to 36v batteries. It is possible to use a throttle with this controller. You could also up the current to 20amps and be ok.

The bike tops out at 32km/h with the restrictor removed on the stock 36v battery.

The battery is a Lithium Ion prismatic cell 10ah. It is a low cost, mid performance battery. Very light, but has considerable voltage sag and I would not expect more than about 500 recharges before the performance was unbearable. However, it works well for this low power set up.

The bike frame is Aluminium, and very basic. Reasonably good style frame but lacks any production finesse. No progressive linkages and the rear shock, is a shock absorber, rather than suspension. The front shocks are your low cost rock shocks, that work ok with various adjustments and fine for light off road use.

I think the term, light off-road use is appropriate for this bike. Trail riding, smooth tracks and 2″ high jumps.

As a stock bike, the performance is usable and the bike would make a great weekend electric bike, or road commuter. An upgrade to a hand throttle and immediate start, rather than pedal start would make the world of difference to the usability of this bike.

EVLAB upgrades.

The 3 core upgrades asked for to make this bike perform much better were, immediate start throttle, the ability to run a 48v battery, and cycle analyst computer.

We set out by removing the stock interface, pedal assist sensor, controller, basically everything but the motor.
I retained the wiring harness that goes through the frame, though put new plugs on it. Be aware, the colours going in on end are not necessarily the same colours coming out the other! The stock wiring of this bike was poor, with many wires pulling out of there crimps with little force.



A new infineon 48v 25amp controller was fitted with cruise control. A thumb throttle was fitted along with a large screen cycle analyst. Also we have fitted a temperature monitor to the motor to see how well it handles 48v.










The bike is a million times better with the thumb throttle. You can now start half way up a slope, hit the throttle and off you go. With the 48v battery the bike will pull a wheelie, how ever that is over pretty quick as the motor reaches its top speed in a second. Now with the throttle you can let the power off and make smooth motorcycle style gear changes.

Top speed with the 48v battery was 40km/h. The bike was climbing most hills on the road at about 30km/h, step hills at 20km/h. I rode up a track in the bush that all my hub motors stall and this kept going until I lost traction. At 48v I think it would climb almost anything, though 30 seconds full power climbing will get the motor quite hot.

On the standard 36v pack, now running more amps, I can manage to get the motor to stall going up the bush track.

In summary, at 48v about 20amps, this bike comes alive. The performance becomes usable and fun.
However, this bike, even with the upgrades has not won me over hub motors. I would still choose a Nine Continent 2808 at 48v 25amps for the sheer smoothness and acceleration. But for tight track work and slower riding, this bike would be great and will still be going up when the hub motors had stalled out.

Recommendation.
Buy as a light use trail bike or commuter. Make the modification to hand throttle. Enjoy.










7 comments



joma / November 6, 2011


Hi NZ biker ,

Your test is nice. In France this bike is called Bigith 4, and it is very similar. Tested at greater length with 48 volts? Did the problems of heating of the engine they appear you too strong? Lastly, my question, with a controller in 36 volts from 400 / 500 Watts: It’s possible to have more power at low speed and especially without overheating the engine?
Ideas ? Some links ?

Thank U for your feedback and bon voyage.





Cliff Randall / November 17, 2011


Hi Joma

So far I am having no problem running the motor on 48V but I am careful to keep the current below 15 amp, I can pull 25 amps. I use the cycleanalyst like an electrical tachnometer using the measured current to select the appropriate gear. Dropping down one gear can lower the current by 20 to 40% for a 10% drop in speed. Next week I am replacing the deraileur gear system with a 14 gear Rohloff internal hub which will give me a lot more control over current pull and reduce the risk of overheating. Also the Rohloff with a higher top gear means I could do 45-50 km/hr on the flat!

Cliff





Anthony Brooker / December 4, 2011


Great review, I was thinking of doing this for a while now as these bikes have been starting to become available as second hand (used)bikes. I have heard the frames are heavy also, so if you need to replace almost everything I am torn between this or just starting from a good mountain bike and kit. Have you seen the Torneo crank motor kit? This would be a way of building a usable bike without paying for bits that you are going to not use. Well done again
 
Last edited:

Geebee

Esteemed Pedelecer
Mar 26, 2010
1,256
227
Australia
Eagle, your limited exposure to hub motors has made your statements regarding Hubs incorrect, a geared hub motor will have hardly any drag and riding such a bike is little different to riding any un-powered bike of the same weight.
Also there is no reason other than too low a gearing that you can't pedal a hub motor well beyond the assisted speed, it just means you are doing the work not the motor, just like the crank drive.
 

Eagle

Esteemed Pedelecer
Aug 31, 2012
381
134
Geebee,
I can only speak about my own experiences on my FreeGo Eagle.
On the flat the drag is very noticeable, compared to nil resistance with the Bighit.

However, going down a slight incline with the Eagle overcomes this drag and it then becomes hardly noticeable.
 

gray198

Esteemed Pedelecer
Apr 4, 2012
1,578
1,069
I would second that Eagle. The Freego Eagle is a great bike, but there is definitely a feeling of drag or heaviness at the back end when pedalling without power. I thought this may be just down to me being unfit and really have nothing to compare to, but all the same with the power on it is really good

gray

Ps I wonder if the drag factor gets less the more it is used
 

Eagle

Esteemed Pedelecer
Aug 31, 2012
381
134
gray198,
Thanks for confirming that it was not a figment of my imagination about the motor drag on the Eagle.
I somehow doubt whether the drag will lessen with use but I could be wrong.
 

flecc

Member
Oct 25, 2006
52,790
30,369
As has often been posted previously, in theory there should be no drag on these freewheeled internally geared motors. However, in practice it's a sad fact that many of them do exhibit very noticeable drag when unpowered under normal riding conditions. I proved this on one occasion by swapping out a hub motor front wheel for a normal bike one for a test ride, and it transformed the bike (Torq 1) from very sluggish to pedal above about 12 mph with motor to a perfectly acceptable bike without.

The crank drive bikes always win out in this respect, being little different to pedal from any normal bike
 
D

Deleted member 4366

Guest
A bafang hub-motor should spin like these. If it doesn't, there's something wrong: clutch stuck, brakes binding, etc. Whenever someone mentions hub-motor drag, we never get the results of this simple test, which will show whether there is or isn't drag.

The first one is mine - now on Saneagle's bike. The second is a German one spun in reverse first to show the difference.
Bafang - YouTube
Bafang - FREILAUFEIGENSCHAFTEN - Nabenmotor - YouTube
 

Eagle

Esteemed Pedelecer
Aug 31, 2012
381
134
d8veh,
You are correct as usual!
After watching the two videos I gave the rear wheel a spin and discovered a binding rear brake.
I slackened it off and all is now well. Sorry about the misinformation.
I will double-check this "hub drag" with a ride tomorrow.

gray198,
You had better check that your rear wheel spins easily as per the videos.
 

Eaglerider

Esteemed Pedelecer
Oct 25, 2011
370
47
East Sussex
I too have noticed the apparent drag when I switch the power off.

I have come to the conclusion that it is largely just my perception of the sudden loss of assistance.

If I start a ride without power, starting in first gear, it seems fine. A heavy bike for sure, but bearing in mind first gear is quite high compared to first gear on my unassisted mountain bike, its not too bad.

If I spin the rear wheel, it continues for ages, so there is no drag at all from the freewheel. I think, when you cut power, the clutch doesn't disengage immediately which provides a moment of feeling like the brakes are on. If I stop and then set off again, the drag seems to disappear.

In order to resolve this, I went out on my 11Kg Raleigh M-Trax, and in fact, because the gear range is much greater, I didn't perceive it as being any slower. It is half the weight of my Eagle, so it would feel a little nippier, but I found I was cycling only one or two mph slower power off on the Eagle than I did on the Raleigh. As such, I don't think there is any motor drag of significance, but the sudden shock of losing the power just goes to show how much assistance you have been getting.

A while back I had a ride on a very old 'Henderson' bicycle. It weighed a ton, and felt like riding through treacle.
Accordingly, I would suggest that the 'drag' sensation is merely a perception of pedalling all that weight along with just your legs, after having just had all that 'help' when the power was on.

The Tektro brakes are quite good, but do require regular fettling to prevent them from sticking and squeeking!

On the other hand, on full power, its wonderful!
 
Last edited:

Eagle

Esteemed Pedelecer
Aug 31, 2012
381
134
a geared hub motor will have hardly any drag and riding such a bike is little different to riding any un-powered bike of the same weight.
Geebee,

You are correct, my apologies to one and all for the misinformation.

I am afraid that it was that well known Law of S** intervening via a binding rear brake and confusing the hub drag issue.

Is it possible to edit my original post? I cannot see an edit button for it, presumably because it is too old.

Can the admins do anything to fix this?
 
Last edited: