beginner

john1234567

Finding my (electric) wheels
Mar 7, 2017
12
2
93
uk
Hello,

Cycle every day to work but there is a very large hill that I have to ascend in either direction and after a hard day at the office and at the end of the journey I have to do the Matterhorn and I just don't like it. My commute is about 15 miles round trip.

So my question is what would be the best starter kit for converting my old bike to electric rear wheel.

I'm a very good engineer so can make stuff work without being spoon fed or when things aren't ideal I know what to do. So I guess what I'm looking for is to decide what my specifications should be. I just want to be able to climb the hill and I can peddle for the rest. Of course I also want quality and reliability.

I've seen the kits on eBay ranging from £200 to £600. I could build my own from parts.

Are the brushless hub motors the best thing these days?
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
Brushless is the way to go and is the standard today for hubs, add a sinewave controller and you get a pretty quite set up.
Alternatively you can add a crank drive like the BBS01B from eme3v,Woosh, Eclipse or Brighton e bikes.

Building you own kit isn't always cheap but gives you a few more options as mostly you have to look to Chinese vendors for the parts, they are relatively cheap but you have to factor in air freight and duty and batteries can be got from the UK.

For hill climbing look for a hub drive with low rpm 201 or 260 would be all right and consider 48v over 36v as torque and speed will generally be 25% more.
How heavy are you because depending on your weight you could get away with a lighter motor.
 

john1234567

Finding my (electric) wheels
Mar 7, 2017
12
2
93
uk
I'd have to estimate my weight as I don't weigh myself much. I reckon a fairly average 12 stone would be a good guess.

I googled the BBS01B but there are two things which don't seem great about that kit. Primarily the fact that they're experiencing supply problems so aren't able to offer the kits currently. It also seems to involve many more moving parts compared with a brushless motorised rear wheel.

It would be great to see links to kits people have already bought which would be good for what I'm trying to do. It is a very big hill so I'd rather overspecify as it would be a pointless exercise if the motor wasn't powerful enough.
 

john1234567

Finding my (electric) wheels
Mar 7, 2017
12
2
93
uk
I'm ok with messing around. My bike is 25 years old and has been rebuilt several times during that period. I guess there's no point in having a conversion forum if people only recommend replacing the entire bike.
 

Ultrafunkula

Pedelecer
Mar 18, 2011
168
114
I'm ok with messing around. My bike is 25 years old and has been rebuilt several times during that period. I guess there's no point in having a conversion forum if people only recommend replacing the entire bike.
Remember there is a fair bit of drag on a hub motor compared with crank drive, I've had 2 hub motor units , one was an A2B metro which is geared hub , other was crystalite unit ,when battery is flat or switched off its like riding with brakes on or like permanently climbing the Matterhorn .
 
D

Deleted member 4366

Guest
Remember there is a fair bit of drag on a hub motor compared with crank drive
That's very misleading to gneralise like that based on a couple of exceptional cases. How much drag is on this typical Chinese geared hub-motor? Many geared motors have the clutch outboard of the gears so that the only part turning when free-wheeling is the hub, just like a normal bike, so no drag at all.

At only 12 st, I'd say that a hub-motor would be much more suitable for OP than a crank-drive. You get a more relaxing ride (less gearchanging, banging and crashing of gears) and they're cheaper. Basically, any 36v kit should be a good solution, but Ultrafunkuls's advice is valid regarding the cheap big direct drive hub-motor kits that you see on Ebay. Keep away from them.

Reliability is more down to installation than the kits themselves, though you have to think about water-proofing. I ride my bikes in the rain and have never had a problem, but I've seen a lot of motors and a few batteries, LCDs and connectors with water in them.

There's quite a lot to consider when choosing a kit, though just about any one would be better than not having one. I would recommend getting one with a LCD. The cheaper rear kits have free-wheel gears, which means a max of 7 speeds and low gearing unless you want to spend an extra £20 or more on a DNP gearset with 11T top gear.

If you want to get your bike just how you want it, you have to mix and match components/modules and pay a bit more. You have to be realistic though, so unless you want to do that or get the very cheapest solution, it can make a hard case to justify a kit when you have the Cyclamatic CX3 at £680.

http://www.thesportshq.com/cyclamatic-cx3-pro-power-plus-alloy-frame-ebike.aspx
 
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anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
7,845
5,786
The European Union

damian

Pedelecer
Sep 16, 2015
118
58
59
Belfast
It is easy to justify if you live in Ireland - 1200€ delivery fee puts that bike at 2015.99€... :eek: Another reason to smuggle it in from Northern Ireland where shipping is only 5.99€
Is that such a bad idea?
Get it sent to someone here (offering my address if you want it), then get the train up and back down again. Take advantage of the strong euro!

Sent from my E2303 using Tapatalk
 
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john1234567

Finding my (electric) wheels
Mar 7, 2017
12
2
93
uk
That pre-converted electric bike looks very tempting actually.

I know I said I thought I'd be ok converting my old one, but my old bike isn't in fantastic shape anyway so I could just scrap it and go for the electric option.

The components look cheap on that bike, but I guess over time you could upgrade.
 

john1234567

Finding my (electric) wheels
Mar 7, 2017
12
2
93
uk
I wanted to buy the eBike linked to above but found it isn't back in stock for a long time. I think they quoted end of May or something like that.

I looked around at some of the other bikes and there aren't any which are as cheap as the CX3. I liked the idea of a lightweight aluminium frame, disc brakes and suspension forks at the price.

However, since the CX3 wasn't available I had to do more research to try and find out what I wanted and started to get worried that the 250w motor isn't up to the job. I read a review of a 250w bike (it might have been the CX3 but can't remember) and the guy said it struggled on hills. Given that I wanted an electric bike specifically for hills it became obvious that the 250w motor wasn't going to cut the mustard.

So I went for the 1000w motor. That also requires a step-up in battery voltage to the 48v battery and I recognised from other themes I'm more familiar with that the requirement for a stronger battery meant the 1000w motor was in a different class to the lower powered 36v 750w kits.

The legality of a kit like this is questionable but it can be legally sold as long as it is restricted to 15.5mph. I'm actually fine with that speed and won't be de-restricting it. My reason for buying the more powerful kit was to ensure that it could deliver within the legal limit under less than ideal conditions. i.e. on a very steep incline I am hoping for 7+ mph. I read that the 250w kits aren't really up to the job.

I'll add more details when I've tried it out.

ebike.jpg
 

john1234567

Finding my (electric) wheels
Mar 7, 2017
12
2
93
uk
I did do some improvements to my existing bike in preparation for fitting the kit. As mentioned above, I wasn't happy with the condition of my bike.

I had the headset changed and new brake pads fitted. It rides a lot better now and is ready for the upgrade to electric.
 
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john1234567

Finding my (electric) wheels
Mar 7, 2017
12
2
93
uk
Price though... I think that's the difference. The CX3 is more than a £1000 pound cheaper than any of the KTMs I could see the price of.

As with any other sort of electrical appliance there are other variables which will affect the overall performance of the product. So both would be 250w rated but there will be other differences elsewhere which mean the guy who reported in a review that his bike struggled with some hills and you who say you've no problem with any hill are both correct at the same time. I definitely can't afford a KTM.
 

john1234567

Finding my (electric) wheels
Mar 7, 2017
12
2
93
uk
And I should add, I'm glad that your bike is capable of the sort of performance I'm hoping to get from my kit. If it's the sort of thing you can do with an eBike then I'm reassured that I've made the right decision to invest in this technology and that I've not wasted my money.
 

Woosh

Trade Member
May 19, 2012
20,379
16,876
Southend on Sea
wooshbikes.co.uk
I'm actually fine with that speed and won't be de-restricting it.
Hello John,
The motor you bought is a gearless motor, AKA DD (direct drive) motor.
They are great when you ride at 25+mph but consume a lot more energy at speed below 25mph compared to crank drives or hub motors with internal gearbox.
There are good geared hub motors on the market. I sell three models, the MXUS XF08C for riders up to 14 stone, Bafang SWX02 up to 16 stone and Bafang BPM above 16 stone. The BPM is of course the most powerful of the three. It has more torque than 1000W DD motors up to about 15mph. If you only want to ride around 15mph, the BPM is a better choice, it consumes less energy than DD motors.
 

Wicky

Esteemed Pedelecer
Feb 12, 2014
2,823
4,011
Colchester, Essex
www.jhepburn.co.uk
Price though... I think that's the difference. The CX3 is more than a £1000 pound cheaper than any of the KTMs I could see the price of.

As with any other sort of electrical appliance there are other variables which will affect the overall performance of the product. So both would be 250w rated but there will be other differences elsewhere which mean the guy who reported in a review that his bike struggled with some hills and you who say you've no problem with any hill are both correct at the same time. I definitely can't afford a KTM.
I got mine specifically to deal with hills and as it was an ex-demo bike got it at a very affordable price direct from UK KTM distributer. Even managed to test ride a similar model at hilly Redbridge circuit (road & off-road) against other bikes in which it outshone the others.

Here's a few more reviews on what the bike is capable of

http://www.pedelecs.co.uk/forum/threads/ktm-erace-p-first-impression-review.15192/

 
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D

Deleted member 4366

Guest
However, since the CX3 wasn't available I had to do more research to try and find out what I wanted and started to get worried that the 250w motor isn't up to the job. I read a review of a 250w bike (it might have been the CX3 but can't remember) and the guy said it struggled on hills. Given that I wanted an electric bike specifically for hills it became obvious that the 250w motor wasn't going to cut the mustard.
This is the problem with internet research. You have no idea of the context, experience or bias of whoever writes that stuff. My £125 250 watt motor kit will climb hills that your motor can only dream of, and there's plenty of other options

We warned you against getting one of those big DD motors. Let's see how you get on with it. Please keep us informed how you get on.
 
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Woosh

Trade Member
May 19, 2012
20,379
16,876
Southend on Sea
wooshbikes.co.uk
people see a 1000W motor as naturally more capable than a 250W one. Who can blame them?
It's difficult to get the point across that 1000W DD motors are only good for very limited circumstances, high speed (20+mph) and low gradient (less than 5%).
 
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Tabs

Esteemed Pedelecer
Jul 1, 2016
279
132
64
Scotland
I nearly made the mistake of getting a big 750 or 1000w motor but the advice I got from here convinced me that the 250w geared set up would be best for my needs and guess what......... It is!! It's powerful enough to get me up any hill(with me putting in a bit of effort)and On the lowest setting I probably would get over 40 miles range,all this from a 36v 250w set up can't be bad especially as I'm over 20st.