Conversion kit build for Brompton

[Woosh]

To build a good wheel, you need to register the settings from the original Brompton wheel on your truing stand so that you reproduce them on your motor wheel.
Plastic truing stands don't work.
You'll need a truing stand made from steel to build wheels.
By the time you've paid for the truing stand (about £100+), £60 worth of air freight for the Q70 motor from bmsbattery.com (the only retail source of Q70 I know of), paypal's poor exchange rate (about $1.15 for your £), it's difficult to see where the saving would come from. That's even before looking into sourcing correct spokes, import duty and VAT.

Q70 36V250W Front Driving V-Brake Hub Motor RPM 328

Q70 36V 250W Front Driving V-brake, rim-brake E-Bike Hub Motor. Waterproof Hall Sensor and Sensorless compatible plug.

bmsbattery.com

 

[vfr400]

Hi

Would anyone know if this PAS would fit the brompton. Its the only one that splits apart so avoids removing the crank.

Dual Hall Sensor D12 Signals Easy Installation PAS Assemble Left

Dual Hall Sensor D12 Signals Easy Installation PAS

bmsbattery.com

Get a conventional one. The 10 magnets or fewer seem to be most compatible. 12 magnets often have compatibility issues. There are always problems when fitting pedal sensors whichever type you get. Removing a crank takes 30 seconds.

Thanks did you fit your assembly onto a brompton?

I used a Q85 on a Brompton

 

[vfr400]

To build a good wheel, you need to register the settings from the original Brompton wheel on your truing stand so that you reproduce them on your motor wheel.
Plastic truing stands don't work.
You'll need a truing stand made from steel to build wheels.
By the time you've paid for the truing stand (about £100+), £60 worth of air freight for the Q70 motor from bmsbattery.com (the only retail source of Q70 I know of), paypal's poor exchange rate (about $1.15 for your £), it's difficult to see where the saving would come from. That's even before looking into sourcing correct spokes, import duty and VAT.

Q70 36V250W Front Driving V-Brake Hub Motor RPM 328

Q70 36V 250W Front Driving V-brake, rim-brake E-Bike Hub Motor. Waterproof Hall Sensor and Sensorless compatible plug.

bmsbattery.com

I build my wheels while sitting in bed watching TV. I've never used a truing stand. For truing, I put the wheel in the forks and use a zip-tie as a pointer.

 

[RossG]

I build my wheels while sitting in bed watching TV. I've never used a truing stand. For truing, I put the wheel in the forks and use a zip-tie as a pointer.

There's a joke there somewhere but I just can't think of a suitable one ATM.

 

[Gavin]

I build my wheels while sitting in bed watching TV.

Do you not find the bike makes the sheets/ duvet a bit oily?!

 

[Nealh]

TBK sell AKM74sx in a 349mm rim for a Brommie.

 

[Woosh]

I build my wheels while sitting in bed watching TV. I've never used a truing stand. For truing, I put the wheel in the forks and use a zip-tie as a pointer.

If you have to produce a wheel every hour, you'll soon do things a certain way and can't watch anything but where the threaded end of the spokes and the top of the nipples go.
You can't use the spoke keys because they'll mark the nipples, you can't bent the spokes because they will scratch the paint on the rim when you pass them between other spokes.
Also, 36 spokes * 15 turns = a lot of screwdriver turns, you don't want to overdo, take back and redo.
Even after all that, bmsbat charge $155 a motor + £60 airfreight, SJS charge £35 for the rim. 36 spokes would cost extra £15. You are looking at about £250 for material!
I know I sell the lowest cost Brompton kit there is.

 

[vfr400]

There's a joke there somewhere but I just can't think of a suitable one ATM.

It made me think of this:

https://twitter.com/i/web/status/1008004069703610369

 

[Woosh]

TBK sell AKM74sx in a 349mm rim for a Brommie.

they still retail at $155 though.

1.6kg AKM-74SX 36V250W EBike Front Driving Hub Motor Fork Size 74mm for Brompton Bike [AKM-74SX 36V250W Front Motor] - $152.00 : Zen Cart!, The Art of E-commerce

Zen Cart! 1.6kg AKM-74SX 36V250W EBike Front Driving Hub Motor Fork Size 74mm for Brompton Bike [AKM-74SX 36V250W Front Motor] - ★★★★★ AKM-74SX 36V250W Front Driving Hub Motor V-brake, rim-brake Fork size 74MM Specification: 1. Voltage: 36V. 2. Brake type: V-brake, rim brake are compatible 3...

www.topbikekit.com

 

[omarshaffi]

To build a good wheel, you need to register the settings from the original Brompton wheel on your truing stand so that you reproduce them on your motor wheel.
Plastic truing stands don't work.
You'll need a truing stand made from steel to build wheels.
By the time you've paid for the truing stand (about £100+), £60 worth of air freight for the Q70 motor from bmsbattery.com (the only retail source of Q70 I know of), paypal's poor exchange rate (about $1.15 for your £), it's difficult to see where the saving would come from. That's even before looking into sourcing correct spokes, import duty and VAT.

Q70 36V250W Front Driving V-Brake Hub Motor RPM 328

Q70 36V 250W Front Driving V-brake, rim-brake E-Bike Hub Motor. Waterproof Hall Sensor and Sensorless compatible plug.

bmsbattery.com

Appreciate you would rather me buy the kit but I’ll still learn by doing myself and that’s priceless to me

 

[Nealh]

they still retail at $155 though.

1.6kg AKM-74SX 36V250W EBike Front Driving Hub Motor Fork Size 74mm for Brompton Bike [AKM-74SX 36V250W Front Motor] - $152.00 : Zen Cart!, The Art of E-commerce

Zen Cart! 1.6kg AKM-74SX 36V250W EBike Front Driving Hub Motor Fork Size 74mm for Brompton Bike [AKM-74SX 36V250W Front Motor] - ★★★★★ AKM-74SX 36V250W Front Driving Hub Motor V-brake, rim-brake Fork size 74MM Specification: 1. Voltage: 36V. 2. Brake type: V-brake, rim brake are compatible 3...

www.topbikekit.com

Plus the p&p and duty as well, just posted as another option.

 

[omarshaffi]

If you have to produce a wheel every hour, you'll soon do things a certain way and can't watch anything but where the threaded end of the spokes and the top of the nipples go.
You can't use the spoke keys because they'll mark the nipples, you can't bent the spokes because they will scratch the paint on the rim when you pass them between other spokes.
Also, 36 spokes * 15 turns = a lot of screwdriver turns, you don't want to overdo, take back and redo.
Even after all that, bmsbat charge $155 a motor + £60 airfreight, SJS charge £35 for the rim. 36 spokes would cost extra £15. You are looking at about £250 for material!
I know I sell the lowest cost Brompton kit there is.

I know I can buy it from you you’ve made that clear through a number of your posts but as I said I want to do something myself not as a commercial venture but for enjoyment.

 

[Woosh]

I want to do something myself not as a commercial venture but for enjoyment.

it's always useful to know how to true a wheel or replace a broken spoke but what you try to do is more than wheel truing, it's wheel building and that's a bit of a special trade.
Have you converted a bike before?

 

[omarshaffi]

it's always useful to know how to true a wheel or replace a broken spoke but what you try to do is more than wheel truing, it's wheel building and that's a bit of a special trade.
Have you converted a bike before?

No I’ve never converted a bike before. But like with anything I can learn. Maybe fail. But then learn some more.

 

[Woosh]

you are not going to fail if you follow the advice of members on here.
I often recommend customers who want to do special projects to join the forum and post their questions on here because the collective wisdom and knowledge is greater than any individual's.
However, converting a Brompton is not going to be cheap because of the fold. Cables have to be carefully planned, battery can only be placed in one or two places.
You will need electrical skills as much as mechanical skills because you will likely need to adjust the length of cables. I had to order a special controller for the last reason.

 

[omarshaffi]

you are not going to fail if you follow the advice of members on here.
I often recommend customers who want to do special projects to join the forum and post their questions on here because the collective wisdom and knowledge is greater than any individual's.
However, converting a Brompton is not going to be cheap because of the fold. Cables have to be carefully planned, battery can only be placed in one or two places.
You will need electrical skills as much as mechanical skills because you will likely need to adjust the length of cables. I had to order a special controller for the last reason.

Appreciate that and also respect that you’re giving honest advice and sharing your thoughts as well. I’ve gained skills and experience through my career and hobbies that will hopefully benefit me.

 

[Nealh]

I taught my self wheel building a few years ago and thoroughly enjoy building them, tbh I find it therapeutic and one can true a wheel up in 15/20 mins. On a bad day I just put it to bed then pick it up again the next day.

The day we stop learning is the day we might as well call it a day.

 

[omarshaffi]

I taught my self wheel building a few years ago and thoroughly enjoy building them, tbh I find it therapeutic and one can true a wheel up in 15/20 mins. On a bad day I just put it to bed then pick it up again the next day.

The day we stop learning is the day we might as well call it a day.

That’s true.

I work for a global accounting practice with some of my tax partners having over 35 years of tax advisory, technical knowledge, and have provided advice on complex tax matters usually cross border...every single day they learn, sometimes by research and sometimes by asking a junior graduate. So yes I second that point, regardless of who you are you can always learn.

 

[Woosh]

of course I tried to sell you my kit but the reason I seem to dig holes in your DIY project is not for my benefit.
Vfr400 and NealH have helped hundreds if not thousands of members sorting out their bikes over the years. However, your project is more difficult than most. It's importing your kit from China + making it work + making it look nice. Any one of these 3 is fraught with unkowns.
Too risky.

 

[omarshaffi]

of course I tried to sell you my kit but the reason I seem to dig holes in your DIY project is not for my benefit.
Vfr400 and NealH have helped hundreds if not thousands of members sorting out their bikes over the years. However, your project is more difficult than most. It's importing your kit from China + making it work + making it look nice. Any one of these 3 is fraught with unkowns.
Too risky.

Unknown’s is just part of life. Perceived risk is always different depending on an individual’s skill set and risk appetite.

You seem to dig holes and that’s it whereas others are actually offering constructive criticism and solutions. I appreciate you’re a trade member but most of your posts are just marketing which is also fine but it’s getting a bit repetitive.

As I said I’m looking forward to the build aspect of making a one-off not producing dozens of them.

Derek took time to build his but I’m sure it would have been much easier buying a kit, but he didn’t.