Cheap Chinese vs Cheapish Conversion?

Clockwise

Esteemed Pedelecer
Jun 28, 2013
438
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The more I look at the cheaper end of ebikes the more I notice the conversion kits usually have the same 8fun motors in them and similar controls.

At the moment the only advantage/disadvantage seems to be that the battery might not be as well placed as on one that comes ready made. I would also more than likely be looking at a front hub motor instead of a rear hub motor if I build myself, I can't really tell what advantages that could have for either of them apart from when I have to service it the gears and things won't be in the way.

Is just another idea as I would still need a bike that would suit conversion, any tips/advice?
 

trex

Esteemed Pedelecer
May 15, 2011
7,703
2,671
Wiring is the most difficult aspect when doing a conversion.
Motor cables, battery cables, sensor cables - they are all too long most of the time.
The other issue is wheelset. If you buy a motor wheel, the rim and spokes don't match with the other wheel. Lacing the wheel yourself is also a big challenge.
If you have a 500W motor, it's sensible to have hydraulic brakes then sensor for hydraulic brakes is another challenge. Battery housing: it will certainly be less safe than ready made jobs, no matter how hard you try.
The only easy conversion is the 8-Fun crank drive kit.
 

Alan Quay

Esteemed Pedelecer
Dec 4, 2012
2,351
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Devon
The major advantage of conversion is that you can get exactly what you require. The major difficulty is deciding what you want.

Before considering converting, you need to have an idea of the following parameters:
Range, speed, power, terrain, budget, style, luggage, weight(yours), weight(bike), special requirements. There are others that I have missed.

All that said, a BPM/CST 250 watt/36v and a 20 ah lithium battery on a half decent mountain bike will probably set you back about £600-700, and go 30-40 miles averaging 16 mph.

Assuming you own some basic tools and have learned to use them, then conversion is really not that hard. If you are the 'DIY type' it can be very satisfying.

From a purely financial point of view though, I don't think there is much in it.
 

jackhandy

Esteemed Pedelecer
May 20, 2012
1,820
323
the Cornish Alps
The major advantage of conversion is that you can get exactly what you require. The major difficulty is deciding what you want.

All that said, a BPM/CST 250 watt/36v and a 20 ah lithium battery on a half decent mountain bike will probably set you back about £600-700, and go 30-40 miles averaging 16 mph.
First paragraph's spot on, Mike: That should be the mantra for all aspiring ebikers, whether self-building or buying ready-made.

My first build, 12 months ago, was an 8fun kit on a Carrera Kraken:
Bike £ 70 on ebay
Kit. 450 from 8fun uk
2nd battery borrowed from the missus' bike 'cause she won't miss it...

My current requirements, based on 12 months' sheer enjoyment:

More grunt up hills
60 miles potential range (as I have now)
Rear wheel drive

So, I've looked at what's on offer, ready-built, and can't realistically see me having change from £2,000, which would have been my top budget if I hadn't been chucking money down a black hole lately.

The obvious course now is a build - whether a kit will do it, or a scratch-build, I don't know. I've always been tempted by the CST, but they don't seem to all be equal, somehow. Time to start researching all over again, methinks.
 

Sacko

Esteemed Pedelecer
Aug 23, 2011
281
13
Get a direct drive motor and use regen.
 

Clockwise

Esteemed Pedelecer
Jun 28, 2013
438
53
Get a direct drive motor and use regen.
Links?

I'm still new to all this stuff so learning.

Also I see lots of custom builds have "battery bags" but the kits come with the bottle shape battery's or pannier battery's? Am I missing something?
 

Alan Quay

Esteemed Pedelecer
Dec 4, 2012
2,351
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Devon
As for battery placement, here are some things I've seen done:

1. Dedicated rear rack, something like this: Rack For Our 03 and 05 Battery Case - BMSBATTERY
2. A D8veH Special football boot bag:http://www.pedelecs.co.uk/forum/electric-bicycles/13226-new-build-carrera-kracken-conversion.html
3. A battery in a toolbag, mounted on an ordinary rack: Claud Butler - Pedelecs Electric Bike Showcase
4. Bottle type battery, mounted on the downtube.
5. frame bag/custom box: http://www.pedelecs.co.uk/forum/electric-bicycles/13813-cst-its-all-working-13.html
6. Strapped underneath the top tube.
7. In a basket on the handlebars (I wouldn't, but I guess it depends on weight).
8. In a backpack.
9. In soft/hard panniers

All have their strengths/weaknesses. Anyone think of anymore options?
 

jackhandy

Esteemed Pedelecer
May 20, 2012
1,820
323
the Cornish Alps
As for battery placement, here are some things I've seen done:



All have their strengths/weaknesses. Anyone think of anymore options?
Battery inna backpack with a longish cable - quite popular over the pond I believe: BUT you must remember to unplug yerself before walking away! READ THE DAMN POST PROPER BEFORE PONTIFICATING, JACK. Sorry Mike :eek:

I'm probably just being an old woman again (seems to be that or offensive know-all, according to some) but those forks look a tad weedy for a front-wheel motor to me - IMHO, of course.
 
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Alan Quay

Esteemed Pedelecer
Dec 4, 2012
2,351
1,076
Devon
.....Battery inna backpack....
I assume it makes for more nimble off road handling, but that's just a guess. Certainly not an option I've ever seriously considered for one of my bikes - just too weird.

....READ THE DAMN POST PROPER BEFORE PONTIFICATING, JACK. Sorry Mike :eek:......
No need to be sorry dude.

.....those forks look a tad weedy for a front-wheel motor ...
Are you talking about the cruiser bike on the 8fun website? If so then perhaps, but they could well be made of steel. You are probably too young to remember, but it was a popular material for bicycle frames back in the 19th/20th century ;-)
 
D

Deleted member 4366

Guest
Dropped an email to the people on that site, see how much it is to get some stuff shipped as it seems crazy cheap before shipping.
To check the shipping price, you have to register with the site and then go through the check-out process, You can stop before you have to pay. I did this foe you to find that the shipping cost is $85 to bring the total to $100 or £67. If you buy it with a battery or anything else, it works out a lot cheaper.
 

skidders

Finding my (electric) wheels
Jun 7, 2013
21
0
A, A
To check the shipping price, you have to register with the site and then go through the check-out process, You can stop before you have to pay. I did this foe you to find that the shipping cost is $85 to bring the total to $100 or £67. If you buy it with a battery or anything else, it works out a lot cheaper.
love your quote at the bottom dude totally unrelated to the subject but love it
 

Clockwise

Esteemed Pedelecer
Jun 28, 2013
438
53
To check the shipping price, you have to register with the site and then go through the check-out process, You can stop before you have to pay. I did this foe you to find that the shipping cost is $85 to bring the total to $100 or £67. If you buy it with a battery or anything else, it works out a lot cheaper.
I'm not totally sure about the postage options but doing the same I had a look and it would seem I can get all the bits I need and spare brake levers and things to last me years for £300-350. Put that with the bike cost and it will still be cheaper than the ready mades from china even if a bit more effort.

Going to need a good sit down to pick a bike.
 

mountainsport

Esteemed Pedelecer
Feb 6, 2012
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Clockwise

Esteemed Pedelecer
Jun 28, 2013
438
53
Well it seems today was my lucky day so the bike I wanted was on offer after a mislisting and so bad reviews.

www.amazon.co.uk/exec/obidos/ASIN/B006KAZ7LG/ref=ox_ya_os_product

Unless my partner decides she wants the bike I'm going to look at adding a front hub motor and stashing all the battery's and junk needed in the top bar/mid bar gap like an old style motorbike fuel tank. Also means less messy wires coming back.

Any ideas on what kit/kits to get?

I keep coming across dozens of controllers and with/without hall sensors(?) and torque sensors and other sensors, what ones are good bad? Prefer less wires but if the extra sensors will save unseeded ware on the motor or battery's then surely it is good.

Also respoke or new wheel, I'm not a pro wheel builder but have done a couple.
 

RobF

Esteemed Pedelecer
Sep 22, 2012
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