Who needs more than 250W?

Electrically assisted bikes, trikes, etc. that are legal in the UK
Oldjohnw
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Re: Who needs more than 250W?

Post by Oldjohnw »

peterb wrote: 18 Jul 2021, 6:51pm
Oldjohnw wrote: 18 Jul 2021, 6:12pm Here are lots of things I can’t do that I could a few years ago. I am daily thankful that I can do what I do. Being grateful for what I have seems a reasonable feeling. An ebike has enabled me to keep going beyond what would have otherwise been possible. I can’t climb mountains which is disappointing and there is not an electronic gadget available to help. But I look for different things now and they are no less rewarding.

The general name for this condition is ‘getting older’. If you are lucky, it happens to you.
I agree. I can't climb mountains any more, I can't even walk far without great pain. There are many with my problem who can't walk as far as me, there are many who have had to have limbs amputated. I'm very lucky. I can't ride the bikes listed below more than a very few miles. But there is an electronic gadget that allows me to continue enjoying cycling. Just 3mph added to the assistance level, available to me if required - what's the problem?
I did not mean to come act unsympathetic and if I did, my apologies.

There is no problem with wanting another 3mph. It just isn’t available. The difference it would make to a longer trip would be pretty minimal: 10 minutes less for a 15 mile journey.
John
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mjr
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Re: Who needs more than 250W?

Post by mjr »

peterb wrote: 18 Jul 2021, 6:39pm
mjr wrote: 18 Jul 2021, 5:27pm
You can have feelings of regret for it, but why does that mean the legal limits should be raised? Would the improved mental health of people in your situation outweigh the increased potential damage to riders and anyone hit?
Evidence? The legal assisted limit for my bike (exactly the same 250w model) in USA and Canada is 20mph, has this caused damage and death? 15.5mph is a purely arbitrary figure.
I don't know. You're arguing for a change: show us the numbers.
MJR, mostly pedalling 3-speed roadsters. KL+West Norfolk BUG incl social easy rides http://www.klwnbug.co.uk
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peterb
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Re: Who needs more than 250W?

Post by peterb »

mjr wrote: 18 Jul 2021, 8:02pm
peterb wrote: 18 Jul 2021, 6:39pm
mjr wrote: 18 Jul 2021, 5:27pm
You can have feelings of regret for it, but why does that mean the legal limits should be raised? Would the improved mental health of people in your situation outweigh the increased potential damage to riders and anyone hit?
Evidence? The legal assisted limit for my bike (exactly the same 250w model) in USA and Canada is 20mph, has this caused damage and death? 15.5mph is a purely arbitrary figure.
I don't know. You're arguing for a change: show us the numbers.
I can't be bothered - you suggested the dire consequences - on what basis. Maybe the current cut off should be reduced to 10mph. This would presumably save a lot of death and destruction. Perhaps all bicycles should be restricted to 10mph.
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[XAP]Bob
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Re: Who needs more than 250W?

Post by [XAP]Bob »

The 20mph is no less arbitrary than the 25kph limit over here.

You are free to get an electric moped/scooter license and up the power appropriately.

After all "what does an extra few miles an hour matter" says every motorist as they speed through town.
That's what the limit is, and it's sensibly harmonised across a large number of countries, meaning that manufacturers don't need to produce Britain specific models with all the extra cost that would entail. It means we can take our vehicles overseas with relative ease.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
There are two kinds of people in this world: those can extrapolate from incomplete data.
peterb
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Re: Who needs more than 250W?

Post by peterb »

Britain specific? The only difference between the USA Orbea Gain and the European one is the software.
Anyway, I know the assisted speed cut-off of 25kph is not going to change any time soon and there is no way I'll be caught dead riding an ugly lump of an electric moped, or defacing an (e)road bike with number-plates whilst wearing a motorcycle style helmet, so I'll have to put up with it. By the way to return to the original topic - no, I don't need more than 250W.
That's all from me for now... thanks for a sympathetic hearing.
hemo
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Re: Who needs more than 250W?

Post by hemo »

The so called arbitrary limit of 15.5mph was decided on for European bikes having taken the limit used by the Japanese, Panasonic, Yamaha & Satura likely some of the first ebikes made and this is the figure they felt was a safe limit for an average non sports rider. If one looks back to the UK limit it was even less at 12mph before harmonising legally with Europe also along with the wattage rating of 250w. It wasn't until 2015 I believe that most UK ebikes were in fact illegal as the UK rating was only 200w, hence why a lot of the older brands like powerbyke were 200w only.
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mjr
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Re: Who needs more than 250W?

Post by mjr »

peterb wrote: 19 Jul 2021, 7:43am
mjr wrote: 18 Jul 2021, 8:02pm
peterb wrote: 18 Jul 2021, 6:39pm

Evidence? The legal assisted limit for my bike (exactly the same 250w model) in USA and Canada is 20mph, has this caused damage and death? 15.5mph is a purely arbitrary figure.
I don't know. You're arguing for a change: show us the numbers.
I can't be [rude word removed] - you suggested the dire consequences - on what basis.
I suggested a small increase in damage, based on physics, not dire consequences. Misrepresenting the argument against a proposal is often a sign that the proposal is weak.
Maybe the current cut off should be reduced to 10mph. This would presumably save a lot of death and destruction. Perhaps all bicycles should be restricted to 10mph.
Reducing the current cut off would make even less sense than raising it. Restricting all bicycles would do massive harm to people's health and the environment as almost everyone wanting to travel faster switched to motorised transport. These are fairly simple arguments against those ideas which don't support the idea of further raising of the speed and power limits.
MJR, mostly pedalling 3-speed roadsters. KL+West Norfolk BUG incl social easy rides http://www.klwnbug.co.uk
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jb
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Re: Who needs more than 250W?

Post by jb »

"Ello ello ello what's all this ere then? It appears to me that sir was proceeding along at seventeen mph AND being given helectrical assistance. I will hav no halternative than to set you before the beak who will send sir to the colonies to do some ard labour that will make that stolen '2mph' a highly regretable decision so it will"

I think not - tweak the soft ware like wot all the kids do.
Cheers
J Bro
francovendee
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Re: Who needs more than 250W?

Post by francovendee »

I don't want to get into a debate about speeds etc of an ebike. There's already plenty of opinions on this matter in this this thread.
My question is about the merits of a 36 volt or a 48 volt mid drive motor. Is there a lot of difference? I'm looking for a bit of help on steep hills but intend to not use the motor most of the time.
stodd
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Re: Who needs more than 250W?

Post by stodd »

All else being equal (eg controller rating, batter current delivery, etc) a 48v system should give 33% extra torque at low speeds, which will be especially useful for hills.
fivebikes
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Re: Who needs more than 250W?

Post by fivebikes »

Avoided this one up until now because, as an ebike user, Swytch Brompton and ARCC Moulton, I’m happy with the wattage and limit. I know I can change the cut off on the Swytch very easily… a couple of button presses on the very basic control panel but I won’t. In fact, away from hilly Yorkshire don’t really need it! A weekend on the Redways in Milton Keynes was power off! Otherwise I’d have kept having to stop for non assisted friends on our leisurely potter (15 kph max) around the outlying villages and more urban bits. Had to be mindful of walkers, buggy pushers, other steady cyclists and the food delivery robots!! that share the redways.
Out on the open road I seldom see cyclists keeping up with the traffic except (occasionally) in 20mph zones and crawling through hold ups (often no more than walking pace!).
E moped riders are another matter… generally no plates, helmet, blah blah… even the ones used by local food delivery places! Saw one guy yesterday tailgating a car a car doing 30 ish up a steep hill near me. Feet on pedals but not pedalling! How many watts was he on? I guess big watts are important for this and pulling serious wheelies which I see a lot of too. Through traffic too ‘cos what’s the point unless people can see and admire/get angry? He did have his hood up and was showing a tiny red led tail light so all was well.
The Police are too busy to stop and check even people like this so tweaked or speed ebikes will not arouse suspicion.
For those old enough to remember… “Let’s be careful out there”
offroader
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Re: Who needs more than 250W?

Post by offroader »

francovendee wrote:I don't want to get into a debate about speeds etc of an ebike. There's already plenty of opinions on this matter in this this thread.
My question is about the merits of a 36 volt or a 48 volt mid drive motor. Is there a lot of difference? I'm looking for a bit of help on steep hills but intend to not use the motor most of the time.
If you're talking native 36V systems vs native 48V systems then there shouldn't be any performance difference as the motor and battery should be designed to work together to meet the design requirements
However it's worth noting that these days 36V is often fitted to lower spec bikes so if you're comparing a 36V Happy Shopper setup to a 48V Bosch system there is likely to be a performance difference

In general while there shouldn't be a performance difference there are/should be efficiency benefits and packaging gains to higher voltage systems. That's why cars, F1 hybrids etc use dangerously high voltage


If you're talking about ramming 48V up a 36V systems chuff then you'll see a ~70% increase in power. Or a cloud of smoke
PH
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Re: Who needs more than 250W?

Post by PH »

offroader wrote: 7 Sep 2021, 9:12pm However it's worth noting that these days 36V is often fitted to lower spec bikes so if you're comparing a 36V Happy Shopper setup to a 48V Bosch system there is likely to be a performance difference
I thought the systems of all the major players, Bosch, Shimano, Yamaha, were 36V?
francovendee
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Re: Who needs more than 250W?

Post by francovendee »

offroader wrote: 7 Sep 2021, 9:12pm
francovendee wrote:I don't want to get into a debate about speeds etc of an ebike. There's already plenty of opinions on this matter in this this thread.
My question is about the merits of a 36 volt or a 48 volt mid drive motor. Is there a lot of difference? I'm looking for a bit of help on steep hills but intend to not use the motor most of the time.
If you're talking native 36V systems vs native 48V systems then there shouldn't be any performance difference as the motor and battery should be designed to work together to meet the design requirements
However it's worth noting that these days 36V is often fitted to lower spec bikes so if you're comparing a 36V Happy Shopper setup to a 48V Bosch system there is likely to be a performance difference

In general while there shouldn't be a performance difference there are/should be efficiency benefits and packaging gains to higher voltage systems. That's why cars, F1 hybrids etc use dangerously high voltage


If you're talking about ramming 48V up a 36V systems chuff then you'll see a ~70% increase in power. Or a cloud of smoke
I'm going to fit a Bafang motor and I see they come in various voltages. Apart from the need for speed I wondered if the higher the voltage the longer the range. I suspect it's not, and more a function of the battery size?
stodd
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Re: Who needs more than 250W?

Post by stodd »

francovendee wrote: 8 Sep 2021, 8:39am I wondered if the higher the voltage the longer the range. I suspect it's not, and more a function of the battery size?
Range is almost completely a linear function of battery capacity, as measured in Wh (watt hours), and of course riding style/conditions. Some people quote Ah (amp hours), which needs to be multiplied up by voltage to get true Wh capacity.

You probably get marginally less range (per Wh) from a 48v system as you are likely to use slightly more assistance. If you cycle carefully at a low setting the range difference will be very small.

You can get an idea from https://www.bosch-ebike.com/en/service/range-assistant/
Even though I think all their motors are 36v (?), the differences between 36v and 48v on a given motor, and the different 36v motors they show will be similar. As you will see, cycling style and conditions make huge differences to range, different motors make relatively little difference.
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