Need help choosing between these bikes

[TheBag]

I've finally narrowed down my choice of ebikes based on lots of reading and plenty of help from the pedelecs community.

I've significantly raised my budget from under 1000 to around 1500 in order to get a decent bike so if there's any obvious bikes I've missed in this price range, let me know.

The choices are:
Cube Acid Hybrid One 400 29er 2019 - Electric Mountain Bike
Haibike SDURO Cross 1.0 700c 2019 - Electric Hybrid Bike
Oxygen S-CROSS MTB Electric Mountain Bike
905 SE Crossbar
905 Torque Crossbar
Woosh Rio MTB

There are a few various deals on some of these so price differences might not be as big as they look.

To clarify once more, I won't be doing many miles each day, probably close to 3 miles per day now that I think of it, but some steep hills on the journey which I don't want to be sweating buckets when I reach the top.

Who knows, I might actually enjoy cycling and decide to do more than just commute to the train station.

Thanks for any advice you can give.

 

[Woosh]

the Woosh Rio MTB with 17AH (£1,269) will be back in stock on May 25th.

I like the Cube though.

 

[Amoto65]

Hi, That is a great selection to choose from, possibly one bike you are missing is the Carrera Crossfuse at Halfords if it comes down in price again. I have got a Crossfuse and a Wisper 905se and they are both excellent in there own way, the Crossfuse has the same motor as the Cube and the Haibike and was available for about £1200 earlier in the year. A lot of it depends on your level of fitness, another thing to consider is are the bikes available locally in the event of any problems. Cheers Steve W....

 

[TheBag]

Very good to know and something useful to consider. I'm not crazily fit although I'm definitely not overweight at all. 5"11' and 12.5 stone.

I live in North West London (just inside the M25 but technically in Hertfordshire). No idea if that's good for local dealers or not but there are a few Halfords around as you'd expect.

Thanks for the recommendations so far!

 

[TheBag]

Crossfuse has the same motor as the Cube and the Haibike and was available for about £1200 earlier in the year

The crossfuse looks to be 1800 at the moment so I don't think it's worthwhile at that price

 

[Amoto65]

I would agree at that price but Halfords very often discount bikes so maybe worth keeping an eye on it while you are looking.

 

[barbel]

crosspath 18"£1400
crosspath 20"£1280
pendleton black £850
pendleton white £750
halfords why?

 

[TheBag]

crosspath 18"£1400
crosspath 20"£1280
pendleton black £850
pendleton white £750
halfords why?

Firstly I'd say that the Pendletons aren't in the same sort of range as the rest and secondly I don't want a step-through bike.

I'd also prefer the option of at least going through a bit of rougher terrain.

If I'm being ignorant, please feel free to point it out as I don't know much in this space.

 

[MarcusT]

For me; a mid mount motor is the way to go.

 

[TheBag]

For me; a mid mount motor is the way to go.

I think the only ones from my list which are not hub motors are the haibike and the cube. Do you have any other bikes i should consider?

 

[Woosh]

I think the only ones from my list which are not hub motors are the haibike and the cube. Do you have any other bikes i should consider?

the Woosh Krieger has a crank drive motor, gear shift sensor and a throttle. Hydraulic brakes, SR NEX suspension fork.
15AH (£1,179) or 17AH (£1,229) battery.

The Woosh Krieger CD | Chain Drive Electric Bikes from Woosh

The Krieger: electric mountain bikes from Woosh with crank drive motor, automatic gearshift sensing and 15AH/17AH battery.

wooshbikes.co.uk

 

[TheBag]

the Woosh Krieger has a crank drive motor, gear shift sensor and a throttle. Hydraulic brakes, SR NEX suspension fork.
15AH (£1,179) or 17AH (£1,229) battery.

The Woosh Krieger CD | Chain Drive Electric Bikes from Woosh

The Krieger: electric mountain bikes from Woosh with crank drive motor, automatic gearshift sensing and 15AH/17AH battery.

wooshbikes.co.uk

I don't know enough about the difference between a hub vs crank motor in terms of what they do to the ride. I just want something that will last me and will not need an immediate upgrade if i decide I enjoy cycling and want to do more than just my commute each day.

How does the Krieger compare against the Rio? They both look like the fill a similar role?

 

[TheBag]

I also just noticed this warning on the woosh krieger web page:

Crank drive is not recommended if:
- You can't pedal fast.
The strain and stress on the motor is inversely proportional to your cadence. If you pedal slowly, under 30 RPM, most of your battery power will be converted to heat, not good for the motor.

What does that mean in real terms? I am not planning to pedal ridiculously hard uphill which is where I will need the motor the most. Is it a case of sticking it in first gear and just moving the pedals around or do I actually need to be putting in effort? I also thought many people use an open full throttle up hills - surely this would destroy motors.

The other things I've just been reading is about gear changes on crank motors. Is it true that if you don't remember to switch down gear before you come to a stop, you can't change gear until you start moving? Is it also true that changing gears while using the throttle is really bad and that you need to be careful or have some kind of controller installed to cut power when changing etc?

 

[Woosh]

I also just noticed this warning on the woosh krieger web page:
What does that mean in real terms? I am not planning to pedal ridiculously hard uphill which is where I will need the motor the most. Is it a case of sticking it in first gear and just moving the pedals around or do I actually need to be putting in effort? I also thought many people use an open full throttle up hills - surely this would destroy motors.

let's compare the two tactics when riding up a 10% hill: speed 10mph, 144 RPM at the wheels, power required: 500W
first tactic, go up a 10% hill in 7th gear (13T), pedal hard help the bike, you would pedal at 42RPM
second tactic: leave the bike in 1st gear (28T) and ride on throttle, the chainring would turn at 91RPM.
For the same output power, if 100% is the amount of heat produced when the motor spins at 42 RPM, it will produce about 60% of the heat at 91RPM.
The best compromise is when the motor spins at between 70RPM and 80 RPM.
You go up that hill in the 5th gear (21T) and pedal at 68RPM where the motor is at its most efficient and produces least heat for the same hill at the same speed.

The other things I've just been reading is about gear changes on crank motors. Is it true that if you don't remember to switch down gear before you come to a stop, you can't change gear until you start moving? Is it also true that changing gears while using the throttle is really bad and that you need to be careful or have some kind of controller installed to cut power when changing etc?

The Krieger has a gear shift sensor, it cuts the power when it senses the gear cable move. Change gear like on a normal bike.

 

[TheBag]

let's compare the two tactics when riding up a 10% hill: speed 10mph, 144 RPM at the wheels, power required: 500W
first tactic, go up a 10% hill in 7th gear (13T), pedal hard help the bike, you would pedal at 42RPM
second tactic: leave the bike in 1st gear (28T) and ride on throttle, the chainring would turn at 91RPM.
For the same output power, if 100% is the amount of heat produced when the motor spins at 42 RPM, it will produce about 60% of the heat at 91RPM.
The best compromise is when the motor spins at between 70RPM and 80 RPM.
You go up that hill in the 5th gear (21T) and pedal at 68RPM where the motor is at its most efficient and produces least heat for the same hill at the same speed.

Thank you very much for the detailed response - some really useful information there. I just have a couple of questions which I apologise in advance for if they are stupid.

1. What is 13T, 28T etc. I'm assuming the T stands for torque or something along those lines?
2. Is the heat generated based purely on RPM rather that what I'd expect to be power output? I.e. if the motor is going full power in 1st gear up a steep hill vs 10th gear on the same hill, it would surely do more RPM in 1st gear and so would get hotter?

I expect to be pedalling, but I want to feel comfortable that as my journey home is predominantly uphill, I'm not having to struggle and if I'm not struggling, that I'm also not damaging the bike.

I don't think you answered the other question I asked either

The other things I've just been reading is about gear changes on crank motors. Is it true that if you don't remember to switch down gear before you come to a stop, you can't change gear until you start moving?

 

[Artstu]

The T is for teeth on the rear sprocket.

 

[TheBag]

The T is for teeth on the rear sprocket.

ahh - that makes sense, thanks!

 

[Woosh]

Is the heat generated based purely on RPM rather that what I'd expect to be power output? I.e. if the motor is going full power in 1st gear up a steep hill vs 10th gear on the same hill, it would surely do more RPM in 1st gear and so would get hotter?

the amount of heat generated by the motor is the difference between the energy supplied by the battery (input) and the mechanical energy that the motor sends to the chain (output). We call the ratio output/input the motor yield.
It's zero when the motor stalls, 100% of the input energy will turn into heat. At its best, the motor yield is 83% @ 75-80 RPM. Some 17% of the input is still turned into heat. At 30-40 RPM, 40% of the input is turned into heat.
In the example I gave before, climbing 10% hill at 10mph can shed as much as 150W-200W in heat when you select the wrong gear (7th, 13T). That will damage the motor in the long run.
You can of course climb steeper gradients but you have to climb more slowly and in first gear (28T).

 

[Woosh]

I don't think you answered the other question I asked either.

The other things I've just been reading is about gear changes on crank motors. Is it true that if you don't remember to switch down gear before you come to a stop, you can't change gear until you start moving?

you can't change gear until you start moving?
that is not quite true. Certainly not for derailleur gears. Hub gears tend stick under load, so forcing it to shift is very unkind to the bike. For derailleur gear, if your chain is under tension, it will make a bit of noise when engaging a larger cog but certainly not sticky as such. The gear shift sensor practically eliminates the chain banging or mashing noise when shifting on hill.

 

[TheBag]

the amount of heat generated by the motor is the difference between the energy supplied by the battery (input) and the mechanical energy that the motor sends to the chain (output). We call the ratio output/input the motor yield.
It's zero when the motor stalls, 100% of the input energy will turn into heat. At its best, the motor yield is 83% @ 75-80 RPM. Some 17% of the input is still turned into heat. At 30-40 RPM, 40% of the input is turned into heat.
In the example I gave before, climbing 10% hill at 10mph can shed as much as 150W-200W in heat when you select the wrong gear (7th, 13T). That will damage the motor in the long run.
You can of course climb steeper gradients but you have to climb more slowly and in first gear (28T).

I very much appreciate the detailed explanations you're giving me. If it doesn't seem so, I want to be sure to make sure I state it specifically as although I am not an engineer or physicist, I very much like to understand things properly as it helps me learn and retain the information as well as use it effectively.

So, if 75-80 RPM is ideal for motor yield efficiency then we can assume that the aim should be to keep the motor at this speed by selecting the correct gear. If the example you gave earlier (10% incline, first gear, riding solely on throttle) results in 91 RPM, if you switched up to 2nd or 3rd let's say, could this bring the rpm down to the most efficient range and you could then ride entirely on throttle up the hill while keeping the heat loss at ~17%?

Again I apologise if it's a stupid question and you really don't have to entertain my questions give me a physics lesson on here if you don't want to - I'm very happy with the information you've provided so far!

What I'm ultimately trying to determine is if a crank motor will mean that I have to pedal too hard up the hills near me. The predictor on your website shows my journey as the following: