I'm 15 stone I wish to buy an legal 250w.

[quackstar84]

That is the most important thing. That your ride makes you wanna ride more and more.
I am 16 stone sharp and 500W DD fed with 1kw on a velomobile is definitely not overpowered on hills. I have to pedal hard if the hill is steep to get on the top.
i just lost one stone by just cutting out the added sugar. Added sugar is everywhere, it takes some investigation to find it. I still eat Whoppers occasionally. It"s not bad if you take it w/o cheese and without anything else, just the burger. Pretty good meal. Burgers are not bad, it all them other things that people usually take with them that are bad.
Beer is very bad. Estrogen-carbohydrate liquid.

An velomobile would be ideal for me and my pots. Recumbent exercise bikes do not trigger pots so that position would be great. Yeah I avoid sugar now, I only drink diet pepsi about once every two weeks as a treat. When you see what 50 odd grams of sugar looks like and how they manage to fit it in to cans of pop, it is a wake up call.

Yeah I don't drink alcohol either. Cheers.

 

[quackstar84]

My 500 W Q128c won't get my 12 stone up my hills without significant pedalling effort, but I guess what works for you depends on topography and the amount of effort you are willing to put in. I would opt for the 1000 W system. If your controller or cycle analyst can limit the amps, it becomes a lower power motor anyway. A 500-1000 W geared hub like a Mac would have excellent hill climbing abilities and doesn't drag with resistance when pedalling unpowered unlike dd hubs.

Yeah my controller is basic and I do not believe an cycle analyst would be compatible. I'd like to have an on board computer as well as I do like data.

Agreed, in most places, the cops will overlook you if you aren't hooliganing it around town, but you know best... In worst case scenario, I'd limit the amps on a Mac to be as near to legal as you can get away with, then install a hidden turbo button for the hills If you're not speeding, the only way the cops can prove your bike is too powerful is to put it on a dyno. You might also argue the max power laws discriminate against the heavier rider by making a normal ebike commute impossible and that you limited the power as much as reasonable for it to still be usable; max speed would be fairer.

I'm pretty smart and sensible so I wouldn't be daft around my local town, in fact I'd just stay away from crowed areas. What happens if I have an accident and harm someone thought? I mean it's common for normal cyclists to not have insurance here but to be riding an illegal as well =/

I few years back on this site a member made me aware that I could cut one of the shunts off to remove amps, is that correct? Would that just reduce the torque thought? I'd still be able to reach 30mph?

There are lots of resources and people here to help with repairing batteries, and they're not that complicated. You might have to replace the power leads, a few cells or perhaps the BMS. Consider a replacement as well; you can always use it for that second build - or while you work out the problems with your first battery... Never hurts to have a spare ebike, especially if it keeps you active while you deal with something that breaks.

Yeah i'll have to get some photos of it soon. And see what people make of it. Cheers.

 

[quackstar84]

Cheers for your time everyone. Sorry for making many posts but I like to reply to people who have taken their time to reply to me.

 

[ddk]

of course it will work... kinda.
Case in point this trike, with me on it weighs 36 stone.
Notice the front wheel...View attachment 1
Put a little motor in a little wheel and voila... (also known as: gearing down)
So consider using a small folder as your bike so its' tiny wheels don't look out of place...

 

[molybdenum]

Yeah my controller is basic and I do not believe an cycle analyst would be compatible. I'd like to have an on board computer as well as I do like data.

Some members have retrofitted their controllers with CA inputs - it's not for the faint of heart however. There are inexpensive controller/LCD combos available with programmable features - BMS battery comes to mind.

I'm pretty smart and sensible so I wouldn't be daft around my local town, in fact I'd just stay away from crowed areas. What happens if I have an accident and harm someone thought? I mean it's common for normal cyclists to not have insurance here but to be riding an illegal as well =/

I'm not that concerned about being pulled over by the police - it's more about liability and coverage: I was hit by a car in a freak accident while riding last October and I went by ambulance to the hospital while my bike went to the police station. Had I been riding something illegal, I doubt the driver's insurance would have covered my losses, medical expenses etc. In your case, a legal ebike may be impracticable and will certainly never do 30 mph.

I few years back on this site a member made me aware that I could cut one of the shunts off to remove amps, is that correct? Would that just reduce the torque thought? I'd still be able to reach 30mph?

It is voltage that determines speed and amps determines torque. Of course, you need a certain amount of torque to overcome wind resistance and frictional losses to achieve your top speed - and you could limit amps to the point where 48V would be insufficient to attain 30 mph. I'm guessing you'd need at least 700-800W to maintain these speeds on flat ground (maybe more), so at least 15-20 amps? - not exactly legal. Strong pedalling will add 150-250W to the motor, and is good for the heart and soul. Cutting the shunt will reduce amps and can be reversed with a bit of solder, but it involves opening up the controller each time. Far more convenient to regulate the max amps through a programmable controller etc.

Yeah i'll have to get some photos of it soon. And see what people make of it. Cheers.

We look forward to the pics...

 

[d8veh]

250w rating doesn't mean anything. There's some very powerful "250w" motors. The only relevant legal requirements are that the motor has to be marked or catalogued at 250w and limited to 25 km/h. There's no limit on how much power you push through it.

Isn't there a limit to how many watts it could handle before burning out thought?

Thank you for your information. I'll be sticking to my front 48v 1000watt and either repairing the battery or buying a new one.

You're not getting it. A guy is selling 250w BBS01s in Norway. They're marked 250w 36v 25 amps. Heinzmann were selling 250w geared hub motors with 36v 28 amp controllers. Ezee sell a 500w motor in USA. They sell a 250w one in the UK. Do you know the difference, or shall I tell you? None of those motors burn out.

Some people want an electric moped, others want an electric bicycle. Only OP knows what he wants. I'm nearly 18st and live in a very hilly part of the country with hills as steep as 32% on my regular rides. I'm happy with my "250w" electric bicycle, that hasn't burnt out in nearly 5000 miles.

 

[quackstar84]

of course it will work... kinda.
Case in point this trike, with me on it weighs 36 stone.
Notice the front wheel...View attachment 1
Put a little motor in a little wheel and voila... (also known as: gearing down)
So consider using a small folder as your bike so its' tiny wheels don't look out of place...

Goodness that doesn't come across as aerodynamic... although it will keep you dry.

What battery are you using?

So it must acceleration slowly?

 

[quackstar84]

Some members have retrofitted their controllers with CA inputs - it's not for the faint of heart however. There are inexpensive controller/LCD combos available with programmable features - BMS battery comes to mind.

Yeah I've no where the skill for such tasks and I know i'd end up breaking something rather than modding it.

I'm not that concerned about being pulled over by the police - it's more about liability and coverage: I was hit by a car in a freak accident while riding last October and I went by ambulance to the hospital while my bike went to the police station. Had I been riding something illegal, I doubt the driver's insurance would have covered my losses, medical expenses etc. In your case, a legal ebike may be impracticable and will certainly never do 30 mph.

Yep it would make logically sense that the driver's insurance wouldn't pay out if your bike were illegal... Here in England we don't have medical expenses =/ so people don't mind being as daft as they don't have to pay to recover.

It is voltage that determines speed and amps determines torque. Of course, you need a certain amount of torque to overcome wind resistance and frictional losses to achieve your top speed - and you could limit amps to the point where 48V would be insufficient to attain 30 mph. I'm guessing you'd need at least 700-800W to maintain these speeds on flat ground (maybe more), so at least 15-20 amps? - not exactly legal. Strong pedalling will add 150-250W to the motor, and is good for the heart and soul. Cutting the shunt will reduce amps and can be reversed with a bit of solder, but it involves opening up the controller each time. Far more convenient to regulate the max amps through a programmable controller etc.

Ah this is the kind of information I've been after. So cutting the stunt wouldn't be ideal... a speed controller is what I need. Would I need to mod my controller to use as a three switch speed controller or could I by-pass a cable with it? Looks like you need one made for them; https://zenid10.wordpress.com/category/4-how-to-guide/4-8-controller-modifications/

 

[quackstar84]

You're not getting it. A guy is selling 250w BBS01s in Norway. They're marked 250w 36v 25 amps. Heinzmann were selling 250w geared hub motors with 36v 28 amp controllers. Ezee sell a 500w motor in USA. They sell a 250w one in the UK. Do you know the difference, or shall I tell you? None of those motors burn out.

Some people want an electric moped, others want an electric bicycle. Only OP knows what he wants. I'm nearly 18st and live in a very hilly part of the country with hills as steep as 32% on my regular rides. I'm happy with my "250w" electric bicycle, that hasn't burnt out in nearly 5000 miles.

Ah sorry I forget how to calculate watts. So 36v x 25 = 900watt max?

 

[ddk]

...
Goodness that doesn't come across as aerodynamic... although it will keep you dry.

I live in a rain forest.
Guess what's important to me.
-and-
At the speeds I travel, aerodynamics isn't really an issue.

What battery are you using?

Build my own. I run LiCo in 12S (48ishV) and 15S (60ishV)

So it must acceleration slowly?

Nope. With the 15S battery it takes 20m to accelerate from 0-25 mph (on flat... no wind). Seriously moves if needed.
I prefer the 12S battery. 0-17 mph in 25m. More my (lack of) style.

 

[friendly1uk]

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

^ Very good tool. More use then an adjustable spanner.

If you apply the same power to a typical 15mph 250w geared hub as the 1000w DD the 250w bike climbs better. It also weighs 5kg less and can be cycled around normally without drag from the magnets. This saves power constantly. Even rolling down hills without power the 250w bike gets further. Cycling up then without power puts a huge gap between them. This simple ability to still be used as a normal bike might make DD an outcast before we consider anything further.

The DD could reach 25mph and the Geared hub just 17mph so on the flat as a motorcycle the DD wins. Drop to 10mph and below and the 250w has more grunt. However, as a smaller motor, it will overheat sooner. Should you be climbing mile after mile.

I checked these facts on the simulator I linked to, at the 36V 20A default values present. About as much as a 250w motor wants. Past 48v 20a most won't last long. Maybe 90 seconds up a good grade.


I might be just down the Trent from you. South Derbyshire is a lot different to the north. The city has some long slopes, but in the north you would want a mid drive or motorcycle type build.

 

[Dauntless]

I have no idea what you're reading, but a ketogenic diet literally has nothing to do with that :lol:
( otherwise i'd be fuggin' ripped )

That's what a ketogenic diet literally is all about.

Dude, compared to the way you were, you ARE fuggin' ripped. Start posin'.

 

[E-geezer]

I'm nearly 18st and live in a very hilly part of the country with hills as steep as 32% on my regular rides. I'm happy with my "250w" electric bicycle, that hasn't burnt out in nearly 5000 miles.

Damn, 32%?! That's steep.

 

[Chalo]

I have no idea what you're reading, but a ketogenic diet literally has nothing to do with that :lol:
( otherwise i'd be fuggin' ripped )

Yeah, I gotta say that "before" is who I'd pick for moving furniture, stacking sandbags or working the door at the bar.