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QFour
05-10-2015, 21:28
Built one for SWMBO and have the parts for mine. Looked at lots of options including hub motors and mid drives from Bosch. On one forum a guy was moaning about the demise of his Bosch motor after 2 years and the prospect of spending 700 to get a new one. I looked at what we had and what we really needed. All you really need is a bit of help up the hills and a lot of help up the really steep buggers. So I did some research and found the Bafang 8Fun motor to be the most popular. Comes in various guises from the legal 250w to the not so legal 750w. Problem seems to be lack of gearing. It's ok having a motor but if it's still hard work to pedal you need something extra. All mid drive motors seem to have one chainwheel on the front and any number of gears on the back. Normally 8 seems to be something to do with a better chain. So limited to only 8 gears. I tried a Bosch one for 1/2 an hour thanks to Halfords up and down the hills round Nottingham. Not the easiest thing to pedal without the motor and still hard work on some of the steep hills so 8 gears was not enough.

More reasearch lead to an SRam Dual Drive. Similar to the old 3 Speed from Yester year but with room for an eight speed rear shifter so that gives 24 gears so back to what we had to start with on SWMBO's bike. These drives are readily available from the likes of Amazon just don't try to find one with a rim attached to it. Thats where the fun comes in. Make your own wheel. Quiet satisfying really. You have a hub a rim and a load of spokes. Lots of info on what to do and plenty of sites will help you work out spoke lengths.

The rest is quiet simple really. A light weight bike with a 68mm botton bracket. Throw the telescopic forks away and save 2kg by fitting some standart ones instead. Remove the cranks and bearing and fit motor. Fit a luggage rack and find a battery. Fit the wiring.

I have ordered my battery parts. Just got to make a box.

You can get parts from these guys Eclipsebikes (http://www.eclipsebikes.com/)

Cost 360 for the kit .. 300 for a battery and expect about 200 for the rear gears and rim.

What do you finish up with.

A Hybrid Electric Bike with a range of about 30 miles. A bike you can pedal without electric if needed. A bike you can lift onto a bike rack without a crane ( removable battery ). Not really worth nicking especially if its not a new doner bike. It's got 24 gears so should get up most hills with little effort.

Just got to get mine finished now and see what it's like.

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Obanboy666
06-10-2015, 15:37
Built one for SWMBO and have the parts for mine. Looked at lots of options including hub motors and mid drives from Bosch. On one forum a guy was moaning about the demise of his Bosch motor after 2 years and the prospect of spending 700 to get a new one. I looked at what we had and what we really needed. All you really need is a bit of help up the hills and a lot of help up the really steep buggers. So I did some research and found the Bafang 8Fun motor to be the most popular. Comes in various guises from the legal 250w to the not so legal 750w. Problem seems to be lack of gearing. It's ok having a motor but if it's still hard work to pedal you need something extra. All mid drive motors seem to have one chainwheel on the front and any number of gears on the back. Normally 8 seems to be something to do with a better chain. So limited to only 8 gears. I tried a Bosch one for 1/2 an hour thanks to Halfords up and down the hills round Nottingham. Not the easiest thing to pedal without the motor and still hard work on some of the steep hills so 8 gears was not enough.

More reasearch lead to an SRam Dual Drive. Similar to the old 3 Speed from Yester year but with room for an eight speed rear shifter so that gives 24 gears so back to what we had to start with on SWMBO's bike. These drives are readily available from the likes of Amazon just don't try to find one with a rim attached to it. Thats where the fun comes in. Make your own wheel. Quiet satisfying really. You have a hub a rim and a load of spokes. Lots of info on what to do and plenty of sites will help you work out spoke lengths.

The rest is quiet simple really. A light weight bike with a 68mm botton bracket. Throw the telescopic forks away and save 2kg by fitting some standart ones instead. Remove the cranks and bearing and fit motor. Fit a luggage rack and find a battery. Fit the wiring.

I have ordered my battery parts. Just got to make a box.

You can get parts from these guys Eclipsebikes (http://www.eclipsebikes.com/)

Cost 360 for the kit .. 300 for a battery and expect about 200 for the rear gears and rim.

What do you finish up with.

A Hybrid Electric Bike with a range of about 30 miles. A bike you can pedal without electric if needed. A bike you can lift onto a bike rack without a crane ( removable battery ). Not really worth nicking especially if its not a new doner bike. It's got 24 gears so should get up most hills with little effort.

Just got to get mine finished now and see what it's like.

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Interesting read and very informative.
Problem is I have my heart set on a kalkhoff, still undecided which model to go for especially since they have recently brought out models with the battery concealed in the frame.
50 cycles are the importer, take a look at their website and let me know what you think.

Sharon the Cat
06-10-2015, 17:26
Tissy's Mrs (Dawn) swears by her electric bike. He says she goes up hills past all the lycra boys looking like Mary Poppins.
I have a Dawes Mohave that is only a year old & have set my heart on a Copenhagen Wheel. Trouble is I'll probably have to sleep with the back wheel as it costs $600 US.

Obanboy666
06-10-2015, 18:09
Tissy's Mrs (Dawn) swears by her electric bike. He says she goes up hills past all the lycra boys looking like Mary Poppins.
I have a Dawes Mohave that is only a year old & have set my heart on a Copenhagen Wheel. Trouble is I'll probably have to sleep with the back wheel as it costs $600 US.

That's cheap, the Kalkhoff bikes I'm seriously considering start at approx 1,500 up to 3,500 !

Tbear
06-10-2015, 18:30
That's cheap, the Kalkhoff bikes I'm seriously considering start at approx 1,500 up to 3,500 !

I would be tempted to spend 500 on a road bike and spend the three grand on taxis when the hills are steep or its raining:) Don't even think about cycling on ice. :scared:

Richard

QFour
06-10-2015, 19:09
Interesting read and very informative.
Problem is I have my heart set on a kalkhoff, still undecided which model to go for especially since they have recently brought out models with the battery concealed in the frame.
50 cycles are the importer, take a look at their website and let me know what you think.

Nice looking bit of kit but very expensive. Probably because of where it's built. How heavy is it, you are going to have to lift it. Some of the ones we looked at were heavy without the battery. It's limited to 250w so whats it like on hills. Limited number of gears and only shown on the flat. Be interesting to see how one performs up some nice hills. I had my heart set on a Vivax Assist at 2950. Ticked all the boxes including a hidden motor, weight wise it was only 12kg. SWMBO's bike weighs in at 18.7kg without the battery. So about 23kg with the battery pack.

Batteries are something else. I am building a battery pack with 3.2v 12ah cells. These are Lifep04 cells which have an 80% value after some 2000 charge cycles. Far in excess of the lithium batteries and you can always replace a cell rather than the whole lot at an inflated price. If they are lithium cells you will be replacing them every 3 years. Might be worth getting a quote.

Nickability .. Insurance is going to be expensive and you are certainly going to have to lock it to something. It's also very tempting to a thief. Lot of value in a second hand one considering the price new. No questions asked .. Nod Nod know what I mean. Other question springs to mind is second hand value. I saw one of the Vivax Assist bikes on ebay. Earlier model with a noisy motor but the guy was having trouble getting bids. He had it on at 1000 to start with and had to re advertise it. Got a few bids but nothing serious.

So if you are going to keep it long term and not worry about resale value then why not.

But .. I think you could build something better and have some fun. Mine has got a 350w motor without any markings. Its a light weight mountain bike frames without the front suspension. Now has 24 gears so not going to wreck a motor struggling up hills. It will run at optimum speed about 70 rpm for the cranks. Got walk assist as well at 6kmh and upto 9 assistance levels. You also get to find out how a bike works. Got tools for most jobs. Pedal removal and bottom bearing. You are more than welcome to use them if it helps. Can also point you in right direction for bits and pieces and what I used. Hope to get mine on the road by the end of the month so you could always try it.

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trevskoda
06-10-2015, 19:39
Seen a few at our local auction ,they go for about 125 as no one wants them only a novelty im told,plus a good socking and getting ditched by mad drivers soon puts folk of.

Craig4568
06-10-2015, 20:57
ZoomAir 2 | Zoom | Zoom Electric Scooter | Your Urban Transport Solution (http://www.zoom.sg/product/zoomair2/)



Forget bikes this is the FUTURE bit pricey but tiny

iampatman
06-10-2015, 21:13
Tissy's Mrs (Dawn) swears by her electric bike. He says she goes up hills past all the lycra boys looking like Mary Poppins.
I have a Dawes Mohave that is only a year old & have set my heart on a Copenhagen Wheel. Trouble is I'll probably have to sleep with the back wheel as it costs $600 US.

Hi Sharon,

I bought the FlyKly wheel, a similar product to the Copenhagen, in fact the guy behind FlyKly worked for Copenhagen and then shafted them and got his product out first. I was very dissatisfied. When it worked it was ok but, for example, from a standing start uphill you couldn't get the speed up for the motor to kick in. I fitted mine to a single speed bike so the gearing was a nightmare. Ok, so I could go faster on the flat and it helped on hills when I had an approach but that was about all the benefit. It's a great idea in principle and their marketing is great but it's not so good in reality. I sent mine back and got a full refund, stuck the bike in the cellar and bought a Boardman 24 speed hybrid from halfords, it'll probably keep me fitter and I can go up hills too :)
Pat

Sharon the Cat
07-10-2015, 05:13
Hi Sharon,

I bought the FlyKly wheel, a similar product to the Copenhagen, in fact the guy behind FlyKly worked for Copenhagen and then shafted them and got his product out first. I was very dissatisfied. When it worked it was ok but, for example, from a standing start uphill you couldn't get the speed up for the motor to kick in. I fitted mine to a single speed bike so the gearing was a nightmare. Ok, so I could go faster on the flat and it helped on hills when I had an approach but that was about all the benefit. It's a great idea in principle and their marketing is great but it's not so good in reality. I sent mine back and got a full refund, stuck the bike in the cellar and bought a Boardman 24 speed hybrid from halfords, it'll probably keep me fitter and I can go up hills too :)
Pat

Thanks Pat I'll bear that in mind. I'd really like a trial of the Copenhagen wheel before I spend the dosh. I love my bike so this seemed like a good compromise.

topefisher
07-10-2015, 07:11
Very informative and interesting read Qfour.

Have a 26" wheel older Trek 8000 ( very lightweight )but mint which I don't use now 21 gears. This is my intended project.
Have a 29" Cube led pro which I use now in the main with no assist.

We rented some 8fun rear wheel driven mountain bike versions in France a couple of weeks ago.
They were brilliant and really impressed. Full or no pedal assist. After using a friends electric folder for a day or two a year ago the mountain bike rented was much better. Lighter and big gear range made a large difference for me.

Think I will be doing the rear wheel 250w conversion on the Trek which will retain the 21 gears as can still get the 7 speed sprocket on the hub/wheel. This is gonna be the cheapest option for me and will be around 375-460 for at least a 11ah decent battery in the kit.

Options are still open at the moment with research ongoing.

QFour
07-10-2015, 07:17
Thanks Pat I'll bear that in mind. I'd really like a trial of the Copenhagen wheel before I spend the dosh. I love my bike so this seemed like a good compromise.

You might as well fit a hub motor. Similar sort of device. Switch on and off as required. Not that great on hills and on a long one you can cook the motor as it is struggling trying to get upto speed. Ok on the flat.

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trevskoda
07-10-2015, 14:35
ZoomAir 2 | Zoom | Zoom Electric Scooter | Your Urban Transport Solution (http://www.zoom.sg/product/zoomair2/)



Forget bikes this is the FUTURE bit pricey but tiny

not any more ,this is stand on wheel auto giro $250 and selling like mad in usa.

caledonia
07-10-2015, 14:57
The KTM looks the part and goes very well but only 18 miles on full power is a bit poor considering the price.

QFour
07-10-2015, 16:09
Looks like Bosch have taken over the world of E-Bikes. Everyone uses the same motor. If it breaks then its agro and you cannot use it. It's impossible to turn it back to a normal bike. They also use Lithium Ion batteries which have a use by date of about 3 years. Then it's a new battery at their price. The new Lifep04 batteries are much better and last considerably longer. At least with my conversion I can always move it to another bike. Remove it and go back to pedals or just swap bits about. You need a dongle fitting to the Bosch type bikes at some 300 if you want to go faster the 15 mph and it mucks the speedo up as you have to double it :lol-053: All it does is fools the motor into thinking the bike speed is wrong. Go and try one without the power they are not that nice to ride :scared:

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Tbear
07-10-2015, 17:16
Looks like Bosch have taken over the world of E-Bikes. Everyone uses the same motor. If it breaks then its agro and you cannot use it. It's impossible to turn it back to a normal bike. They also use Lithium Ion batteries which have a use by date of about 3 years. Then it's a new battery at their price. The new Lifep04 batteries are much better and last considerably longer. At least with my conversion I can always move it to another bike. Remove it and go back to pedals or just swap bits about. You need a dongle fitting to the Bosch type bikes at some 300 if you want to go faster the 15 mph and it mucks the speedo up as you have to double it :lol-053: All it does is fools the motor into thinking the bike speed is wrong. Go and try one without the power they are not that nice to ride :scared:

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Which is why I went with a road bike instead of electric. If you want to do reasonable distance on an electric bike between charges which if you are not on hookup, could well be a couple of weeks apart, you are going to have to put some effort in. A reasonable road bike weighs very little and the thin high pressure tyres have very little rolling resistance so are easy to peddle. Add to that a sensible set of gears and you will be surprised how easy a 10 mile ride is unless you are in the Alps.

Electric bikes weigh in quite heavy before you add the battery. The tyres are wide and run at lower pressure so are much more difficult to peddle. I am sure they are wonderful to run to the shops when you are at home but I think I will stick to my road bike when away.

Richard

m30
07-10-2015, 17:25
I bought 2 Hiabike Sduro's before our recent trip away. I got the full suspension All Mountain and the wife got the Hard seven. Haibike do 2 ranges, the X Duro that uses the Bosch system, and the S Duro that uses the Yamaha system.
I went for the Yamaha system for the following reasons;
1 Twin front rings on mine with the option to fit on my wifes
2 smaller motor
3 higher torque
4 better range due to a better selection of gear ratios

We were away for a month, and i did 450 miles on mine, the wife 380, 90% of this was off road in the Black Forest and area around the Alpen Strasse in southern Germany. You can point the bike at any hill and know you will get up it, and running in std on very hilly ground you get 30 - 40 miles range, thats if your up to going that far. On the flat in eco you would probably get 50 miles if you so wished.

I was sceptical before we got them, but they are absolutely awesome. I think you will always get better range from a crank drive pedal assist system over the hub system due to the motor revs can be kept higher.

I do some of the trail centres in the North of England and Southern Scotland. My local one is Gisburn Forest. 1 lap of the Red Route which is 12.6 miles used to nearly put my lights out, taking 1 hour 45 mins plus breather stops around 2 1/2 hours in total, i can do one lap in 1 hour 10 mins on the Haibike without stopping, and 2 laps in Eco in 2 1/2 hours.

Stu

QFour
07-10-2015, 19:01
Good choice. At least you have a choice of gears. The Bosch is limited to 8 and looks like no way to change it as they have done everything inside the box. I also liked the Shimano one but it's only available on one of the Scott bikes. They have exclusive use of it so it's not going to go to do much with only one seller.

Glad you like yours .. Looking forward to getting mine finished.

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hextal
07-10-2015, 19:18
If I was going to get an electric KTM, it would be something like this....

http://www.ebay.co.uk/itm/Electric-KTM-RC8-EV-Electric-Vehicle-Mavizen-TTX02-AGNI-Motors-95R-Motorcycle-/111657430174?nma=true&si=dGL5pHWh%252FjNnVjlLo%252B8YFhwhaCI%253D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

hextal
07-10-2015, 20:01
Yeah. Love my RC8, but definitely fancy one of their thumpers to keep it company.

Agreed, the electric stuff looks cheap to run in a snapshot but really ain't good long term at all.


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