Kettwiesel Trike Conversion

Ghnarumen

Finding my (electric) wheels
May 3, 2015
6
0
WestOfScotland
My wife and I took up recreational cycling, recently (fresh air and exercise), but she has suffered a frozen shoulder which has made upright cycling impossible for the moment. I bought a Kettwiesel delta trike for her to use and this has worked quite well but I would like to motorize it because there are hills where we live.

I don't want to interfere with the existing gears - rear 9 speed derailleur and Schlumpf Mountain drive - which seem to work well and provide a good range. A geared front hub (on the front, steered wheel) wouldn't interfere with the gears, shouldn't be too heavy, would be reasonably quiet, and shouldn't drag perceptibly if used without power (I hope).

Initially, I was interested in the Xiongda 2 speed motor (Panda Ebikes sell these in kits) because the gearing gives two speeds at which the motor can work efficiently but I've seen complaints that the motor can lock up and break if the wheel is pushed backwards. The nature of trikes is that they get pushed/pulled backward frequently so I suppose that this motor won't do. Although I saw mention that Xiongda might be taking steps to fix the problem, I haven't seen any postings that confirm that they have done so. Is anyone able to comment?

My attention is now taken by the Bafang QSWXK5 and the Mxus XF07. These motors seem comparable. One seller seems to be saying that the Bafang model has been superceded by QSWXK2 but I haven't been able to find out any more about it. Does anybody know more about this? I guess I would prefer a motor that has Hall sensors since they have a reputation for operating more smoothly than those without (with an appropriate controller).

I would like to use a bottle battery as there is provision behind the seat for 2 bottle holders. This would make the installation quite inconspicuous (which is one of my goals). A black anodized bottle case would be even more discreet. The controller could be mounted on the frame beneath the seat close by the battery. One of my concerns, though, is that this style (capacity) of battery may not be able to supply enough current to power the machine up hills. I've seen a comment about that somewhere but I don't know if it would apply in this context.

I would require a motor cable of about 1.6 - 1.7 metres to go between the motor and the controller. Presumably this is not so long as to cause a significant loss of energy to the motor. The rest of the gear would seem to be about as close together as on a conventional bike.

I have seen a kit offered by Cyclotricity and I am tempted to get this. It seems to use an XF07 (although Cyclotricity doesn't explicitly state this). The kit doesn't include torque arms but I would want to fit these to both sides of the (substantial but alloy) forks. The XF07 seems to have a short captive power lead leaving the motor via the axle. Is it possible to push the attached connector through the bolt hole on a torque arm? Does anybody here have experience of this? I don't fancy disassembling a new motor to break and re-make these electrical connections. Incidentally, the forks are spaced at ~101mm and the dropouts are ~10mm. The inner face of the dropouts is flush with the inner face of the forks above.

The Kett has 20 inch wheels using 32mm wide rims (basically, BMX rims). I can't see any supplier who offers a kit with wheels like this so I think I would, at a later date, take the motor out of the supplied wheel and relace it in a rim more like those already on the machine (if I can find one); the kit wheel would do to start with.

Hub manufacturers supply the motors with different windings to suit differing sized wheels. Again, suppliers don't seem very forthcoming about this information in their adverts; I guess they think this would be confusing for buyers. I have a persistent mistrust that they might supply the motors that they have in stock rather than ones which have the correct specification so what should I be looking for with either of these motors?

Kits generally supply replacement brake levers but I would prefer to keep the existing Avid BB7 components and operate some sort of microswitch to cut power to the motor. Also, Ive seen pedal sensors that split in two that look preferable to the sensor supplied by Cyclotricity. Are all these sensors interchangeable (they seem to have different numbers of magnets)?

Perhaps I want to change the kit to such an extent that I would be better off just buying the components but I fear that, if I attempted to do that, I would get nowhere with the project but just stall from inertia.

All helpful suggestions considered! (Actually, this will be invaluable help with my research for my forthcoming novel about ebiking in Russia.)

John
 
Last edited:

RobF

Esteemed Pedelecer
Sep 22, 2012
4,732
2,312
My wife and I took up recreational cycling, recently (fresh air and exercise), but she has suffered a frozen shoulder which has made upright cycling impossible for the moment. I bought a Kettwiesel delta trike for her to use and this has worked quite well but I would like to motorize it because there are hills where we live.

I don't want to interfere with the existing gears - rear 9 speed derailleur and Schlumpf Mountain drive - which seem to work well and provide a good range. A geared front hub (on the front, steered wheel) wouldn't interfere with the gears, shouldn't be too heavy, would be reasonably quiet, and shouldn't drag perceptibly if used without power (I hope).

Initially, I was interested in the Xiongda 2 speed motor (Panda Ebikes sell these in kits) because the gearing gives two speeds at which the motor can work efficiently but I've seen complaints that the motor can lock up and break if the wheel is pushed backwards. The nature of trikes is that they get pushed/pulled backward frequently so I suppose that this motor won't do. Although I saw mention that Xiongda might be taking steps to fix the problem, I haven't seen any postings that confirm that they have done so. Is anyone able to comment?

My attention is now taken by the Bafang GWSXK5 and the Mxus XF07. These motors seem comparable. One seller seems to be saying that the Bafang model has been superceded by GSWXK2 but I haven't been able to find out any more about it. Does anybody know more about this? I guess I would prefer a motor that has Hall sensors since they have a reputation for operating more smoothly than those without (with an appropriate controller).

I would like to use a bottle battery as there is provision behind the seat for 2 bottle holders. This would make the installation quite inconspicuous (which is one of my goals). A black anodized bottle case would be even more discreet. The controller could be mounted on the frame beneath the seat close by the battery. One of my concerns, though, is that this style (capacity) of battery may not be able to supply enough current to power the machine up hills. I've seen a comment about that somewhere but I don't know if it would apply in this context.

I would require a motor cable of about 1.6 - 1.7 metres to go between the motor and the controller. Presumably this is not so long as to cause a significant loss of energy to the motor. The rest of the gear would seem to be about as close together as on a conventional bike.

I have seen a kit offered by Cyclotricity and I am tempted to get this. It seems to use an XF07 (although Cyclotricity doesn't explicitly state this). The kit doesn't include torque arms but I would want to fit these to both sides of the (substantial but alloy) forks. The XF07 seems to have a short captive power lead leaving the motor via the axle. Is it possible to push the attached connector through the bolt hole on a torque arm? Does anybody here have experience of this? I don't fancy disassembling a new motor to break and re-make these electrical connections. Incidentally, the forks are spaced at ~101mm and the dropouts are ~10mm. The inner face of the dropouts is flush with the inner face of the forks above.

The Kett has 20 inch wheels using 32mm wide rims (basically, BMX rims). I can't see any supplier who offers a kit with wheels like this so I think I would, at a later date, take the motor out of the supplied wheel and relace it in a rim more like those already on the machine (if I can find one); the kit wheel would do to start with.

Hub manufacturers supply the motors with different windings to suit differing sized wheels. Again, suppliers don't seem very forthcoming about this information in their adverts; I guess they think this would be confusing for buyers. I have a persistent mistrust that they might supply the motors that they have in stock rather than ones which have the correct specification so what should I be looking for with either of these motors?

Kits generally supply replacement brake levers but I would prefer to keep the existing Avid BB7 components and operate some sort of microswitch to cut power to the motor. Also, Ive seen pedal sensors that split in two that look preferable to the sensor supplied by Cyclotricity. Are all these sensors interchangeable (they seem to have different numbers of magnets)?

Perhaps I want to change the kit to such an extent that I would be better off just buying the components but I fear that, if I attempted to do that, I would get nowhere with the project but just stall from inertia.

All helpful suggestions considered! (Actually, this will be invaluable help with my research for my forthcoming novel about ebiking in Russia.)

John
Blimey John, if your post is anything to go by that novel of yours will be longer than War and Peace.

To be serious, it should be possible to electrify your trike - there are a few on here who have done it.

Inevitably, there will be some minor engineering to be done along the way, so you won't be able to foresee all the snags before buying the kit.

I wouldn't worry too much about windings, other than to buy something specced for a smaller wheel, or a motor built into a correct sized wheel.

Nice trike, by the way.
 

eHomer

Esteemed Pedelecer
Aug 20, 2012
635
164
My avatar shows my Hase Lepus which I converted to electric a while ago.

It's almost identical to your Kettwiesel.

My conversion was much simpler, because I wanted to be able to quickly remove the motorised front wheel for when I want to use it unassisted.

They're so light that I just used a cheapo Q100 motor from BMS, together with an SO6S sine wave controller and lcd. The brakes are standard Hase (Magura) hydraulic discs rear and blocks front, so I fitted a hydraulic brake switch in the rear brake line.

It's important to get the 328rpm version, because of the small 20" front wheel.

For battery packs, I use the same 36 volt 10 amp lithium iron unit that fits my other eBikes. (I have two of them for extra range when necessary).

A really big advantage of the Hase trikes is the large rear carrier net between the rear wheels and very low down for low centre of gravity. I just put one or both batteries inside a bag on there, so they're very stealth.

I get about 25 miles range per battery, with assistance. I use it in the flatlands of Norfolk, but I'm a heavy bloke at 95kg, so maybe that balances it out.

With the "mountain" gear range and the lightness the Hase is very easy to pedal anyway, but the little 350w Q100 motor gives it a nice assisted acceleration, and takes the sting out of the occasional "hill" where i live.
 

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Ghnarumen

Finding my (electric) wheels
May 3, 2015
6
0
WestOfScotland
Blimey John, if your post is anything to go by that novel of yours will be longer than War and Peace.

To be serious, it should be possible to electrify your trike - there are a few on here who have done it.
RobF thanks for your encouragement. I'm really just hoping for some extra information before I take the plunge. It's good practice for my Russian novel, too!
 

Ghnarumen

Finding my (electric) wheels
May 3, 2015
6
0
WestOfScotland
My avatar shows my Hase Lepus which I converted to electric a while ago.

It's almost identical to your Kettwiesel...
eHomer thanks for those interesting photos. I hadn't appreciated quite how similar to the Kett the Lepus was. I understand that Hase are now using the Kett frame for Lepus models.

I see that you used a torque arm on the LH fork; did you use one on the RH side, too? You didn't have any problem getting the torque arm over the connector?

I want to stay with a nominally legal 250W motor but BMS do the SWXK5 motor. How easy did you find placing an order? Did you buy your motor laced into a wheel?
 

RobF

Esteemed Pedelecer
Sep 22, 2012
4,732
2,312
eHomer thanks for those interesting photos. I hadn't appreciated quite how similar to the Kett the Lepus was. I understand that Hase are now using the Kett frame for Lepus models.

I see that you used a torque arm on the LH fork; did you use one on the RH side, too? You didn't have any problem getting the torque arm over the connector?

I want to stay with a nominally legal 250W motor but BMS do the SWXK5 motor. How easy did you find placing an order? Did you buy your motor laced into a wheel?
A single torque arm is fine.

The motors you are considering are nicely pokey, but are not that powerful.

There is always risk of a motor spinning out, but one torque arm is more than enough to cover it.
 

anotherkiwi

Esteemed Pedelecer
Jan 26, 2015
7,845
5,786
The European Union
You haven't thought of trading up to a Klimax?

You can find bottle batteries on Alibaba which are up to 18 A with the new LG cells. They are longer than the smaller capacities but they are black!

Buy a motor and have it laced into the existing rim would be my suggestion.
 

eHomer

Esteemed Pedelecer
Aug 20, 2012
635
164
eHomer thanks for those interesting photos. I hadn't appreciated quite how similar to the Kett the Lepus was. I understand that Hase are now using the Kett frame for Lepus models.

I see that you used a torque arm on the LH fork; did you use one on the RH side, too? You didn't have any problem getting the torque arm over the connector?

I want to stay with a nominally legal 250W motor but BMS do the SWXK5 motor. How easy did you find placing an order? Did you buy your motor laced into a wheel?
I wasn't completely happy with that ready-made torque arm, I don't really like the ones fastened by a jubilee clip, so it was just a temporary one to test the motor. I've since made a bespoke one out of 6mm stainless steel plate, that fits exactly over the mudguard fixing lug. I'll take a photo of it tomorrow and post it on this thread.

Yes, the motor's short flying lead connector does pass through it. I had a puncture on one of my first ebikes and realised the need to be able to quickly remove a motor wheel at the roadside, so I've always made sure since that they can be simply unplugged.

I've always had really good service from BMS, the orders arrive within a fortnight, and everything has worked ok. I inevitably end up paying the Fedex customs and VAT charge though, invoiced a few weeks afterwards.

I've actually had two 328rpm Q100 motors from them, one laced into a 20" rim and one not ready laced, but complete with the bare rim and correct length spokes. The shipping fee was much cheaper unlaced, and was very simple to do, (thanks to Dave on this forum for encouraging me !)
 

Benjahmin

Esteemed Pedelecer
Nov 10, 2014
2,590
1,746
70
West Wales
I have used the Ezee torque bracket on my conversion. It comes with three pieces, one for the axle and two, of different lengths, to reach the mudguard lug. I put it on with the mudguard stay and a longer bolt. It's been fine and that's with the much bigger ezee motor.
 

eHomer

Esteemed Pedelecer
Aug 20, 2012
635
164
On the flat, I can get about 18mph unassisted, and a little more with assistance.

I generally "cruise" at 15 mph, which is very unstressed on it, unlike the lower revving motors in 20" wheels.

The Q100 is an amazing little motor, very quiet and light, and hardly any bigger than an old dynohub.
 
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Christopher Broers

Just Joined
May 13, 2017
4
1
United Kingdom
Hi gents, I'm about to do the same thing to a 2003 Kettwiesel.

We tried out the new 5000 pound Kettwiesel Steps with full suspension which was the Mercedes of a bicycle, but it is heavy and difficult to transport so decided to employ my engineering skills instead.

I have narrowed it to two options - the same conversion as eHomer (which looks a fantastic job!)
Or
A Bafang 8fun conversion

The rider is partially paralysed so everything is on one steering arm, it is therefore important to limit number of controller/screens. The Bafang conversion is going to be trickier, with a modification to the steering mechanism required, but the advantage is that it may help the rider's cadence and there appears to be less wiring

eHomer, do you find that driving the front wheel is advantageous off road? The Kettwiesel already has two wheel drive through the differential, perhaps the weight of the motor stops the front wheel from skidding.