E-Conversion Kit for Bakfiets Troy Cargo Trike - Please help!

ManMaid

Finding my (electric) wheels
May 29, 2020
13
0
Hi Pedelecs

I am a handyman working in London and am in the process of swapping my old diesel builder's van for an electric cargo trike. Hoping to be ready for the expansion of the ULEZ next year and to make some substantial savings on transport costs .

So, I purchased a second-hand Bakfiets Troy cargo trike, under the impression that I would be able to convert it to electric by getting a hub-motor for the rear wheel. "Easy!", I thought..haha!

I have converted the box on the front to make it lockable and able to fit my toolboxes. I've been riding it for a few weeks now and it feels very comfortable when laden although sketchy on corners and pot holes due to the 3 wheels. However, I'm exhausted by the time I get to jobs and desperately need the assistance of a motor to get up the hills and deal with the stop-start at traffic lights or as pedestrians, eyes glued to phones, randomly step out in front of me. Grrr

I realised that I can't just replace the rear wheel with a hub motor wheel because I have a 7-speed hub gear with back pedal brake. I really need that back brake when I'm carrying 150Kg of tools and suicidal zombies keep jumping into the road. There are no weld bosses on the rear stays for mounting brake calipers. I could add a deralieur and freewheel cassette on the E-hub, which would not need to be expensive.

So, due to the brake problem, my local bike shop recommended that I try a mid-mount motor. This sounded perfect from my research until I ordered one and it would not fit.

Bakfiets make two versions of the Troy trike, one is mid mount electric and the other, like mine, is standard human powered. I realise today that the two frames are different, in order for there to be space for the mid mount motor.

I now have the following options:

1. Forget the e-conversion and just keep pedalling.
2. Find someone who can weld brake bosses to the seat stays and get a rear hub motor kit.
3. Fit two hub motors, one to each of the two front wheels. Synchronise them so I dont go round in circles?!?
4. Find a different supplier for mid mount motor.
5. Find a different solution.

PLEASE HELP
Any comments and feedback much appreciated.

THANK YOU
 

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Benjahmin

Esteemed Pedelecer
Nov 10, 2014
2,590
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Hats off to you for even considering option 1, however none of us are getting younger, and this ain't Amsterdam.
What mid motor did you try? It's going to depend on the bottom bracket configuration. A few more detailed photo's and Tony from Woosh may be able to help you.
I think getting a mod to accept a disc caliper would be favourite. The stopping power of a 203mm hydraulic disc would be most welcome (I assume there's brakes on the front somewhere). Then a rear wheel bpm motor with as many deraileur gears as you can fit.
Unfortunately the two motor option would be obviously illegal and as there was a police clamp down on rickshaw cabs in London this last year...........well lets just say they now know what they're looking for.
 
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Savlona

Finding my (electric) wheels
May 30, 2020
6
2
Funnily enough, I've been there with my own kid carrying saga. I'd agree with the previous poster that putting a rear hub motor on and upgrading the brakes is your best bet. A mid motor is fab on hills but unlikely to prove cost effective for you.
 
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FJC71

Pedelecer
Mar 1, 2020
47
16
Hi,
There seems to be an electric version of your bike.
That bike is only rated for a 100kg load in the front yours is rated for 80kg and 25kg on the rack. The frame may not be able to take the loads you are suggesting, I would be looking at reducing the weight you are proposing to carry or looking at a completely different solution before considering going further with a conversion on that bike. I suggest first check with the manufacturers to see if the frame can cope with your loads.

Looking at the specification of the electric version this is fitted with a mixture of drums of the font and discs on the rear. The motor is a 36v 250w rear hub, no mention of the torque though.

A new kit would be about £500 if sourced in the UK. Wheels, brakes and a new gearing system on top of that ,it wont be a cheap conversion. I have no idea about the feasibility of converting to drum brakes or discs at the back

if you can live with the weight limitation it might be cheaper and or easier to sell the bike and get an electric model.
 

ManMaid

Finding my (electric) wheels
May 29, 2020
13
0
Hats off to you for even considering option 1, however none of us are getting younger, and this ain't Amsterdam.
What mid motor did you try? It's going to depend on the bottom bracket configuration. A few more detailed photo's and Tony from Woosh may be able to help you.
I think getting a mod to accept a disc caliper would be favourite. The stopping power of a 203mm hydraulic disc would be most welcome (I assume there's brakes on the front somewhere). Then a rear wheel bpm motor with as many deraileur gears as you can fit.
Unfortunately the two motor option would be obviously illegal and as there was a police clamp down on rickshaw cabs in London this last year...........well lets just say they now know what they're looking for.
Thank you for your advice, Benjamin.
I was wondering about the legalities and whether they get enforced. I guess changing the labels on the motors isn’t a good option then?
There are standard v-brakes on the front wheels but I can’t get them to lock up and they feel under-rated. Would love to go hydraulic disk on a rear hub. How do I find someone that can weld disk brake mounts?
It was a Bafang 250W motor that wouldn’t fit around the bottom bracket. It was supplied by Tony at Woosh and I am in communication with him. He recommended that I come here!
 

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ManMaid

Finding my (electric) wheels
May 29, 2020
13
0
Hi,
There seems to be an electric version of your bike.
That bike is only rated for a 100kg load in the front yours is rated for 80kg and 25kg on the rack. The frame may not be able to take the loads you are suggesting, I would be looking at reducing the weight you are proposing to carry or looking at a completely different solution before considering going further with a conversion on that bike. I suggest first check with the manufacturers to see if the frame can cope with your loads.

Looking at the specification of the electric version this is fitted with a mixture of drums of the font and discs on the rear. The motor is a 36v 250w rear hub, no mention of the torque though.

A new kit would be about £500 if sourced in the UK. Wheels, brakes and a new gearing system on top of that ,it wont be a cheap conversion. I have no idea about the feasibility of converting to drum brakes or discs at the back

if you can live with the weight limitation it might be cheaper and or easier to sell the bike and get an electric model.
Hi
Mine is the Bakfiets.
I am being cautious with her especially when laden. In reality I would probably be maxing out at 80Kg up front anyway. However, I fully appreciate your comments regarding structural damage to the frame.
I’m in for about £1500 so far for bike, box mod and motor so am willing to pay a bit more for brake and gear upgrade.
Looking for someone who can weld bike frames. Any suggestions around West London?
 

Savlona

Finding my (electric) wheels
May 30, 2020
6
2
Hi,
There seems to be an electric version of your bike.
That bike is only rated for a 100kg load in the front yours is rated for 80kg and 25kg on the rack. The frame may not be able to take the loads you are suggesting, I would be looking at reducing the weight you are proposing to carry or looking at a completely different solution before considering going further with a conversion on that bike. I suggest first check with the manufacturers to see if the frame can cope with your loads.

Looking at the specification of the electric version this is fitted with a mixture of drums of the font and discs on the rear. The motor is a 36v 250w rear hub, no mention of the torque though.

A new kit would be about £500 if sourced in the UK. Wheels, brakes and a new gearing system on top of that ,it wont be a cheap conversion. I have no idea about the feasibility of converting to drum brakes or discs at the back

if you can live with the weight limitation it might be cheaper and or easier to sell the bike and get an electric model.
I had the non assist Big, then the mountain curve. Both were built like tanks, and I carried large kids and lots of shopping in the mountain- once I carried my boys, my friends twins and the friend had a backie on the rear rack.
 
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ManMaid

Finding my (electric) wheels
May 29, 2020
13
0
I had the non assist Big, then the mountain curve. Both were built like tanks, and I carried large kids and lots of shopping in the mountain- once I carried my boys, my friends twins and the friend had a backie on the rear rack.
That’s good to hear. :)
 

ManMaid

Finding my (electric) wheels
May 29, 2020
13
0
Funnily enough, I've been there with my own kid carrying saga. I'd agree with the previous poster that putting a rear hub motor on and upgrading the brakes is your best bet. A mid motor is fab on hills but unlikely to prove cost effective for you.
Thank you for pointing me in the right direction. :)
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
That rear Disc brake converter might just work, the drop out on it is 10.5mm so a geared hub axle with fit it.
 
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Benjahmin

Esteemed Pedelecer
Nov 10, 2014
2,590
1,747
70
West Wales
Good find on the brake adaptor, can't see any detail but it's worth a try at the price, see what size disc it will accomodate. That then clears the way for a rear hub.
Have you thought of Magura HS11's for the front. You would end up with two levers so not sure how that would work out. But they're far superior to standard V brakes. Do keep an eye on the rim wear though !
On the legality, it's two motors that are illegal. The high torque bpm motor that Tony supplies is labelled 350w so technically illegal, but there may be a work around for that. I'm only focusing on this aspect as your rig is bound to attract attention. It may be better for you to have a motor with a winding code that will give less rpm but more torque. So you wouldn't be getting anywhere fast but you'd get up the hills. This way the motor would be operating nearer it's no load speed so at maximum efficiency giving you the best miles/watthour of battery.
I like this project - wish I'd got a reason to do it myself. :cool:
 
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Nealh

Esteemed Pedelecer
Aug 7, 2014
20,917
8,533
61
West Sx RH
Any hub will need to be a low rpm/HT for the conversion, the OP has already mentioned the instability.
 
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peter.c

Esteemed Pedelecer
Apr 24, 2018
1,612
493
thurrock essex
Most of these brake adaptors are flimsy steel, they work better when the nuts and bolts are replaced have tried several from china, will work with 160mm discs
Used as a template and made in a thicker steel plate but this also depends on the drop outs horizontal or vertical
 
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ManMaid

Finding my (electric) wheels
May 29, 2020
13
0
Good find on the brake adaptor, can't see any detail but it's worth a try at the price, see what size disc it will accomodate. That then clears the way for a rear hub.
Have you thought of Magura HS11's for the front. You would end up with two levers so not sure how that would work out. But they're far superior to standard V brakes. Do keep an eye on the rim wear though !
On the legality, it's two motors that are illegal. The high torque bpm motor that Tony supplies is labelled 350w so technically illegal, but there may be a work around for that. I'm only focusing on this aspect as your rig is bound to attract attention. It may be better for you to have a motor with a winding code that will give less rpm but more torque. So you wouldn't be getting anywhere fast but you'd get up the hills. This way the motor would be operating nearer it's no load speed so at maximum efficiency giving you the best miles/watthour of battery.
I like this project - wish I'd got a reason to do it myself. :cool:
Really appreciate the info. Will look into the hydraulic brakes up front, although two levers only works if I have no rear brake or really big hands! Will see if they can be modified to operate in parallel from one lever. I’m concerned about only having front brakes and sending myself over the bars. Gonna give the bolt on disk calliper a go but try not to use it too often.
Tony has recommended the Shengyi DWG22C 250W 48V due to its high torque at low speeds. Although he’s not got stock until mid July.This has a max power rating of 750W although nominal 250W.
Having just read the gov.uk website I can see that it states that an EPAC (pedelec) must have a max power of 250W. I’m guessing that a routine police check is only gonna pick up on what the label says although if someone gets injured then perhaps I may be in trouble? Just bought myself an air horn to reduce that risk!
 

ManMaid

Finding my (electric) wheels
May 29, 2020
13
0
Most of these brake adaptors are flimsy steel, they work better when the nuts and bolts are replaced have tried several from china, will work with 160mm discs
Used as a template and made in a thicker steel plate but this also depends on the drop outs horizontal or vertical
Thanks Peter
I thought that may be the case Just from looking at them online. I’ll follow your advice and change fixings and use thicker steel.
 

ManMaid

Finding my (electric) wheels
May 29, 2020
13
0
Any hub will need to be a low rpm/HT for the conversion, the OP has already mentioned the instability.
Yes definitely. I’ve got to keep the top speed down for safety reasons but the torque will be such a relief when taking off from the lights or going up hills.