Hi - I need some help choosing a bike for my wife

[jules_wake]

I would be scared of shelling out that much for something direct from China. I've had some great deals in the past but also some real rubbish.

 

[JohnCade]

Checkout the new Keyde motor, which is bigger and stronger. It looks like they've had a go at sorting out the reliability issues with the old one. The complete kit with a 10Ah battery is about £700 including duty. I'm tempted:

http://www.keyde.com/en/Product/motor/Rear_motor/2015/0827/116.html

How much does the kit weigh it at though? Motor is 2.3 kg so battery is what?

 

[Deleted member 4366]

Have a look at their website, you lazy bar steward. It's all there. That's why I gave you the link.

 

[JohnCade]

Yes, I found an S200 kit which is more the thing. Seems to be about 2.8 kg total with a 6.8 ah battery. Seems to sell through eBay for around $800 + VAT and any duty.

Actually the kit seems to be only available from a Chinese language site or direct, and the above doesn’t include the LCD display.

I wonder if it would do me?

 

[Deleted member 4366]

I would be scared of shelling out that much for something direct from China. I've had some great deals in the past but also some real rubbish.

Keyde are an established company. Forum members have been trading with them for at least 4 years. I usually see them at the Shanghai Bike Show, but I don't think they were there this year. I don't think you have anything to worry about. Their website changes to English if you click the flag at the top.They have a Ebay shop too:

http://www.ebay.com/sch/2012yoyokeyde/m.html?item=252062060107&rt=nc&_trksid=p2047675.l2562

I would avoid the old smaller cassette motor unless you're very light.

 

[jules_wake]

So could I just go and buy a reasonable road bike then fit one of these with competent diy skills. The thing I like about the cytronex option is that you are keeping weight low in case of no battery. What advantages does this option give in terms of usage?

 

[JohnCade]

Seems to be about the same weight as the Cytronex with more power and range. A 4ah battery won’t get you far if you use it much on hilly roads. So half as much again capacity would be useful. Also this one has an LCD which will allow you to control the power you want to use while the other is just on/off; and it can be fitted to a bike you own while the Cytronex is not sold as a kit.

They charge a lot for a fairly simple conversion like this would be too.

 

[Deleted member 4366]

So could I just go and buy a reasonable road bike then fit one of these with competent diy skills. The thing I like about the cytronex option is that you are keeping weight low in case of no battery. What advantages does this option give in terms of usage?

The Cytronex is a city bike, not for mountains. Trust me!

 

[jules_wake]

Seems to be about the same weight as the Cytronex with more power and range. A 4ah battery won’t get you far if you use it much on hilly roads. So half as much again capacity would be useful. Also this one has an LCD which will allow you to control the power you want to use while the other is just on/off; and it can be fitted to a bike you own while the Cytronex is not sold as a kit.

They charge a lot for a fairly simple conversion like this would be too.

Are you looking at front or rear hub?

 

[jules_wake]

The Cytronex is a city bike, not for mountains. Trust me!

So after a fair bit of reading I am pretty much set on a diy approach with a hub motor on a lightweight donor bike. I am thinking either a 700 road bike with straight handlebars or a fixed tail 26 inch mountain bike with front suspension. If I go with a kit what are some of the issues that determine the donor bike. Is it better to get the kit then the bike. I've got a spare Mountain bike for a test setup although it is a hydraulic brake which I understand might be a pain for electric brake cut off??
Finally I can't find a good side by side comparison of the various kits is there somewhere I could look....

 

[Deleted member 4366]

There's not really anywhere where you can see comparisons. There's a lot of choice of kits and components and they're changing all the time. If you want light weight, you choice is easier because there's not so many. I can't think of anybody in the UK that offers a light weight one. I've seen the Keyde kit sold in Europe, rebranded under the seller's own name.

It's important that you get a motor with the right speed, so don't buy any kit unless you know the motor rpm. 201 rpm is 25 km/h and 260 rpm about 32 km/h. You don't want to go much higher than that because it will have less effeciency at low speed, so less torque.

The cheapest low weight motor is the Q100 from BMSbattery.com, which weighs 2.2 kg. The Q100H is strong and durable. The lightest is the Keyde one with integrated controller, though there have been some reliability issues. The Keyde packs a fair punch for its size. I see that they have just released a new slightly bigger one.

 

[jules_wake]

Thanks for all your help I managed to find a shop in Nice which seems to specialise in the Q100 and they have a test setup so that is perfect. Will report back when I've had a look.

 

[Deleted member 4366]

Please let us know what happens, what products they have and what they say about them.

 

[anotherkiwi]

The lightest is the Keyde one with integrated controller, though there have been some reliability issues. The Keyde packs a fair punch for its size. I see that they have just released a new slightly bigger one.

3.3 Kg _with_ the 10 Ah batterie! I am in love

And the tiny battery fits in my tight frame in a standard bottle cage!

Quite expensive with a second range extender battery but weight saving has always come at a price. Thanks for the heads up d8veh!

 

[Deleted member 4366]

From memory, the girl at Keyde is called Sky. She was quite good at sorting you out. Jerrysimon might be able to provide her email address.

 

[jules_wake]

So in the end I tested a couple of bikes with hub drive and mid drive. I ended up with a mid drive 350w bafang. I was convinced by the mid drive on the basis it is more powerful and sort of felt more natural with the way it worked. Also was convinced by a sales guy that the mid drive would be better for hills.

I've now bought a decathlon hybrid bike which was 250 euros and has a rear rack. I'm waiting on the kit from em3ev in china who seemed the cheapest/best reviewed. Unfortunately the local suppliers of the bafang were going to be 200+ euros more expensive than from china and I was determined to try and get the bike motor and battery for under 1000 euros which will be tight....

I've not bought a battery yet as it looks like I near a rack mounted one to fit the bike. I've just seen a real deal on alibaba which is tempting. Any ideas whether this would be good??

http://www.aliexpress.com/store/product/36V-15AH-Rear-rack-Lithium-Battery-with-BMS-Charger-36V-500W-Electric-Bicycle-POWER-Akku-Li/1714144_32294136761.html

 

[anotherkiwi]

Is that frame steel or aluminum? My girlfriend has the same style frame and my thought was to put a mid drive on it and put a bottle battery under the frame, there is room between the frame and the mudguard.

 

[jules_wake]

It's aluminum I thought the same but all the cables run there and it is slightly curved. In the end I've found a cheapest battery from China which can go on the rear rack

 

[anotherkiwi]

I was thinking about standoffs to solve the cable issue.

 

[martinb]

I did not know you could change your wife for an ebike.

Do cycle shops do wife part exchange.....if so let me know..... Have old wife here at home, a little rough around the edges though nothing a little surgery would not sort out and love to exchange for a full suspension Haibike