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?

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.

My latest build

 

Endless-sphere.com • View topic - 24s HT3525 Kraken Build

 

My first build, which is probably more suited to you I would imagine. Geared drives with a lower voltage gives you some really good benefits.

 

http://www.pedelecs.co.uk/forum/classifieds/13763-giant-xtc-se-36v-500w-bafang-code-12-44-v.html

I was thinking more along the lines of something like these put together.

 

26B29BL | Ecosmo 26" New Beach Cruiser / Lowridge Bike | 7 SP SHIMANO,Rear Rack,Comfort Seat,Mudguards

EK26F36R | 8Fun 26" Electric Bike Conversion Kit | 36V 250W Motor, 36V Li-ion Battery with Panasonic cells

 

Would likely change the bike but you know something a little different.

read this thread:

http://www.pedelecs.co.uk/forum/electric-bicycles/13943-convert-buy-new.html

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.

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.

I'm now considering an Electra Cruiser 1 and a pannier + front wheel hub type kit from 8fun.

 

Bikes 2U Direct -- Leisure bikes : Cruisers -- Electra Cruiser 1 gents black bike

 

The only thing I am now thinking is how the hell do I make an e-coaster brake.

Get a direct drive motor and use regen.

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?

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?

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 :o

 

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.

Edited July 8, 201312 yr by jackhandy

1. Dedicated rear rack, something like this: Rack For Our 03 and 05 Battery Case - BMSBATTERY

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.

.....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 :o......

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 ;-)

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.

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

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.

My latest build

 

Endless-sphere.com • View topic - 24s HT3525 Kraken Build

 

My first build, which is probably more suited to you I would imagine. Geared drives with a lower voltage gives you some really good benefits.

 

http://www.pedelecs.co.uk/forum/classifieds/13763-giant-xtc-se-36v-500w-bafang-code-12-44-v.html

 

For me personally I think that is a reasonable good setup for that price under £1,100. Hands up to those who can do their own build.

 

MS

Well it seems today was my lucky day so the bike I wanted was on offer after a mislisting and so bad reviews.

 

http://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.

Well it seems today was my lucky day so the bike I wanted was on offer after a mislisting and so bad reviews.

 

Electra Cruiser Custom 1 Men's Urban Bike - Blue/Dark Blue, 26 Inch: Amazon.co.uk: Sports & Outdoors

 

Looks like the bike is single speed.

 

You don't need dozens on an electric bike, but a few, say three, would be good.

Well it seems today was my lucky day so the bike I wanted was on offer after a mislisting and so bad reviews.

 

http://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.

You're not far off with your calculation. You should think about a controller with a panel that gives several levels of pedal assist, and the other thing you should look at is hidden wire brake sensors instead of the ebrakes that they give with most kits. Also a torque arm is also useful in case your drop-outs aren't strong enough. Most motor kits offer a range of wheel sizes, so no point in building your own wheel unless you want it to match. The bike in your link has 36 spoke wheels, the same as the motor. Be careful with other bikes: 28 and 32 spoke wheels are fairly common.

Looks like the bike is single speed.

 

You don't need dozens on an electric bike, but a few, say three, would be good.

Yes, single speed with a rear hub coaster/brake so backpedel and the brake kicks in. I did a ride on the weekend of 30 miles on my regular mountain bike going across london and back via another route keeping in 2/3(front) and 5/7(rear) so mid geared and it was fine so if I swap the rear cog from a 22 to a 15-16 it should be perfect. If I needed to hill climb then I wouldn't be picking this bike ever lol

You're not far off with your calculation. You should think about a controller with a panel that gives several levels of pedal assist, and the other thing you should look at is hidden wire brake sensors instead of the ebrakes that they give with most kits. Also a torque arm is also useful in case your drop-outs aren't strong enough. Most motor kits offer a range of wheel sizes, so no point in building your own wheel unless you want it to match. The bike in your link has 36 spoke wheels, the same as the motor. Be careful with other bikes: 28 and 32 spoke wheels are fairly common.

As it has a coaster/hub brake on the back wheel do any sort of sensors for that exist?

 

My current to add list is this.

 

torque arms

http://www.bmsbattery.com/36v/450-a-pair-of-ebike-torque-arm.html

front hub motor/wheel - 250w 36v?

http://www.bmsbattery.com/ebike-kits/420-250w350w-q-85100sx-motor-e-bike-kit.html

controller(unsure what type assume the above is ok?)

display, mid mounted due to handlebar curves(above in kit again?)

right side(front) brake grip(again from above?)

thumb throttle, what does the button add?

http://www.bmsbattery.com/accessory/231-thumb-level-throttle.html

http://www.bmsbattery.com/ebike-parts/54-thumb-level-throttle-with-battery-meter-and-a-switch.html

battery, 10AH 36v?

Little confused here, are the black shrink wrapped box looking things the same as the nice aluminum cased ones? Should I be ignoring them all and buying the cell things and a pcb? I had it all kinda figured out when I was looking at buying a kit that came with a pannier thing but now it's all kinda gone up in the air

http://www.bmsbattery.com/36v/522-bottle-ebike-battery.html

http://www.bmsbattery.com/36v/495-36v-10ah-lithium-ion-electric-bicycle-battery-pack.html

Edited July 9, 201312 yr by Clockwise

Ok, some more searches and looking up just building a battery and not an ebike battery I found plenty about wiring up smaller AA looking battery cells into bigger packs. A little more info on the pcbs that balance them when charging and I should be good to go.

 

Headway 38120S LiFePO4 Battery Cell - 10x these?

+

Headway 38120 38140 Holder - however many to mount them 20 or so to have spares

+

Headway 38120 38140 Connector 20 or so again, plenty of spares

+

pcb?

Smart BMS 5~13 Cells in Series - BMSBATTERY

Now you're getting to the most difficult bit - deciding what to buy.

You should buy the kit with the LED panel:

Q100 36V250W-350W Front E-Bike Kit with LED Meter - BMSBATTERY

Remember that this motor runs out of steam at 15mph, unless you increase the voltage.

You have to have a vision of how and where you want to fit the battery before you decide which one to buy, The 38120 cells are relatively heavy for the size of battery. The aluminium cased ones normally fit on a rack.

 

I don't think you can fit sensors to coaster brakes, but it should be ok as long as you have one on the front, although that bike doesn't appear to have a front brake, which would be a big problem. The PAS sensor causes the motor to run on a bit, so you need at least one brake switch. The half-throttles are easiest to fit because they fit any bike that doesn't have twistgrip gears.

Now you're getting to the most difficult bit - deciding what to buy.

You should buy the kit with the LED panel:

Q100 36V250W-350W Front E-Bike Kit with LED Meter - BMSBATTERY

Remember that this motor runs out of steam at 15mph, unless you increase the voltage.

You have to have a vision of how and where you want to fit the battery before you decide which one to buy, The 38120 cells are relatively heavy for the size of battery. The aluminium cased ones normally fit on a rack.

 

I don't think you can fit sensors to coaster brakes, but it should be ok as long as you have one on the front, although that bike doesn't appear to have a front brake, which would be a big problem. The PAS sensor causes the motor to run on a bit, so you need at least one brake switch. The half-throttles are easiest to fit because they fit any bike that doesn't have twistgrip gears.

According to the description it should have a front brake. The multiple 1* reviews as it is badly listed on amazon is what I guess pushed the price down.

 

Hopefully this plan makes sense. The red bit will be some sort of plastic, thin metal or maybe even fibreglass "fuel tank" that I can put the controller and battery in. The yellow wires go upto the brake and the led/lcd thing and the throttle. Purple wire to the motor and the green bit is the motor. Orange to any sensor I need there?

 

http://i160.photobucket.com/albums/t171/pimptasticmofo/bikeplan_zpsca18b696.jpg

 

PS - Before someone says... I will be sticking with a blue and black theme so no crazy colour motors and cables.