The d8Brompton: converting and upgrading an old Brompton

AndyOfTheSouth

Esteemed Pedelecer
May 15, 2009
347
4
Non-Bromptonians may wonder why the bike has such a following. First time you ride one, they feel very twitchy and even a bit unstable. When you get used to the ride, it is fun and strangely addictive. It is particularly useful about town. But it does have limitations compared with a full-size bike. It has become so popular because of the compactness and rapidity of the fold. It is the only folder I would consider taking on public transport (I have two other folding bikes). Apart from going by train or tube, it is so compact that it takes up little room in the car or by the door, so it is always available. It's this utility which helps justify its expense, which is significant, together with it being very durable and having all spare parts on call (again at some expense).

However, impressive thought these virtues may be, however, they do not help the rider up a steep hill, which is where d8veh comes into the picture. He kindly offered to convert an old Brompton of mine. The key requirement for me was that it should be a good hill climber and, when converted, it should still be rideable as normal without power. Also, I wanted it to be robust enough for rough ground and as light as possible. There was no requirement for assistance at speed or for a long range.

d8veh's superb conversion has put the battery and controller in a streamlined, colour matched case attached to the top tube. The cabling is very neat and there is no interference with the fold.

The ride is completely unaffected by the conversion. Riding unpowered, which I do most of the time, the Brompton is exactly as normal. When the motor is switched on, power delivery is very smooth. Hill climbing is excellent, allowing a 12% hill to be scaled with little effort.

I'll jot down some notes later on the non-electric aspects of upgrading and d8veh will describe the technical aspects of the electric kit.
 
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patpatbut

Esteemed Pedelecer
Apr 25, 2012
860
79
Non-Bromptonians may wonder why the bike has such a following. First time you ride one, they feel very twitchy and even a bit unstable. When you get used to the ride, it is fun and strangely addictive. It is particularly useful about town. But it does have limitations compared with a full-size bike. It has become so popular because of the compactness and rapidity of the fold. It is the only folder I would consider taking on public transport (I have two other folding bikes). Apart from going by train or tube, it is so compact that it takes up little room in the car or by the door, so it is always available. It's this utility which helps justify its expense, which is significant, together with it being very durable and having all spare parts on call (again at some expense).

However, impressive thought these virtues may be, however, they do not help the rider up a steep hill, which is where d8veh comes into the picture. He kindly offered to convert an old Brompton of mine. The key requirement for me was that it should be a good hill climber and, when converted, it should still be rideable as normal without power. Also, I wanted it to be robust enough for rough ground and as light as possible. There was no requirement for assistance at speed or for a long range.

d8veh's superb conversion has put the battery and controller in a streamlined, colour matched case attached to the top tube. The cabling is very neat and there is no interference with the fold.

The ride is completely unaffected by the conversion. Riding unpowered, which I do most of the time, the Brompton is exactly as normal. When the motor is switched on, power delivery is very smooth. Hill climbing is excellent, allowing a 12% hill to be scaled with little effort.

I'll jot down some notes later on the non-electric aspects of upgrading and d8veh will describe the technical aspects of the electric kit.
Would you mind to share some photos of the build?

Thanks
Pat
 

D8ve

Esteemed Pedelecer
Jan 30, 2013
2,142
1,294
Bristol
This looks like a fab idea, it's from the USA, and I think the power is to high for us here in the uk and I'm not sure what the cost is or if you can even buy one here.
Www.shareroller.com
Limited power, slips in the wet, wares the tire.
It's been tried many times and it's never been a winner .
 
D

Deleted member 4366

Guest
Q85 motor gives plenty of power for a small-wheeled bike. S06S controller with S-LCD3, pedal sensor and throttle. the custom 35v 8aH battery came from Insatinternational. It has cells with a very high discharge rate in a 10S3P confuguration. The whole kit is about 4.5kg.

I was hoping Andy could show some photos of it out in its natural environment.







 

AndyOfTheSouth

Esteemed Pedelecer
May 15, 2009
347
4
Much enjoying the bike. As much fun to ride pedal only as a non-electric Brompton, but the motor is such an advantage up hills. This means that trips which I wouldn't otherwise do are simply very enjoyable. All the pleasure of cycling amidst the hills without the pain. Here's an example of a ride on the western edge of the Brecon Beacons.

AmongWestWalesHillsLowRes.jpg
 

AndyOfTheSouth

Esteemed Pedelecer
May 15, 2009
347
4
Hmmm. What is the best resolution to use when uploading a photograph?

Edit: Ah, I see. It appears OK when signed in...