Brompton - Crystalite 209 Motor

[Herb]

Jerry

I think the batteries you propose to use are probably the better technical solution but I have no patience and needed a battery without the hassle of building it myself.

From reading I believe the Bosch will be more reliable than Dewalt in the supplied battery form but not when stripped down and reconfigured by an enthusiast.

I am waiting for the charger to be delivered, as the battery was delivered not fully charged.

Herb

 

[daniel.weck]

I came across this comment from Bike-Forums.net:

"
The Crystalyte 404 hub motor is well matched to a 16" wheel. I run one on an old Rebike steel recumbent (front motor) at 48 Volts and it is very fast. I am able to cruise at 24mph on it. The 405 is matched to a 20" wheel, and 406 is matched to the 26" wheel. As noted earlier the rpm/volt varies, and in this case the 404 has 4 windings, which is faster than the 405 which has 5 windings. The 404 has a higher rpm per volt. So the 404 in a 16" has about the same torque as a 405 in a 20" etc., as the higher rpm per volt is offset by the smaller wheel size. I like this motor - I would use an Aotema sensorless controller on it, to avoid issues with Hall sensors in wet environments. The rebike runs great. You need a 100mm dropout width. The motor was tightish on the spacing but had 2mm clearance on either side of the motor, to the forks. Check your engineering diagrams. I also run a 404 on a 16" Bridgestone Sneaker City folding bike.
"

Cheers, Dan

 

[jerrysimon]

I came across this on youtube as well

YouTube - Brompton met een Crystalyte kit (montage)

Battery looks rather big and ugly in that position. The controller seems well placed though.

Regards

Jerry

 

[Herb]

I need to stop reading posts and do some work today, unfortunately I am addicted.

One of the reasons I am interested in ParameterDesigner as discussed in “Can I get more power from my 36V 250W Bafang (10Ah battery)” post.
Is because I think I need a more powerful controller on my Brompton.

I intend to contact Frank to see if is possible to use one on his controllers to boost to low torque on my Crystalyte direct drive motor, I would then like to experiment with settings and with luck raise the current threshold perhaps from 10 to 15A.

The drive is very enjoyable at higher speeds but needs more low down grunt.

Herb

 

[Herb]

CONTROLLER

After using the Brompton I feel I am happy with the controller now and will not try to increase the power.

RANGE OF BATTERY

I have now carried several test rides on my Brompton with the Bosch 2.6 aH battery.

I can ride to 5 miles to the city of Wells using the throttle only on inclines. The return, generally a more challenging slow uphill with more motor assistance (but pedalling all the way) leaves me 300m from home with a flat battery.

Unless I am ridding very short journeys of a few miles I need more confidence that I can complete the round trip - Yes I know I could Pedal !

I have contacted and ordered two Ideal Diodes from Tiberius and now intend to use my other Bosch drill battery in parallel to achieve 5.2aH. This will make the total battery weigh 2.6Kgs.

I am very pleased with this flexible battery solution.

Herb

 

[jerrysimon]

Thanks for the update Herb.

I keep meaning to do a post on my Brompton which arrived late last week finally. I am still awaiting batteries and bits to turn it into an "E" though.

Regards

Jerry

 

[Herb]

Nearly the final layout.



I have shortened the controller cables and attached the controller to the main tube. All the unused cables have been disconnected.



The battery/or batteries now fit on a Brompton luggage block/cut down rack and the connection made with Anderson Powerpoles.
I am presently making a slotted frame to take one or two batteries this will attach to the luggage block and sit inside a small bar bag for protection against rain.


The folded bike ready for transport.

Herb

 

[jerrysimon]

Nice job Herb

Regards

Jerry

 

[NRG]

Yes, very neat installation, good job!

 

[daniel.weck]

Lovely !
That controller is so small !

 

[Herb]

GETTING NEAR

I have now wired two Ideal Diodes to combine my Bosch batteries in parallel.

I have made a guess at the size of the heat sink. This needs to be capable of 12A - the current drawn if only one battery is fitted, normally only 6A on each battery.


One of a pair of Ideal Diodes, puchased from Tiberius, attached to 3mm copper bar as a heat sink

Perspex frame to hold two Bosch 36V 2.6aH batteries sat inside the frame of a Creek2Peak 16L bag

Interior view showing one of the diodes behind the perspex

Showing the Rixen Kaul Klickfix adapter on the back of the bag

Modified Brompton carried with cut down Klickfix bar adapter attached

I am getting near the finished product, I will only need a further year of "Tinker Time" to actually get to the finished product.

If Tiberius is watching - let me know your thoughts on the size of the heat sinks, I have said 12A but if I use this pack on my other bike I need to be able to handle ( worse case ) 17A on one diode.

My thanks to Daniel Weck and Jerry Simon, The Brompton Trail Blazers, Both an inspiration to myself and hopefully others.

I have not commented on their builds in the past, but will do so in the future.

Herb

 

[Herb]

GETTING NEAR (page two)

Only 5 pictures allowed on previous post

Final Pictures





Herb

 

[jerrysimon]

Some very neat work Herb.

Today must be battery building day, as I have just come in from my workshop having built my first pack of six cells which are the same ones used in DeWalt 36V packs.


Regards

Jerry

 

[daniel.weck]

Beautiful work !

I'm seriously considering getting 2 or 3 Bosch 36V BAT836 battery packs, as
they are small (2.2-2.6Ah each) but suitable for high C discharge rate.
Each pack contains 20x Konions (10s2p), which are Samsung or Sony 18650VT cylindrical cells. Each cell's rated capacity is 1.1Ah for 4.1V charge, or 1.3Ah for 4.2V charge but with limited cycles (decreased battery life).

Just like you, I don't particularly want to dismantle the packs, I just want to adapt the charging input and the discharge output. Can you give us some tips as to how to plug into the existing socket, and what kind of charger to use ? (other than the expensive Bosch charger)

Apparently the charge voltage cut-off with the regular Bosch charger is 40.5v, that probably helps the cells to self-balance, or at least to avoid drifting (the Bosch fast-charger pushes 41V, and the recommended limit is 42V when using regular generic chargers).

Many thanks !!
Regards, Daniel

 

[Herb]

Daniel

I am pleased with the Bosch 36v packs – or Fatpacks .

The only flaw in the my plan is I took them apart to solder the leads to the Anderson Poles. They can never go back if they fail under warranty.

If you look on the second picture of my post of today you will see the two wires exiting from the black rubber casing.

Now that I have my Perspex mounting frame it would be possible to arrange metal blades to engage with the contacts in the battery but I have only just finished its construction.

I use the Bosch charger, it has an internal fan to cool the battery if it detects high temperature.

On Ebay it is possible to buy a graded Bosch Rotak Lawnmower, This has a Battery, Charger and a Docking station for the battery in the mower itself. – Throw the mower away when have gained the parts. - or make a new helicopterbike with its motor.

It appears in the list if you search “Bosch 36v” in Ebay

This battery compartment is also listed as a spare part on the Bosch website. But as yet it is unavailable as I tried to buy one.

If you are starting from scratch, I believe Jerry Simond’s A123 pack is a good solution but I am sure you are already considering its merits.

Herb

 

[daniel.weck]

Thanks a lot Herb !

 

[Herb]

A single Bosch 36V 2.6aH battery when fitted with the Radio Flyer “Tassels Blowing in the Wind” regeneration system will power a small trike for an entire childhood



Herb

 

[daniel.weck]

Great ride Herb ! The Brompton, now this one....how tall are you ??

 

[bikes2fold]

Spokes

Hello, just found this forum. I am planning on building a Brompton with the 209 motor. I am just wondering which spokes (length) you have used. I hope you receive a notification so you will be able to reply.

Greetings from Holland.

 

[jerrysimon]

Welcome to the forum

Best thing to do is to measure the rim and hub and use a spoke calculator like this one here

If you click help on the left it will show you what to measure.

PS pulling up this thread I must admit I have not seen Herb post for some time

Regards

Jerry