How do I get increased power

[ACG]

Hi! First of all ... I know next to nothing about the technicalities of ebikes ... so the advice I am looking for is more along the lines of ‘what do I need done, who should I go to to get this done (Glasgow area), and how much should I expect to pay’. PLEASE!
I have recently bought a junior carrera vengeance e bike. I bought a junior bike, because I am just less than 5 foot tall ... so needed a smaller bike. Unfortunately (and very unfortunately for my husband who chose to point this point this out ;-) ) ... I am far from junior weight!
The power of the bike is very poor. I have another ebike with much much stronger power ... it’s no where near a match. I assumed it was the battery ... but my husband kept saying ‘motor’ ... so I’ve finally realised that there is a ‘motor’ on an ebike as well as the battery! (You can see how little I know!)
When I looked up the battery its in Wh ... it’s not in Volts and Watts as my other bike (which is 36V 16A).
I can now look up and see that my carerra bike is a Phylion 317 Wh battery and the motor is a suntour rear hub motor 250Wh.
HELP please. It’s a great bike height wise for me ... but without more power ... it’s barely doing it’s job as an ebike. My other bike is less suitable height wise ... but ... the power is much better.
Range isn’t too too important to me ... I’m not likely to go much beyond the 30 mile range ... but I might if the bike was more useable for me.
THANKS in advance for helping guide me!

 

[sjpt]

That Suntour model on some Carreras is notorious for not working properly, in particular cutting out. Is it possible that it has just cut out and not doing anything as an ebike?

It is the motor that determines the power, as long as the battery is capable. Your other bike is probably 250w as well (more than that is not legal without lots of complications), but not all nominally 250w motors are alike. However, the Suntour should be enough power-wise for most purposes.

The Wh on your old bike is 576 (36*16). This will mainly affect the range (how long you can draw the power for), not directly the power. The Carrera battery won't give you 30 miles except with very light use.

If the bike is very new it may be worth considering returning it.

 

[ACG]

That Suntour model on some Carreras is notorious for not working properly, in particular cutting out. Is it possible that it has just cut out and not doing anything as an ebike?

It is the motor that determines the power, as long as the battery is capable. Your other bike is probably 250w as well (more than that is not legal without lots of complications), but not all nominally 250w motors are alike. However, the Suntour should be enough power-wise for most purposes.

The Wh on your old bike is 576 (36*16). This will mainly affect the range (how long you can draw the power for), not directly the power. The Carrera battery won't give you 30 miles except with very light use.

If the bike is very new it may be worth considering returning it.

That Suntour model on some Carreras is notorious for not working properly, in particular cutting out. Is it possible that it has just cut out and not doing anything as an ebike?

It is the motor that determines the power, as long as the battery is capable. Your other bike is probably 250w as well (more than that is not legal without lots of complications), but not all nominally 250w motors are alike. However, the Suntour should be enough power-wise for most purposes.

The Wh on your old bike is 576 (36*16). This will mainly affect the range (how long you can draw the power for), not directly the power. The Carrera battery won't give you 30 miles except with very light use.

If the bike is very new it may be worth considering returning it.

Thanks so much ... that is a great help. The motor does work but at a much lower level than I expected. If it’s a legal max at 250 ... it should be just as powerful as my other bike ... just shorter range. I’d have gone back to the shop (cycle republic) ... it’s less than 2 months old ... but I’ve noticed the two shops in Scotland have just permanently closed. I gather they are owned by the same company as Halfords ... so I’m not sure if I can have an arrangement to go there.
Thanks so so much for your reply ... at least I can contact CR with a level of confidence of what the issue is. A big thanks!

 

[flecc]

If it’s a legal max at 250 ... it should be just as powerful as my other bike ...

That isn't actually the case, the 250 watts is just a legal nominal power stated by the supplier as the EN15194 technical standards allow. The actual maximum power of nominally 250 watt e-bike motors mainly varies between 300 and 600 watts, so varying very widely.

In addition the motor winding and any internal gearing also affects the power, more accurately perceived as the torque which is the pulling power.

It's one of the reasons that we usually advise to always try before buying.

Halfords have sold Cycle Republic to Pure Electric, see this link

Hopefully Pure Electric will support you.
.

 

[Sturmey]

.....The motor does work but at a much lower level than I expected. If it’s a legal max at 250 ...

Hi. I think that particular bike has a 'torque sensor', which can be unsatisfactory for some people, as the power output is a multiple of your pedaling input and if you cant keep a certain amount of pressure on the pedals, the power output is poor. I am a weak cyclist and cannot keep up the pressure required to go fast for any length of time. You may need a bike with either a cadence sensor or a throttle.

 

[ACG]

That isn't actually the case, the 250 watts is just a legal nominal power stated by the supplier as the EN15194 technical standards allow. The actual maximum power of nominally 250 watt e-bike motors mainly varies between 300 and 600 watts, so varying very widely.

In addition the motor winding and any internal gearing also affects the power, more accurately perceived as the torque which is the pulling power.

It's one of the reasons that we usually advise to always try before buying.

Halfords have sold Cycle Republic to Pure Electric, see this link

Hopefully Pure Electric will support you.
.

Thanks ...all very useful. I agree ... it would have been much better to have tried before I bought ... but it wasn’t an option.
Thanks for the link for Pure Electric ... it had looked like the Glasgow and Edinburgh shops were closed permanently .. but it looks like they might remain . I’ve written to CR via their website ... so hopefully they’ll get back to me and give me information.
I don’t even mind too much if I have to pay a bit to get a better motor if that’s what it takes ... I just want a bike with more power.
Thanks

 

[ACG]

Hi. I think that particular bike has a 'torque sensor', which can be unsatisfactory for some people, as the power output is a multiple of your pedaling input and if you cant keep a certain amount of pressure on the pedals, the power output is poor. I am a weak cyclist and cannot keep up the pressure required to go fast for any length of time. You may need a bike with either a cadence sensor or a throttle.

R

Thanks ... once I get to speak to someone I can ask about that.

 

[Nealh]

The power isn't down to the motor as even a 250w hub can take about 1000w for short periods, the power is determined by the motor controller current and the battery continuous output to deliver it.
The Suntour system you can't buy or upgrade with generic parts unless you replace all but the hub, it might be possible to carry out a shunt mod to increase the current.

 

[scott gaza]

The motor winding's are likely different with the more perceived power torque on the low rpm wheel is there any way you can swap them over? or it could be down to the controller being limited and the battery only being half the size . What is the other bike you have?

 

[ACG]

The power isn't down to the motor as even a 250w hub can take about 1000w for short periods, the power is determined by the motor controller current and the battery continuous output to deliver it.
The Suntour system you can't buy or upgrade with generic parts unless you replace all but the hub, it might be possible to carry out a shunt mod to increase the current.

Thanks for the very useful information ... as someone who knows zero about this I would have to get someone else to do this for me ... am I likely to be able to find a provider in the Glasgow area that could do that for me??? (Very roughly) ... how much would that cost?? Thanks?

 

[ACG]

The motor winding's are likely different with the more perceived power torque on the low rpm wheel is there any way you can swap them over? or it could be down to the controller being limited and the battery only being half the size . What is the other bike you have?

 

[ACG]

My other bike is an axcess Shetland. It has the type of battery that of the type sometimes referred to as silver fish. The battery on the carerra is phylion.

 

[sjpt]

That isn't actually the case, the 250 watts is just a legal nominal power stated by the supplier as the EN15194 technical standards allow. The actual maximum power of nominally 250 watt e-bike motors mainly varies between 300 and 600 watts, so varying very widely.

In addition the motor winding and any internal gearing also affects the power, more accurately perceived as the torque which is the pulling power.

It's one of the reasons that we usually advise to always try before buying.

Halfords have sold Cycle Republic to Pure Electric, see this link

Hopefully Pure Electric will support you.
.

Absolutely. Even though there are differences in nominal 250w motors (as you said and I had said) I still think it sounds as if something is wrong rather than just a weaker motor: OP says 'it’s barely doing it’s job as an ebike'. We've had lots of posts on cutout issues, but I don't remember any complaints the motor was particularly weak ... I've even a vague recollection (which could be wrong) of somebody commenting that it was reasonably strong.

As you say, lets hope that Pure Electric support OP properly. I wonder if there are any forum members from around Glasgow with a Carrera Suntour bike; maybe they could get together(ish) and compare the power of the two.

 

[scott gaza]

Hi the 20" wheel would only give you around 30% more torque but less speed form the exact same motor compered to a 26" wheel. You're best bet would be to return it if you can stating its not fit for propose. Sound like they have limited the bike to 7amp max due to being a junior model but i dont know for sure! https://www.halfords.com/bikes/kids-bikes/carrera-vengeance-junior-mountain-bike---26in-wheel-203894.html and buy a kit like https://wooshbikes.co.uk/cart/#/product/uid-192-xf07kit-13ah/xf07-front-hub-kit-with-13ah-battery or cheaper option https://yosepower.com/collections/electric-bike-conversion-kit/products/36v-350w-rear-motor-kit-with-36v12-5ah-battery or https://wooshbikes.co.uk/?secondhand

 

[ACG]

Hi the 20" wheel would only give you around 30% more torque but less speed form the exact same motor compered to a 26" wheel. You're best bet would be to return it if you can stating its not fit for propose. Sound like they have limited the bike to 7amp max due to being a junior model but i dont know for sure! https://www.halfords.com/bikes/kids-bikes/carrera-vengeance-junior-mountain-bike---26in-wheel-203894.html and buy a kit like https://wooshbikes.co.uk/cart/#/product/uid-192-xf07kit-13ah/xf07-front-hub-kit-with-13ah-battery or cheaper option https://yosepower.com/collections/electric-bike-conversion-kit/products/36v-350w-rear-motor-kit-with-36v12-5ah-battery

 

[ACG]

Thanks ... that’s very helpful. I’m waiting to hear back from Cycle Republic first ... and at the moment the kit suppliers are out of stock ...but that gives me a good option. Thank you.

 

[scott gaza]

you must have a case in you're favor they should not be able to sell the shop without giving you pre warning. dont let them fob you off with anything less than a full refund! PS; LOOK UP
Carrera Crossfire e it has very bad reviews

 

[ACG]

you must have a case in you're favor they should not be able to sell the shop without giving you pre warning. dont let them fob you off with anything less than a full refund! PS; LOOK UP
Carrera Crossfire e it has very bad reviews

Thanks Scott, I am hoping between Halfords and Pure Electric there will be one of them to pick it up. If not I bought it on a credit card ... so could pursue that. I bought the carerra specifically because it had a junior size ... and at my height I needed a bike at the right height. At least now I have more knowledge of what to do. Thanks so much

 

[scott gaza]

just watch out you're rights diminish fast after the first 28 days so you would need to play on the fact of there breach of contract for lack of support in physical terms ie; no shop! and play on that you would have returned it straight away but you couldn't because look down, no shop, no internet access ..........it would be a shame to have to replace things just to get something useful at the end off the day .

 

[ACG]

just watch out you're rights diminish fast after the first 28 days so you would need to play on the fact of there breach of contract for lack of support in physical terms ie; no shop! and play on that you would have returned it straight away but you couldn't because look down, no shop, no internet access ..........it would be a shame to have to replace things just to get something useful at the end off the day.