My wife is getting rid of her car through a car scrappage scheme. The scheme will give her £2000 in vouchers to spend on ebikes but only a specific shops. The options are quite limited and include Halfords. Can anyone tell me if Halfords sell any decent ebikes? I have a cube tourer 400 and would like it to be of a similar ish quality if possible.
Halford's ebikes
- Thread starter Skyb87
- Start date
I have attempted to illustrate real world achieved efficiency rather than bench test maximum efficiency, because that is what matters to the rider.
You are right that bench test best is indeed a direct drive hub motor, but on a long Scottish ascent with touring weight and only 250W plus limited stretching of that on hills to remain UK legal, they are in fact the worst choice. Have a look at the efficiency in the simulator at 4mph: 10% if you are lucky!
To stay at an efficient speed on such a hill, such a motor requires upwards of a kW of power, which we are not allowed in the UK. So bench test says one thing, real world says another.
There a great video that came out today but Grin actually focused on regen but has a mid-drive vs direct drive comparison regarding efficiency about 37 minutes in. It basically shows that a direct drive motor can be more efficient in real world conditions plus you have the greater reliability of the direct drive motor, plus you have the massive reduction in drivetrain wear, plus you have the reduced wear to brakes due to regen braking so the overall costs of running a direct drive motor are massively lower than mid-drive and a far more dependable system. However again I'm stating the superiority of direct drive over mid-drive as a road vehicle no question mid-drive is a better system for e-mountain bikes which should be a scenario where the reduced reliability and reduce lifespan of drivetrain components is not such an issue as off-road tends to be more of a weekend pursuit. Also for very weak frail cyclists the fact hill climbing ability is stronger could be critical to them so for such cyclists on the road again mid-drive may have a greater advantage.
All configurations have their reasonable operating envelope, and riders have their local terrain and more distant aspirations to consider. The overlap of those two things shows what suits.
Direct drive is great for higher power, smaller wheels and flatter terrain. Not so good for 250W, 700c and hills.
It would be interesting to see comparative running costs of mid-drive drive train and relatively gentle battery use vs absolute hammering of battery for powerful hub drives with much lower drive train wear!
It might be worth asking if you can use the voucher with Tredz who are owned by Halfords and often are included in Cycle to Works schemes where Halfords are the preferred supplier. Tredz offer a much wider range of bikes than Halfords and seem to be their higher level shop.
As that video shows by its example of efficiency while direct drive motors don't reach mid-drive motors for efficiency on steep hills they are perhaps around 20% apart in efficiency for very steep hills and marginal difference in efficiency for lighter more normal hills and their efficiency climbs with heavier loads. 65% efficiency at 400 watts with the rider making more effort themselves is still less power drawn than someone using 700 watts at 80% efficiency who goes up the hill faster with less effort themselves. Also regen can recoup a chunk of energy which again varies but ranges from about 2-15% based on conditions and a heavier rider will find it easier to recoup energy as it will be easier for them.
Admittedly this engineer is biased in favour of trying to make the most reliable ebike an almost maintenance free ebike and of course that has to be direct drive so that is what he uses. However in contrast much of the cycling media is trying to promote mid-drive ebikes which are the most expensive option producing the most profit for them so you get a huge amount of nonsense promoting mid-drive that makes very little sense with regard efficiency, reliability, drivetrain wear etc. So much false information is given by the media making many false negative claims about hub motors and false positive claims about mid-drive.
Like the video here that shows a heavily used 10 year old hub motor getting restored to working condition for the price of a few bearings and not much else. In that time it would likely have massively extended the life of the drivetrain saving a huge amount of money and if regen is enabled saved a huge amount of money on the brake system too and once serviced is probably good for another 10 years.
I feel strongly that direct drive is so superior to mid-drive for long term commuting or touring ebikes on so many levels compared to proprietary high cost mid-drive motors which personally I think are garbage and overall over the long term have very low efficiency and value.
Show me a 250W nominal direct drive hub motor climbing a long 1 in 10 hill at touring weight and achieving 65% efficiency and I might start to take notice!
Ok I've tried to simulate 250W from a typical direct drive motor on the chart. If you look at the red line you see the power is about 250W-400W which I would say is typical for such a motor with 400W being peak, they don't peak anywhere as much as a mid-drive motor. You can also see the Newton metres peak at 38Nm which I would say again was typical for such a direct drive motor they don't go as high as fairly meaty mid-drive motor even 250W. You can also see the drop off at 25km per hour which again would be typical of such a motor. I've had to set the throttle to 60% in order to keep the watts as per a 250W configured motor as the original motor is more powerful. I've set the bike to the highest overall weight of 170kg which is the maximum setting unless you choose custom so a heavy ebike, heavy rider and a lot of touring luggage mounted. So as you can see from the chart at 8.8km per hour you start at about 44% efficiency and you peak at about 84% efficiency as you go faster so the average is about 64% efficiency. The issue is how much effort you put in, if you put in a bit more than 150W then speed and efficiency climbs but if you put less than 150W then efficiency and speed drops. However I have used an excessively loaded bike as the example at 120kg total load the average speed goes up significantly and the efficiency starts at 64% with this increased average speed. If you stay at 120kg total load and have a rider who can only produce 100W then the efficiency starts at 60%. There are no gear restrictions at all with a hub motor ebike so you could have a 3x11 setup if you wanted to to give you full control of your cadence and optimise your power levels in addition to the motor power. On very heavy ebike like that when you come down the hill you will get probably the full 15% regen so if the bike was expected to have assisted distance of 30 miles without regen you could get 34.5 miles. However the lighter the load of the bike the less the regen.
All-Axle Hub Motor - Grin Products - Product Info
The All Axle motor takes the simplicity and robustness of the direct drive hub motor, and optimizes it for the modern bike platform. This hub is fully compatible with all quick release and thru-axle bike forks, it is over 30% lighter than standard generic hubs of similar power (4kg vs 6kg), and...
You are more than welcome to make a comparison with a mid-drive motor the point I would raise is going up the hill would significantly add additional wear to your drivetrain components and going down the hill would significantly wear your brake pads and inside the mid-drive motor itself as you climb you would have continued to wear down the gearing significantly if a steep hill especially with a load of 170kg.
I appreciate the effort you are going to! I spent a fair time on the Grin Sim when deciding what the bike part of my solar plan would be, and for my requirements, which were influenced by the 1500km of long touring rides I did last year, and my plans for this year, I could not see a hub motor solution that worked, let alone a direct drive one.Ok I've tried to simulate 250W from a typical direct drive motor on the chart. If you look at the red line you see the power is about 250W-400W which I would say is typical for such a motor with 400W being peak, they don't peak anywhere as much as a mid-drive motor. You can also see the Newton metres peak at 38Nm which I would say again was typical for such a direct drive motor they don't go as high as fairly meaty mid-drive motor even 250W. You can also see the drop off at 25km per hour which again would be typical of such a motor. I've had to set the throttle to 60% in order to keep the watts as per a 250W configured motor as the original motor is more powerful. I've set the bike to the highest overall weight of 170kg which is the maximum setting unless you choose custom so a heavy ebike, heavy rider and a lot of touring luggage mounted. So as you can see from the chart at 8.8km per hour you start at about 44% efficiency and you peak at about 84% efficiency as you go faster so the average is about 64% efficiency. The issue is how much effort you put in, if you put in a bit more than 150W then speed and efficiency climbs but if you put less than 150W then efficiency and speed drops. However I have used an excessively loaded bike as the example at 120kg total load the average speed goes up significantly and the efficiency starts at 64% with this increased average speed. If you stay at 120kg total load and have a rider who can only produce 100W then the efficiency starts at 60%. There are no gear restrictions at all with a hub motor ebike so you could have a 3x11 setup if you wanted to to give you full control of your cadence and optimise your power levels in addition to the motor power. On very heavy ebike like that when you come down the hill you will get probably the full 15% regen so if the bike was expected to have assisted distance of 30 miles without regen you could get 34.5 miles. However the lighter the load of the bike the less the regen.
All-Axle Hub Motor - Grin Products - Product Info
The All Axle motor takes the simplicity and robustness of the direct drive hub motor, and optimizes it for the modern bike platform. This hub is fully compatible with all quick release and thru-axle bike forks, it is over 30% lighter than standard generic hubs of similar power (4kg vs 6kg), and...ebikes.ca
You are more than welcome to make a comparison with a mid-drive motor the point I would raise is going up the hill would significantly add additional wear to your drivetrain components and going down the hill would significantly wear your brake pads and inside the mid-drive motor itself as you climb you would have continued to wear down the gearing significantly if a steep hill especially with a load of 170kg.
View attachment 46169
My red lines are:
1. Properly UK pedelec rules compliant, not hiding lots of power behind a fake motor label. This gives some latitude, which I cap at short term power up to 500W, measured as electrical input not mechanical output. I have seen up to 470W on my Shimano, which makes me feel comfortable stretching it that far. I'm not willing to go to 750W or more.
2. Rider input constant, regardless of gradient, and limited to 100W. That is what I need, it will not be what everyone needs. As I mentioned some time ago, ebiking to me is biking with the hard work taken away. I don't mind going slowly up a hill, but I do mind working hard when I have a motor to do that for me!
3. Terrain: gradients of 1 in 5 must be possible albeit in bottom gear, without the need for rider effort to rise above 100W. This essentially means the bike can go up 1 in 5 without change in rider effort until the battery runs out, which it won't, because I'm towing a 330W solar trailer...
4. All up weight 125kg. That's bike, me, trailer, luggage.
I could not find any hub motor, geared or direct drive, on the sim that could meet my requirements, which is why I have a TSDZ2 sitting in a box for my old mountain bike, once I have finished learning about how to make a Shimano bike run on the sun!
I may be a special case for drivetrain wear too, as I am generally riding at human power of no more than 100W, and in lowest assistance level which is 140%, so my drivetrain is transmitting less than 240W. I have not gone looking for studies, but at a smidgen under 4,000km, 1400km of which has been in touring trim of 125kg or so, and 600km at an ill advised 150kg+, my first chain shows 1% stretch. I don't think that is too bad. Likewise, just about to replace brake pads for the first time.
The one thing I would like to have that the mid-drive cannot do is regen, and when I have time I may look into something like the Revos friction drive concept.
A lot has been said already, but I'll just add another little bit of 'from first principles' calculation:
At 250W motor output power plus 100W rider input, so 350W power, at 125kg mass so 1250N weight, rate of climb ignoring aero losses and rolling resistance is only 350 / 1250 = 0.28 vertical metres per second.
On my 1 in 5 requirement, that is a forward speed of 1.4m/s, or a tad over 3mph. That's the condition I would need a hub motor to manage. With a 700c wheel, that is about 38 rpm.
Yes there are lots of variables. A direct drive motor can be fully legal and you get pre-configured bikes with direct drive hubs that are legal. Remember its the controller that limits the power which for mid-drive is within the motor assembly I guess but for hub motors is normally external. It's weird legislation when almost all ebike motors on the UK market are above 250W but its the controllers where ever they are that restrict the power to somewhere close to 250W nominal or rated. Some of the highest power Bosch mid-drive motors will happily peak over 700W but I don't know about other mid-drive motors to be honest.
There isn't a legal issue with direct drive motors that are configured for 250W but visually they do look like they are more powerful but of course the reality is they are not when limited to 250-400W.
there is no power limit under 15.5mph my bosch bike has a 20amp controller that's on a pcb inside the motor so thats what gets you up the hills and eats the power doing it 
No one mentioned the boardman Fazua bikes Halfords do. I think the Hyb8.9e with discount may just come in under 2k. I have the adv 8.9e and it’s been a good bike so far.
the Fazua bikes are mid drive but light weight/minimal assistance. They can put out similar torque and power as the bigger Bosch motors but most of the time I keep mine on 100w to get a good range as the battery is smaller. The bike is 10kg lighter than the old Bosch powered tank I had.
the Fazua bikes are mid drive but light weight/minimal assistance. They can put out similar torque and power as the bigger Bosch motors but most of the time I keep mine on 100w to get a good range as the battery is smaller. The bike is 10kg lighter than the old Bosch powered tank I had.
I've read a few forum posts about Fazua motors which have reliability concerns. A recent thread is this one where the owner is looking to get a more reliable motor system.
Reliability of e-bike systems
I have used a variety of ebikes over the years for my 12 miles each way daily cycle commute in all weathers. All have proved variably unreliable with connection faults, battery issues and failed components. I now have a Fazua-equipped Focus Paralane which is great when it works but pretty often...
www.pedelecs.co.uk
However that said it sounds like he has gone through quite a few mid-drive motors so perhaps a particular powerful or heavy cyclist or maybe someone who does high number of miles.
Eddie pj only went out on his bike when it was pi$$ing down with rain and rode up and down bogs or rivers of mud.
now thats what he liked to do and in the 2 year warranty you will get the motor replaced no question if it is full of mud and did a few times but when it got near to no warranty left he sold it and got a new ebike.
now thats what he liked to do and in the 2 year warranty you will get the motor replaced no question if it is full of mud and did a few times but when it got near to no warranty left he sold it and got a new ebike.
I can only go by Fazua owners on Facebook and the general consensus is that fazua are great for support and I dont think they are any less reliable than Bosch. On the fazua bikes the entire drive pack is removable including the motor. Fazua can send out a new one or if it’s out of warranty you can get one on eBay. The bike can be used unassisted with no drive pack fitted too. The last plus for me is the PC software supplied reads fault diagnostics unlike Bosch which requires taking the bike to a dealer. My only regret from my old Bosch bike is that you can’t charge the battery on the bike, you need to unclip the drive pack to charge it.I've read a few forum posts about Fazua motors which have reliability concerns. A recent thread is this one where the owner is looking to get a more reliable motor system.
Reliability of e-bike systems
I have used a variety of ebikes over the years for my 12 miles each way daily cycle commute in all weathers. All have proved variably unreliable with connection faults, battery issues and failed components. I now have a Fazua-equipped Focus Paralane which is great when it works but pretty often...
However that said it sounds like he has gone through quite a few mid-drive motors so perhaps a particular powerful or heavy cyclist or maybe someone who does high number of miles.
A lot of it is about looking after the bike, l am on various forums and have read the "motor failure" threads
Often posted by owners who hammer their Ebikes off road, through water, in all weathers, covered in mud after every ride etc
l've got a Shimano E8000 motor and have had none of the motor issues reported on the forums, it's done 3,000 miles in the 12 months l've had it, a mixture on/off road and not ridden slowly.
However l don't ride it through rivers, and l don't use the maximum assistance level of 300% (l've got it set at 200% but l mostly use the "trail" mode which is 125% assistance)
l clean the bike and spray the electrical parts with GT-85 (or similar) to help protect it from moisture.
Often posted by owners who hammer their Ebikes off road, through water, in all weathers, covered in mud after every ride etc
l've got a Shimano E8000 motor and have had none of the motor issues reported on the forums, it's done 3,000 miles in the 12 months l've had it, a mixture on/off road and not ridden slowly.
However l don't ride it through rivers, and l don't use the maximum assistance level of 300% (l've got it set at 200% but l mostly use the "trail" mode which is 125% assistance)
l clean the bike and spray the electrical parts with GT-85 (or similar) to help protect it from moisture.
Fazua support is very good , if you are in warranty. But unfortunately bits have to go back to Germany. There are no spares for bottom bracket etc. Where as Bosch do a service kit for their motors.
Actual historical for a number of members in each case:
Giant Lafree Twist with Panasonic mid drive average consumption over time = 7.8 Wh per mile. Range typically 20 miles on its 156 Wh battery.
Ezee Torq or Quando with powerful hub motor average consumption over time = 24 Wh per mile. Range typically 15 miles from its 360 Wh battery.
I owned all three at the same time and concur with the other owners.
.
Presumably that Giant model is in eco mode to do that. Just looking at The Carrera Subway ebike at Halfords that does 40 miles in eco mode using the Suntour HESC system hub motor system with a torque sensor not cadence or at least not just cadence. That's a 318Wh battery so 7.6Wh per mile in eco mode or about 5Wh per kilometre. So like most mid-drive ebikes that particular ebike links rider effort to controller output. I guess the issue is how do the two bikes compare for actual assistance in eco mode though. How much extra torque are they providing in that mode. The issue is with a torque sensor it varies a lot. The Subway provides a peak torque of 60Nm.
While lots of mid-drive motors provide a throttle option and no pedal mode operation those are normally motors from Chinese brands, typically provided for kit builds. Most of the German mid-drive motors or motors focused on selling to Europe pre-built ebikes only allow a pedelec mode which means the only figure will look more efficient as it always includes the rider pedalling as well. The Subway is such a bike because its torque sensor based. If you compare a torque sensor based ebike vs cadence sensor based ebike both with hub motors the torque sensor based models normally have extended range because of the way the torque sensor operates.
Giant: Lafree Twist - ExtraEnergy.org
Light-weight pedelec with good bicycle qualities. Rating 2002: Good. Price: 1425.-
extraenergy.org
Carrera Subway E Mens Electric Hybrid Bike 2.0 - S, M, L Frames | Halfords UK
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www.halfords.com
For more range, if the controller allows it, slow down.
In the wake of Mike Burrows' sad passing, I rushed to my local online auction site and bought a copy of his excellent 'Bicycle Design' book. He points out that at normal riding speed, aerodynamic losses account for 90% or more of energy input for an upright riding stance. Aero losses are proportional to the square of speed, so range can be stretched a fair bit with a minor speed reduction.
24Wh per mile... ouch!
In the wake of Mike Burrows' sad passing, I rushed to my local online auction site and bought a copy of his excellent 'Bicycle Design' book. He points out that at normal riding speed, aerodynamic losses account for 90% or more of energy input for an upright riding stance. Aero losses are proportional to the square of speed, so range can be stretched a fair bit with a minor speed reduction.
24Wh per mile... ouch!
Such a brilliant man and very sad to hear. The worst cycling news I'd seen since the sad passing of Sheldon Brown. I don't have that book myself but I used to go into the Dorchester library when I had some time to spare and read a few bike books and I've never seen a tattier library book than Mike Burrow's Bicycle Design book. The pages were falling out and it must have been read by 100s of people. It was a reference book so couldn't be lent.
Still plan to pick up a Giant Halfway at some point. I do have a Giant road bike. It was the cheaper compact frame road bike the OCR for the masses where as was it the TCR I think he designed for professional racing with the same geometry. Mine is the very last model I think with a freewheel as the next version was freehub/cassette based.
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