Brompton - Crystalite 209 Motor

[Herb]

Brompton - Crystalyte 209 Motor

I am building a Brompton powered by a Crystalyte 209 motor fitted in a 16 rim
So Far
Already own the Brompton
Waiting for 36V 10ah battery from Ping - PingBattery LiFePO4 Battery packs for Electric Bicycle e-Bike & Scooter, Lithium Iron Phosphate Battery
Waiting for Crystalite 209 motor from Crystalyte Europe
Delivered - Hyundai 100 pc aluminium CD case as daniel.weck - for the battery (thank you)
Will keep the Forum of my progress in exchange for help along the way

 

[jerrysimon]

Herb,

Interesting project and one I will follow with interest

I thought about a similar setup but have decided to go for a Tongxin 36v 240rpm motor to save weight. Likewise for a battery I am planning on a lightweight option of 12 * a123 batteries but will only have 2.3ah for my short 5 mile commute each way to work. This will probably mean I will require a second charger at work.

Regards

Jerry

 

[daniel.weck]

Interesting

Let us know how it goes !
Cheers, Daniel

 

[Herb]

Everything arrives at once.
Hub motor from Crystalyte.
Tube and Schwalbe Marathon Plus from St John Street Cycles.
Battery from Ping.
First. Charge battery .

The hub is quite heavy, complete wheel with tyre weighs 4970 grams. The original Brompton Wheel was only 954 grams on my kitchen scales. The wheel fits into the forks but needs a 3mm spacer on one side to centralise the motor.
The twist hand throttle replaces the right hand grip, this is the only control as the pedal sensor will not be connected.

Battery is packed into the CD case, then the case and Controller fit inside a handlebar bag that I strap to the Brompton handlebars.

Test Drive – Fixing strap of bag rips open but battery hangs on and is not damaged.
Bag is now tied to rear seat/post as a temporary measure.

First impressions are good, Quiet, there is some vibration when pulling at low speed – I think this is to be expected on a direct drive motor

Will report after I have ridden a few miles.

Herb

 

[NRG]

We need pictures!

 

[jerrysimon]

Pictures!

I second that.

These projects are meaningless without pictures

Regards

Jerry

 

[Herb]

I second that.

These projects are meaningless without pictures

Regards

Jerry

patience is a virtue

It is hard to receive the parts, assemble the parts, ride the bike and take pictures in only one evening

Pictures will follow

 

[Herb]

Battery now fitted to new front rack , Not sure about this position, may have to buy rear rack, but this is better than last nights tape and string method

View of hub

Motor and sensor plugs

Steel spacer to centralise wheel in fork, White washer is part of hub. It looks twisted but this is camera angle !

Twist throttle, spring loaded, no other controls

No chance to ride yet

Herb

 

[jerrysimon]

Herb,

Great job!

Thanks for posting the pics.

I very nearly went for the Crystalite 209 Motor myself as its just plug play i.e. no messing about with widening forks and its readily available!

Regards

Jerry

 

[monster]

you should limit the controller to 15amps and don't run full throttle all the time. thats a great motor but the ping battery is only good for 1-1.5C although great capacity for the money. you should get a power meter to check how your treating the battery. or at the very least wire some bike lights that run off the battery and make sure they don't dim too much when you accelerate! nice build tho. ideal for the train.

 

[daniel.weck]

Enjoy your ride, congratulations for your purchase!

 

[Herb]

Thanks for the advice Monster, The Crystalyte CTPL-JNYF-3612 controller I have used is rated at 12 amps.

On Saturday I will have time to ride the bike and be able to use a DC clip on ammeter to measure the current.

Herb

 

[georgesign]

I too fitted a hub motor to my Brompton. Unfortunately there were problems which I will not go into as they are best kept between the supplier and myself. The reason for this post is to say what a wonderfully designed bike the Brompton is. I only really realised this when I converted it back to a standard bike. My advice, for what it's worth, is don't mess with this little "gem". In my opinion, fitting a motor and battery destroys the charm of the Brompton. Put the money towards a really good ready made electric bike.

 

[jerrysimon]

georgesign,

I read the earlier post re your kit and glad you got it sorted out.

I will hopefully get my new Brompton next week, but still plan to fit a DIY Tongxin and small light battery to it.

Regards

Jerry

 

[flecc]

My advice, for what it's worth, is don't mess with this little "gem". In my opinion, fitting a motor and battery destroys the charm of the Brompton. Put the money towards a really good ready made electric bike.

Keen Brompton fans the Henshaw family of A to B magazine fame seem to be of a like mind. Although David Henshaw collaborated in the original Nano-Brompton design and is full of praise for it, they've kept their three family Bromptons unpowered.
.

 

[daniel.weck]

The reason for this post is to say what a wonderfully designed bike the Brompton is. I only really realised this when I converted it back to a standard bike. My advice, for what it's worth, is don't mess with this little "gem". In my opinion, fitting a motor and battery destroys the charm of the Brompton. Put the money towards a really good ready made electric bike.

I kind of agree with you. However, a Bafang (or even better: a Tongxin) will not ruin the Brompton experience as much as a Crystalite (due to smaller size and weight).

I think that those who can afford (in terms of money and storage space) to own a Brompton as well as a full-size pedelec/e-bike => go ahead and do it

My budget being what it is, and due to the lack of space at home, my e-Brompton is just a totally perfect solution and I can't see any other folding bike that would meet my requirements as well as the B !

It's such a great folding design. The more I work on the bike, the more I realize how tiny the margins are to get it to fold so neatly. It took a great idea and a lot of creative thinking to achieve such a well-balanced grow-up bike (i.e. not a silly useless midget folding bike).

So yes, I can't flick-fold my Brompton like I used to, but all the other great benefits are still here and I enjoy them thoroughly !

Dan

 

[Herb]

My advice, for what it's worth, is don't mess with this little "gem". In my opinion, fitting a motor and battery destroys the charm of the Brompton. Put the money towards a really good ready made electric bike.

Both Flecc and georgesign are correct. It is a travesty to put a front wheel weighing 4 Kgs more than the original into a superb light and well engineered Brompton frame.

This is the rub - if you have to modify it is best to modify the best. With more resource I would have a virgin Bropmton and motorised Brompton.

As for a review - I can report the direct drive motor has little torque but a great deal of speed if you are prepared to pedal ! Yes it will climb hills but you need to work.

I wanted an assisted folding bike that I did not need to modify (keep the original forks and could return to original wheel) , could transport in the back of a mini, unfold and ride and I think I have achieved my quest.

I would still be interested in the 80mm tongxin motor if they were freely available.

Herb

 

[AndyOfTheSouth]

Herb - you might look at the group purchase scheme for Tongxins being floated on the other thread.

Georgedesign - glad you got a good resolution to the problem.

Generally - I think the Brompton/motor issue has two parts.

The Tongxin benefits from a small wheel (less load, fewer breakdowns, better hill-climbing).

The Brompton benefits from a Tongxin because it is the lightest (also the less resisting, but that applies to all wheel sizes) and therefore most suitable to a bike designed to be carried as well as ridden. However, the motor and especially the battery add weight which is to some extent contrary to the carrying aspect.

This is a somewhat roundabout way of saying that you would only motorise a Brompton if you really need to for commuting via train, or make use of its small wheel size to either climb hills or coddle the Tongxin.

Otherwise, you'd be best off leaving it as it is and having another ebike, which is what George has concluded.

In the words of Barnowl (I think)... I'll get my coat.

 

[Herb]

A number of post are now looking toward a smaller battery and I have now connected a power tool battery to my Brompton

Bosch 36v 2.6 ah Battery

1272 grams

In small plastic case with controler

I have seen the same battery used in pictures in previous posts.

If I lock the brakes and stall the motor the current I measure is only just over 11amps. The controller cuts out at this threshold.

This gives a discharge of just over 4C and I believe the battery is well within its capabilities as it is used in a 600W drill and a cordless mower.

As for the range I will test latter when the battery is fully charged.

Lets hope for 8 or 9 miles.

Herb

 

[jerrysimon]

Herb,

Excellent work and great to see pics! Look forward to hearing about your range. In my case I am looking at about 11 miles, would be perfect as that is my daily commute there and back. When I build my A123 pack if this is not enough I will leave a charger at work.

I did look at these tool power packs but I thought the built in BMS limited the current draw unless you fit a specially circuit ? Certainly that is the issue with Dewalt 36v A123 packs which are also VERY expensive.

Regards

Jerry