Electric bike - see mode note post #298

ted1

1bryan wrote: »

Just curious as to whether people here have seen an increase in unregulated E-Bikes and electric scooters of late, or whether it's just me. Particularly in and close to town there seems to be people on electric scooters in the bike lanes. They don't seem capable of getting up much speed so they're a bit of a nuisance when you find one blocking you.

A bigger problem is the apparent increase in unregulated e-bikes. Almost daily I'm seeing people on bikes with actual motors attached (that make noise similar to a lawnmowers), and they're absolutely flying by at ridiculous speed.

It was easy enough to turn a blind eye to these when they were few and far between, but surely the time is coming that a clampdown is needed? Before someone gets seriously hurt.

What’s an unregulated ebike?

secman

ted1 wrote: »

What’s an unregulated ebike?

Think he's referring to MTB with petrol engine kit attached to them, have come across these not only in Dublin but in rural wexford, totally illegal.

ted1

secman wrote: »

Think he's referring to MTB with petrol engine kit attached to them, have come across these not only in Dublin but in rural wexford, totally illegal.

I was wondering as the e stands for electric!!
If it’s petrol it belongs in the motoring section!!

magicbastarder

If you said unregulated e-bike to me, I'd assume you were talking about a chipped one designed to provide power past 25km/h.

ED E

Yeah, its legally messy that as there are 750W units that have a road legal mode but its just a switch to change between illegal MPV and legal eBike.

Baron de Charlus

Baron de Charlus wrote: »

To put this into context, I'm in decent shape and got up the Wicklow Gap at a good lick the other week average 350w. I'm a big fella (90kg), so smaller riders would need less power than me to do it at the same speed.

Pretty much anyone with 250w assistance, no matter how out of shape they are, is going to get up the hills. I know this because I've seen it with my own two eyes.

Most people who are not daily cyclists and very fit will struggle to get up the Wicklow Gap even with a fully legally powered Bosch Bike.

There are also a lot of people heavier than 90 Kg and also people with Knee problems, My knees would struggle to get me up the wicklow Gap with a legal Bosch powered ebike and I'm not fit any more.

It's easy to say you could do it if you're fit in the first place.

The beauty of ebikes is it encourages people to get out and exercise and not fear hills or strong headwinds, exercise is exercise and I lost a tonne of weight in a illegal powered ebike some years ago when I first started building them.

Ebikes are also a lot heavier so need more power.

Again , it's not power that's the issue but acceleration and speed !

Bosch do now of course make ebikes with up to 75 nm of torque , mine has 50 nm.

Lumen

Deleted User wrote: »

Most people who are not daily cyclists and very fit will struggle to get up the Wicklow Gap even with a fully legally powered Bosch Bike.

There are also a lot of people heavier than 90 Kg and also people with Knee problems, My knees would struggle to get me up the wicklow Gap with a legal Bosch powered ebike and I'm not fit any more.

Why would you struggle? All you have to do is turn the pedals and let the 250W carry you up.

1bryan

magicbastarder wrote: »

If you said unregulated e-bike to me, I'd assume you were talking about a chipped one designed to provide power past 25km/h.

yeah, but it was a fair point. I meant both the e-bikes with the limiters removed, and regular bikes with motors attached. I should have been more specific.

magicbastarder

am seeing a lot more electric scooters around, have only seen one bike with a two stroke engine jerry rigged on in the last few months.

Lumen

Lumen wrote: »

Why would you struggle? All you have to do is turn the pedals and let the 250W carry you up.

No it does not work like this lol.

The likes of the Bosh ebikes do not allow you to just move the pedals, you have to put continuous substantial power in yourself, they use torque sensors some cheap bikes may use speed sensors with a lot less control over the motor and will feel rather jerky but the Bosch system is really smooth and responds to your input extremely well.

The bosch bikes also monitor cadence and torque so the more effort you put in the more assistance you get, the faster you pedal in low gear is were it gives you max power because the software thinks you would only be using max power on hills and would normally be in a lower gear peddling a lot faster so the bike senses this and applies max power and this is one reason where such low legal power limits are both meaningless and ridiculous because it's not power that's the danger it's speed and acceleration.

So like a normal bike, if you want more power for climbing very steep terrain you got to be in a low gear at a faster cadence and I know from experience when you get tired and your legs get tired most of the proper ebikes will not apply max assistance if you then slow down and run out of puff it will be rather difficult on steep hills.

yes indeed it's a huge help having the bikes but don't be fooled by thinking that because it's an ebike it's all easy peasy.

I quite like the Bosch system because it feels so much more natural but I really miss my throttle rear geared hub ebike which sometime I hope to reconstruct.

Lumen

OK, well something's wrong with the design if it can't get you up a gentle enough hill like the Wicklow Gap with 250W assistance.

Lumen

Lumen wrote: »

OK, well something's wrong with the design if it can't get you up a gentle enough hill like the Wicklow Gap with 250W assistance.

And your insane if you call the Wicklow gap a gentle hill, that's just ridiculous talk even getting up through Hollywood would be quite a struggle even for me now after so long off the bike. Hopefully I'll get back on it in the finer weather. I don't have much time these days unfortunately. Yes I could do it with the bike but as I said , if you get tired and your legs slow down power to the motor will be reduced, originally I liked the idea of making me work but I was a lot fitter then but better to have it than not. I did as I say get all the way to the RTE mast on it with considerable effort but the difference was being able to do it with the bike or not at all without it and I was a lot fitter then too.

I'd love one of the cargo bikes for carrying my 3 and 4.5 yr olds.

Something like this but the price....... 5,175 Euro's with the 75 Nm motor......

https://www.greenaer.ie/product/urban-arrow-cargo-bike/

A bike trailer is far too dangerous on the narrow country roads I travel. I would not feel comfortable at all with the boys in a low trailer at the rear not with the way people drive here.

This is where you need a lot more power too....250 Watts, ridiculous laws made up by E.U bureaucrats with no basic understanding of mechanics or electronics.

Lumen

Deleted User wrote: »

And your insane if you call the Wicklow gap a gentle hill, that's just ridiculous talk even getting up through Hollywood would be quite a struggle even for me now after so long off the bike.

It's only 5%. 300W (250W motor + 50W pedalling) will get an 85kg bike+rider combo up that at 20kph, which is fast.

Even if you're 120kg wth a 20kg bike, 300W will still get you up at 13.5kph, which is a fine speed for climbing.

I just can't make sense of the numbers you're quoting. 250W is loads.

Lumen

Lumen wrote: »

It's only 5%. 300W (250W motor + 50W pedalling) will get an 85kg bike+rider combo up that at 20kph, which is fast.

Even if you're 120kg wth a 20kg bike, 300W will still get you up at 13.5kph, which is a fine speed for climbing.

I just can't make sense of the numbers you're quoting. 250W is loads.

The bikes are more like 25 Kg, yeah probably 12-13 Km/h but the work by the rider is a lot on some of the steep stuff and depending on fitness and joints that can be very tough for sustained periods like climbing the Wicklow Gap or from Laragh to the Glenmalure Lodge and then head on for Aughavannagh that's some serious climbing.

The Bosch motors are great and while it is plenty to get up even slowly you will slow down as you get tired as your cadence slows so does motor output so it's not as easy as you think because the motor assistance drops if you or your legs get tired.

I'm pretty sure most of the other decent ebike systems would work like this.

Less Human input = less motor output, probably the simplest way I can explain it.

Power output is up to 75 Nm on some of the Bosch motors now up form the 45-50 of my Motor.

https://e-bikerumor.com/2018/07/22/eb18-haibike-unleashes-monstrous-120nm-tq-motors-prototype-emtbs/

A new motor with 120 Nm would be really sweet, that's a "LOT" more than my 45-50 Nm .

Lumen

Deleted User wrote: »

https://e-bikerumor.com/2018/07/22/eb18-haibike-unleashes-monstrous-120nm-tq-motors-prototype-emtbs/

A new motor with 120 Nm would be really sweet, that's a "LOT" more than my 45-50 Nm .

"Their latest upgrade is adoption of the all-new TQ 120S motor system, which packs a whopping 120Nm of torque into a nice round package. All that power is nothing without energy to make it turn..."

That's just wrong. Torque and power are not the same thing. Torque doesn't really matter, you can transform it with gearing.

I would have expected a website dedicated to e-bikes not to make such a basic error.

Lumen

Lumen wrote: »

"Their latest upgrade is adoption of the all-new TQ 120S motor system, which packs a whopping 120Nm of torque into a nice round package. All that power is nothing without energy to make it turn..."

That's just wrong. Torque and power are not the same thing. Torque doesn't really matter, you can transform it with gearing.

I would have expected a website dedicated to e-bikes not to make such a basic error.

What ? Please clarify.

Lumen

Deleted User wrote: »

What ? Please clarify.

Torque is a twisting force. It's meaningless in terms of motor output without knowing the speed at which it can be applied, but that would effectively just be stating the power.

Power is what counteracts gravity and drag. Power is rate of energy applied, or force applied at a speed, whatever suits.

If I have a fixed amount of power I can produce whatever torque I want through gearing/leverage.

Lumen

Lumen wrote: »

Torque is a twisting force. It's meaningless in terms of motor output without knowing the speed at which it can be applied, but that would effectively just be stating the power.

Power is what counteracts gravity and drag. Power is rate of energy applied, or force applied at a speed, whatever suits.

If I have a fixed amount of power I can produce whatever torque I want through gearing/leverage.

Yep get ye now,

You could also say that power in watts is what gives you the ability to move and torque is what makes you move.

But correct, with any given power you can create a target torque through gearing but also the motor Kva and torque applied.

In electric more current gives you more torque and more voltage gives you higher speed but you can manipulate both through gearing.

Chips Lovell

Deleted User wrote: »

Most people who are not daily cyclists and very fit will struggle to get up the Wicklow Gap even with a fully legally powered Bosch Bike.

There are also a lot of people heavier than 90 Kg and also people with Knee problems, My knees would struggle to get me up the wicklow Gap with a legal Bosch powered ebike and I'm not fit any more.

It's easy to say you could do it if you're fit in the first place.

I think you're misunderstanding me somewhat. What I'm saying is that to go up the Wicklow Gap fast, someone with an e-bike and equal weight would only have to put out a meagre 100w themselves.

Your average club cyclist would probably do that hill at something like 250w, meaning it'll take even less effort from the e-bike rider to do it at their speed.

Long story short, 250w is a substantial amount of assistance and will put most e-bike riders on a par with your average road rider. I know a seventy year old man, who's heavier than me, who can not only get up any hill on his legal e-bike, but is regularly passing lads on road bikes.

1,000w is crazy power. For a 100kg combined rider and bike weight, you'd be able to maintain a speed of 25kph up to a gradient of around 13%! That's something nobody, no matter how fit they are, can do on regularly bike.

well for starters the Bosch bikes and others are well above 250 watts but their average power is probably "officially" classed as 250.

Yeah 1 Kw is a lot of juice and a lot of fun on very slow steep trails.

Being fit and able to sustain the level of power V someone who is a lot heavier and not able to sustain the power are two completely different things.

I understand you perfectly well, you feel 250 watts / 500 or whatever is enough and for most part it is but there are times people don't want to put in so much effort on long sustained hills and more power is necessary the nanny state/E.U shouldn't be concerned power as I said because power is not the issue it/s speed and acceleration.

Also remember that some hub motor ebikes need a lot more power for the same torque on hills, so again, power is not the problem it's the lack of understanding of basic mechanics and electronics by people making up these ridiculous laws.

Think of an ebike as a exercise bike, you want to go out on a nice day and bring your child on the back and there are some hills, you don't want to kill yourself and you want to have fun and don't have all day to do it but you can still get plenty of exercise in the process should you wish.

Or you've been out longer than you intended and simply run out of puff etc, there are many situations more power is needed/wanted.

Lumen

The most obvious explanation for Mad_Lad's assertions that 250W is not enough, when every cyclist with a power meter knows different, is that the bikes Mad_Lad has ridden don't produce the output power (what the motoring people would call "power at the wheel(s)") that the wattage number suggests.

I dug a bit and found these:

https://www.ebikes.ca/learn/power-ratings.html (specifically the section "What about peak power rating?")

and relatedly

https://www.ebikes.ca/tools/simulator.html

Now I think these are only for hub motors, but it seems that there are considerable losses in the motor at high input currents, and peak power is only produced at high speed.

So it seems probable that some bikes, on slow steep hills, don't produce anything like the wattage that their marketing material suggests.

Yeah I was thinking about the simulator but as you pointed out it's only for Hub motors some which are much more efficient that others.

Some give much more torque at slower speeds than others who produce more at higher speeds.

Some hub motors have internal gearing for more torque and better efficiency,

On hills especially slow steep trails mid mount or chain drive motors are better, more torque for the same power ( usually ) and run much more efficient because the motor can spin in it's efficient zone and if it bogs down just select a lower gear.

Usually all you need to do to get a higher top speed is to apply more voltage and more torque you just apply more current.

Remember I said the Bosch motor took me up mount leinster from the bottom at the access gate to the RTE mast , that's one hell of a climb that I would not have been able to do without the motor, I burned hubs at 3 Kw but the Bosch didn't trip due to thermal issues what so ever, I did it with much less power, the Hub was converting most of the energy to heat as it becomes very inefficient at those speeds and the Bosch did it with 500 watts max.

Some of the Bosch bikes have a rear gear hub , Sram dual drive 3 is the one on my bike and this allowed me the gearing I needed to climb but very slowly. Other ebikes might not have the gearing for the really strep stuff.

So 100 watts will get you up walls with the right gearing but not at a speed anyone would like hence the need/desire for more power.

But I know where ye lads are coming from, ye feel 250 watts is enough so that's absolutely the maximum ye feel anyone should ever have but what ye feel is good enough is not what I or many others would feel good enough.

My Bosch with 45 Nm of torque is good enough most of the time but but sometimes I want a bit of exercise and to get out in the fresh air without busting my balls.

Play with the simulator,

Use the MAC 12T motor which is a high torque, internally geared motor, I had the 8T. ( at the bottom of the drop down box select all motors )

Feed it 52 volts, 35a controller and 15% grade

You see 1200 watts consumed and top speed of 25.5 Km/h on 15% grade, that's nice. At this speed it's producing 60 Nm of torque V 115 Nm at up to 5 Kmh.

Efficiency is 77.8%

Now select clyte 3540 which is a direct drive motor, no internal gearing.

Now about 50 Nm of torque but at 23 Kmh

Efficiency is 63%

However, the other thing about direct drive hubs is that they are a devil to pedal without power due to the drag of the motor, the geared hub disconnects the drive to the motor via clutch so it freewheels much much better.

The bafang diy kits , chain drive claim about 115 Nm torque and it's larger brother the BBSHD 160 Nm.

Bosch now claim up to 75 Nm form some versions of their motors.

Here's pics of my old Ebike, I could easily get up to 40 Mph on this, notice the size compared to the brake disk. These were standard brake disks that came with the bike but had not got nearly enough braking power at this speed so I upgraded them to 8 inch disks, I can't find that pic bit the difference in stopping power was massive.

This was the 8T version of the MAC Motor which you can find in the ebikes.ca simulator liked to in a previous post. It's internally geared and vastly superior to direct drive motors.

I was feeding it with about 60 volts powered by a LiPo battery , as I like to cycle the battery had to be small and to give me the power needed for 40 Mph I had to use LiPo batteries which have massive power density and minimal voltage sag under load.

Here's the bike, notice Carlow Town in the background and the remains of the old sugar factory to the left of the ESB pole. I really do miss that bike !



Notice the steel dropout reinforcement , you simply can not have any decent power going to the rear axel without proper reinforcement.

1bryan

Fair play Mad_Lad, you certainly know your stuff.

1bryan

1bryan wrote: »

Fair play Mad_Lad, you certainly know your stuff.

Cheers, It was more for experimentation, a hobby than anything else.

I decommissioned it sadly, nearly 6 years ago when I got the Haibike EQ trekking in about July 2013. Wow, when I think about it where the hell does the time go ? seems like yesterday I built the bike with the MAC motor and that was 8 years ago, Jesus it's insane.

I hope to make a good attempt to get back on the bike this year, I don't have a lot of time having 2 small Children and working shift, I get lots of time off but busy in between and knackered most of it. Sooner I get off shift the better.

I would love to try building another ebike, using the Bafang BBS02 or BBSHD motor, the BBS02 would probably be plenty powerful for me, this time I'm not looking for mad speed and acceleration.

120 Nm torque and 160 Nm torque for the BBSHD available in all gears unlike hub motors which can struggle on steep hills, unless you feed them lots of power.

I got up Mount Leinster all the way to the RTE Mast with the Bosch motor using about 500 watts max and burned a big hub motor at 3 Kw. So chain drive motors are definitely king for very slow and very steep trails, anyone who knows Mount Leinster knows how steep it is, it's over 20% in places and coming back down is more dangerous than going up it will smoke your brakes lol. Some efficiency difference too between the hub and chain drive.

I did it on the Bosch but was very, very tough with 50 Nm torque so 120 would make a big difference. Only for the Sram Dual Drive 3, 3 speed hub on the rear I probably would not have made it it gave me the gearing needed for such a climb.

So yeah the Bosch motors will climb pretty much anything particularly the newer 75 Nm torque versions which I would like to try out but I got the ebike building bug back lol a Man need hobbies to keep the mind healthy , and more torque makes it more fun lol.

Even though the BBS02 and BBSHD exceed legal limits they come with 25 Km/h limits applied and if not you can set these limits, remember that watts are not dangerous only speed and acceleration.

Thargor

The minute the ranges improve to 80-100 km Ill be building one, 30-50km is no good to me. I love cycling and its how I commute and my main source of fitness but I absolutely hate hills, as in hate, hate, hate them, Im allergic to climbing. I live in Bray so any direction you travel really means loads of hill climbing and it often puts me off going out for a ride in the Sally/Wicklow gaps when the weather isnt perfect. I can basically pedal forever on the flat, done 100 km+ on the canals a load of times even though the rough ground and my crappy old Raleigh MTB probably takes twice as much energy as a few hills on my roadbike.

My ideal build would be basically a hybrid/trekking bike thats basically an electric motorbike, I dont care about the laws, 100-150km range, seamless transition between motorbike mode/pedal bike. Its just a case of waiting for the battery tech to improve, which it is at a rapid rate these days.

beauf

You can cycle as far as you want and only turn it on for the hills.

Thargor

Thargor wrote: »

The minute the ranges improve to 80-100 km Ill be building one, 30-50km is no good to me. I love cycling and its how I commute and my main source of fitness but I absolutely hate hills, as in hate, hate, hate them, Im allergic to climbing. I live in Bray so any direction you travel really means loads of hill climbing and it often puts me off going out for a ride in the Sally/Wicklow gaps when the weather isnt perfect. I can basically pedal forever on the flat, done 100 km+ on the canals a load of times even though the rough ground and my crappy old Raleigh MTB probably takes twice as much energy as a few hills on my roadbike.

My ideal build would be basically a hybrid/trekking bike thats basically an electric motorbike, I dont care about the laws, 100-150km range, seamless transition between motorbike mode/pedal bike. Its just a case of waiting for the battery tech to improve, which it is at a rapid rate these days.

What are you looking for ? Speed or just hill climbing ability ?

You can always add a 2nd battery or carry a spare which would give you a lot of range if you put the effort it and as said above use it only for the hills, it will be heavier though.

The chain drives are the way to go for efficiency on the hills.

At bike speeds you can easily do 100 Km with the current gen Ebikes with 500 Watt hr batteries with a lot of peddling on hills.

But if you're after speed and throttle only for 100-150 Kms then you will be waiting years I'm afraid before battery tech gets that good in the size suitable for a bicycle.