Carrera Subway 1 conversion 500w bafang which battery

[Waynejoseph79]

Hello.
This is the first forum I've ever joined. You all seem really helpful from what Ive been reading. Please Help anyone! If some of these topics have already been covered I am sorry.
I'll start from the beginning and apologise now for the length of this and if my plans are complete rubbish but then thats why i came here. Any guidance would be really appreciated.
Since deciding to commute by bike last month, as the wife needs the car now, I found I needed some help getting over the hills on my route.
I live in Wales, UK and there is a VERY steep hill (no clue what %). But to do a 6.5 mile, each way, commute it takes me 40 mins there and an hour to get back( more when the wind is up, nearly always). I am quite fit but a large guy. 6' 4" tall and 16 stone. Due to the hills I HAVE to get off and walk it up for a good 15 mins of the journey.

After reading lots and lots of very bad reviews about pre built bike's and how they use very cheap base bikes and components, I have decided to buy a new bike and convert it.

Here's my plan.

Buy a new Carrera Subway 1 with mechanical disc brakes.
Fit 500w bafang mid drive motor with 48v 10 ah lithium battery.

My questions are:-
How good a hill climber is a mid crank vs say big bear hub motor from whoosh?

Is this the best/safe battery to use? The kit and battery would be coming from whoosh bikes and its the only 48v they do / have in stock. ( I thought 10ah was quite low for 48v, as a 36v at 15 ah produces more watts) Is that right?........

Has anyone had legal problems riding a 500watt motor if ridden sensibly. Im not a speed freak I just need a good boost with the gradients I have around me. I understand the need to not have cycles going at 40MPH but cutting the ability to climb in order to control the speed seems unfair.
I don't understand the law's regarding this as I would have thought most of us want more power for getting UP the big hills rather than speed. As a 250watt motor cuts out at 15 mph and any able bodied folk can easily ride at that sort of speed with no assistance, I cant see the point of one if (from what Ive read) these smaller motors cant get you up or maintain speed on big hills.
Thanks for any help received.

 

[anotherkiwi]

As a 250watt motor cuts out at 15 mph and any able bodied folk can easily ride at that sort of speed with no assistance, I cant see the point of one if (from what Ive read) these smaller motors cant get you up or maintain speed on big hills.

I thought that too until Saturday when I rode up a 5% gradient which is about 3 km long at 25 kph without breaking a sweat. The 250W motor was drawing between 250 and 500W all the way up and at the top the motor was as cool as a cucumber.

 

[soundwave]

my haibike flys up hills with the bosch motor on it 350w with dongle fitted and can do about 30-35mph if peddling hard and can get about 28 miles in turbo mode on it.

had police cars behind me and pass and not been a problem with the dongle on it as you cant really see it and can be removed in seconds anyway.

 

[Benjahmin]

I too live in Wales, Ceredigion. I also thought that 250watts didn't sound like much. But I converted my hybrid anyway. It has a 250w, 36v front hub ezee motor and I haven't had to get of on a hill since. The wattage rating is misleading and is mearly the maximum continuous wattage the motor will take without overheating. It will actually draw much more.
However my kit is limited to 15.5mph and the bike is now so heavy riding without assistance is not really an option.
Needs differ, I'm 61 and cycle for pleasure, I don't have to commute.

I would say that if you are a fit, regular cyclist then a legal e-bike is going to be too slow for you. Sports cyclists regularly zip past me on the flat, I do tend to see them again though at the next hill!

 

[soundwave]

i can over take carbon fibre racing bikes on mine with not much effort.

its funny as hell watching them try keep up with me fing this and that lol

 

[Deleted member 4366]

I would get a battery with branded cells. They perform much better than the unbranded ones. Eclipse have a 48v 11.6ah one with Samsung cells or you can get your whole kit from BMSBattery, who also sell a very nice hub motor kit. You an get the 48v 11.6ah battery with Panasonic cells that includes a 20 amp sinewave controller. Add a 48v Q128 motor or 500w BPM and you have a real hill-climbing kit. The Q128 is quite small for its 800w rated power. It's the same size as a normal 250w motor, so nobody would ask about its legality, especially if you remove the removable label.

 

[Waynejoseph79]

my haibike flys up hills with the bosch motor on it 350w with dongle fitted and can do about 30-35mph if peddling hard and can get about 28 miles in turbo mode on it.

had police cars behind me and pass and not been a problem with the dongle on it as you cant really see it and can be removed in seconds anyway.

Thanks for the replies all. What is a dongle? Flash drive with some sort of hack on it? Sorry.

 

[Waynejoseph79]

I thought that too until Saturday when I rode up a 5% gradient which is about 3 km long at 25 kph without breaking a sweat. The 250W motor was drawing between 250 and 500W all the way up and at the top the motor was as cool as a cucumber.

Thanks, do you think 250w is enough for 10% hills and more? I'd like to stay legal but if it wont do want I need it too theres just no point.? ta

 

[Waynejoseph79]

I too live in Wales, Ceredigion. I also thought that 250watts didn't sound like much. But I converted my hybrid anyway. It has a 250w, 36v front hub ezee motor and I haven't had to get of on a hill since. The wattage rating is misleading and is mearly the maximum continuous wattage the motor will take without overheating. It will actually draw much more.
However my kit is limited to 15.5mph and the bike is now so heavy riding without assistance is not really an option.
Needs differ, I'm 61 and cycle for pleasure, I don't have to commute.

I would say that if you are a fit, regular cyclist then a legal e-bike is going to be too slow for you. Sports cyclists regularly zip past me on the flat, I do tend to see them again though at the next hill!

Thanks for the reply. I dont think I've ever struggled to make a decision in all my life.

Mid crank vs hub, legal or not which battery from where and who has what in stock....For me this is a lot of money to spend so I need to get it right. I just keep going back and fore.

d8veh has suggested the q128 which i'd not heard of and now that looks like the way to go but i like the idea of using the bikes gears to keep the motor in ideal rpm.

back and fore........

 

[Waynejoseph79]

I would get a battery with branded cells. They perform much better than the unbranded ones. Eclipse have a 48v 11.6ah one with Samsung cells or you can get your whole kit from BMSBattery, who also sell a very nice hub motor kit. You an get the 48v 11.6ah battery with Panasonic cells that includes a 20 amp sinewave controller. Add a 48v Q128 motor or 500w BPM and you have a real hill-climbing kit. The Q128 is quite small for its 800w rated power. It's the same size as a normal 250w motor, so nobody would ask about its legality, especially if you remove the removable label.

Thanks you've just given me even more choices. What to do....

 

[trex]

before you go ahead with ordering, note that the Carerra Subway has the right gear shifter integrated with the right brake lever. You will lose the front derailleur, so replacing the left integrated lever with a sensored brake lever is not a problem but you have to keep the Subway right brake lever. One more thing, there are two 500W BBS02, 36V 25A which is optimized for climbing hills and 48V 18A optimized for speed. Both will draw as much as 900W when pushed hard. You will need a battery that can support that much power for 10 minutes, most likely with Samsung 29E cells.

 

[Waynejoseph79]

Thanks for that. I think id go for the 36v 25 a then.
How many ah would the battery need to be please? 36v 15ah enough?
Thanks trex

 

[Deleted member 4366]

i like the idea of using the bikes gears to keep the motor in ideal rpm.

back and fore........

It's a lot easier to use the motor to keep the bikes gears in the optimum RPM. The idea that you can get better efficiency by keeping a crank-drive motor at the ideal rpm is a fallacy. You won't see a significant difference in practice. There's not a single test report that shows the crank-drive more efficient during a comparison. The only test reports I've seen show the opposite, which is backed up by my own trials.

 

[RobF]

Either a crank or hub 500w motor will give you plenty of poke.

Don't worry about top speed, bowling along at 15mph-ish will get your 6.5mile commute done in about 30 minutes.

You would have to go much faster to get a useful time saving over such a short distance.

That would mean a derestricted bike and hammering along at 20mph+ obviously under power which might draw unwanted attention.

Particularly so as you would be doing that on the same route twice a day.

Assuming you haven't yet bought the Carrera, I would look closely at the Oxygen MTB.

The more powerful one is currently on offer through dealers at £1,200 - a discount of £500.

It has a powerful hub motor, will do 20mph+ if you choose to, and has a 13ah battery.

Easy enough to trick it up for commuting with some guards, seat post mounted rack (if needed) and battery lights for the winter.

By the time you've bought a kit and battery for the Carrera, there won't be a lot in it, money wise.

And you will have a bike which would be great fun to ride at the weekends.

http://www.syebc.co.uk/bikes/oxygen-13ah-mtb

 

[Waynejoseph79]

It's a lot easier to use the motor to keep the bikes gears in the optimum RPM. The idea that you can get better efficiency by keeping a crank-drive motor at the ideal rpm is a fallacy. You won't see a significant difference in practice. There's not a single test report that shows the crank-drive more efficient during a comparison. The only test reports I've seen show the opposite, which is backed up by my own trials.

Thanks for that. I suppose there's no chance of me messing up my chain and gears either. Cheers.
Think I'm going for the hub.

 

[soundwave]

Thanks for the replies all. What is a dongle? Flash drive with some sort of hack on it? Sorry.

https://www.badassebikes.com/

 

[Waynejoseph79]

Either a crank or hub 500w motor will give you plenty of poke.

Don't worry about top speed, bowling along at 15mph-ish will get your 6.5mile commute done in about 30 minutes.

You would have to go much faster to get a useful time saving over such a short distance.

That would mean a derestricted bike and hammering along at 20mph+ obviously under power which might draw unwanted attention.

Particularly so as you would be doing that on the same route twice a day.

Assuming you haven't yet bought the Carrera, I would look closely at the Oxygen MTB.

The more powerful one is currently on offer through dealers at £1,200 - a discount of £500.

It has a powerful hub motor, will do 20mph+ if you choose to, and has a 13ah battery.

Easy enough to trick it up for commuting with some guards, seat post mounted rack (if needed) and battery lights for the winter.

By the time you've bought a kit and battery for the Carrera, there won't be a lot in it, money wise.

And you will have a bike which would be great fun to ride at the weekends.

http://www.syebc.co.uk/bikes/oxygen-13ah-mtb

Thanks Rob F
looks nice but ive got a budget of £1000 max. Thats pushing it. If I could stretch to that I would consider it. Thanks though. I figure £600-£700 for kit and £300 ish for the bike.

 

[soundwave]

i get the oxygen for the sake of 200 quid and using a diy kit

 

[trex]

the Q128H is a very good kit. You won't pull wheelies with it but it gives a nice, gentle and persuasive push - be careful with power consumption, it will pull 800W from your battery! Bmsbattery sells the kit (48V 8AH downtube battery + everything you need) in a 26" rim for about $370. Top speed 23mph. If you want to try it, go visit Woosh in Southend. They have a test bike fitted with both crank drive and Q128H and two batteries, two throttles and two controllers. It rides very well. You can alternate between the two drive systems or use both.

 

[Deleted member 4366]

IMHO the 8AH battery is a false economy. For me it has to be 11.6ah (Panasonic, Sony or Samsung) or nothing. It's well worth paying the extra. I have one of the unbranded 10ah ones. The sag is a lot worse and the range a lot less. For a 20A controller, you need good cells.