Regular brompton to Electric brompton using brompton parts?

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yoho oy

Active Member
I was looking at some third party kits to convert regular brompton to electric. Price wise they are not great. When added to new bike cost, most of them go over new electric brompton price. There is really no financial initiative to modify new out of factory regular brompton. On other hand I had a theoretical idea - can regular brompton be converted to electric using brompton parts? Sure, it will not be cheap, but this is theoretical exercise.
What I am looking to are part list necessary to do that:

Brompton Electric travel charger set £80

Brompton Electric small bag - with frame £60
Brompton Electric - Front Fork Hook Assembly £10
Brompton Electric - P Clip For Motor Cable £1
Brompton Electric - 8.55Ah Battery £500
Brompton Electric - Torque Sensing Bottom Bracket £85
Brompton Electric - Front Carrier Block £135
Brompton Electric Mudguard Stays £6
Brompton Electric Front Wheel £600

£1477 in total? Comes close to some third party conversions...
Anything missing?
 

roley poley

Über Member
Location
leeds
If you are looking to ease those hills, bolting a 2nd smaller chain wheel on (as I and many others on this site do) will help pocket,knees and weight gain :okay:
 
OP
OP
Y

yoho oy

Active Member
No, I am not going to convert my bike or thinking about electric brompton. I went with regular brompton because of the weight and small dimensions when folded up. Battery, motor adds up weight and (maintenance) expense. This is just theoretical exercise. The question is more like "can it be done?" and "would it be less expensive than some 3'd party conversions?". For example ARCC charges £1,799.00.
 
I was looking at some third party kits to convert regular brompton to electric. Price wise they are not great. When added to new bike cost, most of them go over new electric brompton price. There is really no financial initiative to modify new out of factory regular brompton. On other hand I had a theoretical idea - can regular brompton be converted to electric using brompton parts? Sure, it will not be cheap, but this is theoretical exercise.
What I am looking to are part list necessary to do that:

Brompton Electric travel charger set £80

Brompton Electric small bag - with frame £60
Brompton Electric - Front Fork Hook Assembly £10
Brompton Electric - P Clip For Motor Cable £1
Brompton Electric - 8.55Ah Battery £500
Brompton Electric - Torque Sensing Bottom Bracket £85
Brompton Electric - Front Carrier Block £135
Brompton Electric Mudguard Stays £6
Brompton Electric Front Wheel £600

£1477 in total? Comes close to some third party conversions...
Anything missing?
Isn't Swytch about £500 ?
 
£624 for the Swytch Brompton kit.

The 2 speed electric Brompton is £2875.

Buy a normal 3 speed - £1315.
Swytch - £624.

Grand Total - £1939 - saving you £936.

You're welcome.
 

mitchibob

Über Member
Location
Treorchy, Wales
£624 for the Swytch Brompton kit.

The 2 speed electric Brompton is £2875.

Buy a normal 3 speed - £1315.
Swytch - £624.

Grand Total - £1939 - saving you £936.

You're welcome.

But you don't quite the same thing. Cadence vs torque sensors, for example. One is cheap, other is better. and more expensive. Cadence sensor on the Swytch does look like a bit of a joke, too.

So many e-bike conversion kits have such a level of dodgy-ness about them. I'm of the belief that when it comes to e-bikes, it's really better to get something that's been designed around having 250W (and let's face, there are plenty doling out more), and delivering it sensibly and safely, than having some examples of the likes of deliveroo (other brands apply) guys flying along at 25mph+ (one I guy his chain was broken, so zero pedal action), that are clearly not safe for rider or other road users, as other than adding a load of power, nothing else has been upgraded. While decent cat B or A guy would put out more power, they have full control over it.

Many reputable bike brands have put a decent amount of R&D into creating e-bikes that provide the assistance than people want, while being safe with the additional power provided. They have reputations and safety records to maintain. Whereas, any conversion kit supplier has a bunch of excuses when it comes to the installation, the condition of the bike installed to, who installed it, etc.

I think it's time for people thinking about converting their bikes to think about donating their bike to someone else that'll use it unconverted, and just get a new, decent, e-bike, designed and manufactured for the job. I've not ridden an e-bike yet... I'm saving it for while. But I like the idea of having one for recovery rides, that links to heart-rate monitor, so that helps me keep below heart-rate zone.
 
OP
OP
Y

yoho oy

Active Member
It seems that brompton kits sell for around £300 on aliexpress. From the way they wrote posts there it is hard to understand is that with a battery or without. I think buying in spare parts could be cheaper - motor, spokes, controller. The key is knowing what fits what.
 

Kell

Veteran
I've not ridden an e-bike yet... I'm saving it for while. But I like the idea of having one for recovery rides, that links to heart-rate monitor, so that helps me keep below heart-rate zone.

My wife has an e-bike. I don't think it would help with a recovery ride any more than a normal bike with an HRM.

As the old saying goes, it never gets any easier, you just go faster. What I've found riding her bike is that you're unaware of the assistance and pedal just as hard as you would on a normal bike - it just feels like you've got the wind at your back. The only time it makes a noticeable difference in effort is on the hills. You still seem to put in the same amount of ooomph (for want of a better word) but the additional help means it's over quicker.

I can't speak for all systems, but hers works really well. (Cannondale Quick Neo)
 
But you don't quite the same thing. Cadence vs torque sensors, for example. One is cheap, other is better. and more expensive. Cadence sensor on the Swytch does look like a bit of a joke, too.

So many e-bike conversion kits have such a level of dodgy-ness about them. I'm of the belief that when it comes to e-bikes, it's really better to get something that's been designed around having 250W (and let's face, there are plenty doling out more), and delivering it sensibly and safely, than having some examples of the likes of deliveroo (other brands apply) guys flying along at 25mph+ (one I guy his chain was broken, so zero pedal action), that are clearly not safe for rider or other road users, as other than adding a load of power, nothing else has been upgraded. While decent cat B or A guy would put out more power, they have full control over it.

Many reputable bike brands have put a decent amount of R&D into creating e-bikes that provide the assistance than people want, while being safe with the additional power provided. They have reputations and safety records to maintain. Whereas, any conversion kit supplier has a bunch of excuses when it comes to the installation, the condition of the bike installed to, who installed it, etc.

I think it's time for people thinking about converting their bikes to think about donating their bike to someone else that'll use it unconverted, and just get a new, decent, e-bike, designed and manufactured for the job. I've not ridden an e-bike yet... I'm saving it for while. But I like the idea of having one for recovery rides, that links to heart-rate monitor, so that helps me keep below heart-rate zone.

Wouldn't it be easier and cheaper to just take it easy and choose flatter routes for the recovery rides ?
 

mitchibob

Über Member
Location
Treorchy, Wales
My wife has an e-bike. I don't think it would help with a recovery ride any more than a normal bike with an HRM.

There was that Merida bike that was used on a recent GCN commuter challenge that apparently does it, although I did wonder if using on a group ride, it could be more fun to have it linked to someone else's heart-rate monitor on climbs.

As the old saying goes, it never gets any easier, you just go faster.

Yeah, but age is definitely starting to work against me, and even Greg Lemond has released his own e-bikes!
 
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