EZ Rider Brompton Kit

[Chris.mitu]

I just got around to installing the EZ Rider Brompton kit on my 2012 H6L Brompton and took it for a short test ride.

Some specs from the Internet:

• 36V 7Ah high power LG cell lithium battery
• 36V 14A smart FOC controller and a TFT colour LCD display
• Kit weight 3.8kg
• 250W brushless geared hub motor
• 36V 2A charger
• PAS cadence sensor

I initially ordered the Swytch Air Max kit with the Black Friday Discount but then costs started to mount up for additional basics such a brake sensors, a non basic display, luggage mounting point adaptor. This and the 1-2 month delivery date caused me to change my mind.

I bought the EZ Rider Brompton kit from moddsebikes.co.uk . They were very responsive both on Ebay and on their Facebook page.

The kit is meant to be installed on the handlebars. My main concern was that once mounted on the handlebars it would prevent the bike from folding fully. Despite reasurances that if you remove the battery and flip up the handlebar mounts it would fold fully I wanted to mount it lower on the frame on the luggage mount point on the Brompton. I found a few Swytch Brompon adapters on Thingiverse and took take a chance on it fitting this kit and order a 3d printed Brompton luggage mount adapter from Ebay and a PAS sensor adapter for 19GBP.

www.thingiverse.com/thing:4860589 - Swytch mount adapter
www.thingiverse.com/thing:4861507 - PAS


I found the EZ Rider kit cheaper on their online store than on Ebay. Delivery was very quick.

The kit is very well packaged. It was very easy to install.
The 3d printed Swytch adapter took some mimimal shaving off to make the EZ Rider handlebar mounts fit.

I had to angle the hadlebar mounts slightly upwards to prevent them fouling the back of the battery and PAS connectors when steering.



The fold is unnaffected by the kit and I don't have to remove the battery for a full fold. I don't recall the weight of the kit but the bike still feels nearly as easy to carry folded with the battery left in place.



Unfortunnately the brake sensor cables are approx 65-70cms too short and I willl have to find or make extension cables. I didn't install them for now. If anyone knows if the connectors are standard please let me know.


The test ride was great. While pedalig the bike I can see the display on the battery clearly although it is mounted further down on the luggage mount rather than the handlebars. The only imitation is not being able to adjust the assistance level while riding it.

I couldn't feel the motor working on assistance level 1 but on 2 and 3 there is definitely a kick easily spinning faster than my legs in gear 1 and 2

I've not done a range test but I did see a video on Youtube where Andy Kirby did a test range and he said he got 17-20miles.

 

[Chris.mitu]

A couple of photos of somebody else's Brompton with the EZ Rider kit installed as designed.

 

[StuartsProjects]

Nice conversion and not expensive at all. Like the searchlight on the front.

As you have discovered if you want to be able to fold the Brompton, and wheel it around, without taking the battery\controller off, it does need to go on the luggage block.

Shame they used that relativly uncommon Julet connector for the brakes when the normal round ones are so easy to find.

 

[AntonyC]

Those are called shaped ebike connectors, although extending the wire is another option.

Durable Extension Cord Shaped Cable Ebike Electric Bike Julet Connector | eBay

Julet Connector. Ebike Shaped Connector 2/3/4/5/6 Pin Cable Waterproof Connector Signal line. 1 x Extension cord. This is THE best option for having water tight connections on your e-bike. RED = 2 PIN.

www.ebay.co.uk

A pair on eBay will set you back £9, on AliExpress £3.80 to Europe but not available to the UK. See

Kunteng (KT) brand reduced shipping to the UK from Aliexpress

Hello, I bought a bunch of KT stuff on Aliexpress a while back and have gone back recently to buy another controller. I've found that most of the sellers are unavailable to send a KT controller to the UK. If I VPN to the US and select US for shipping I see the product availability just like...

www.pedelecs.co.uk

 

[mta102]

I'm considering getting this kit too. My problem is that I would need to carry my Brompton abroad (Def not possible with the 36v 7ah = 252 Wh battery, as the hand carry limit is 160 wh). Has anyone explored separating the battery and the controller, so it would become possible to connect it to an alternative battery?

 

[AntonyC]

The Batteries section in these CAA regs begins What is a lithium battery? so it seems fair to ask What is a Brompton? If it's a Mobility Aid for disability, health or age the limit's 300 Wh, better still if it's Lithium battery-powered equipment capable of generating extreme heat it seems to suffice to remove the fuse whatever the capacity (see Items Containing Batteries), in either case needing the airline's approval. Who knew? Usual disclaimer, I've only looked at that and these IATA regs.

 

[Chris.mitu]

Is the motor supposed to be considerably louder when riding the bike vs when the motor is spinning free. I only just noticed today and I don't think it was as loud when I first got it.

My Fido d11 doesn't have much of a change in sound whether I am on the bike or off with the motor running.
https://youtube.com/shorts/UAErF83BkAg?si=fsFxlgGn0vV0Kolx

 

[saneagle]

Is the motor supposed to be considerably louder when riding the bike vs when the motor is spinning free. I only just noticed today and I don't think it was as loud when I first got it.

My Fido d11 doesn't have much of a change in sound whether I am on the bike or off with the motor running.
https://youtube.com/shorts/UAErF83BkAg?si=fsFxlgGn0vV0Kolx

Yes. Most of the noise comes from the commutation pulses. With the motor under full power at low speed, it can sound and feel like gears grinding. Most motors are quiet wwhen spinning with the wheel in the air because there is no load and the speed is high, so you can't resolve the commutation pulses.

Factors that affect noise:
1. Sine-wave controller is much quieter than a square-wave one - motor is pushed round rather than knocked round
2. The motor's winding speed. Faster ones are more noisy at low speed than low-speed ones. fast motors have lower reduction ratios and less efficiency at low speed, which means slower commutation and bigger pulses.
3. The amount of current the controller allows - bigger communtation pulses.
4. Position of the motor. Front ones are always annoyingly loud compared with rear ones. It's just the way that the sound comes at you - the way you perceive it.
5. The motor's internal reduction ratio. High reduction ratios are quieter than low ones - commution frequency higher and load on motor lower.

4 is probably the biggest factor for perceived noise, but any of the others can change the sound drastically.

 

[Chris.mitu]

Yes. Most of the noise comes from the commutation pulses. With the motor under full power at low speed, it can sound and feel like gears grinding. Most motors are quiet wwhen spinning with the wheel in the air because there is no load and the speed is high, so you can't resolve the commutation pulses.

Factors that affect noise:
1. Sine-wave controller is much quieter than a square-wave one - motor is pushed round rather than knocked round
2. The motor's winding speed. Faster ones are more noisy at low speed than low-speed ones. fast motors have lower reduction ratios and less efficiency at low speed, which means slower commutation and bigger pulses.
3. The amount of current the controller allows - bigger communtation pulses.
4. Position of the motor. Front ones are always annoyingly loud compared with rear ones. It's just the way that the sound comes at you - the way you perceive it.
5. The motor's internal reduction ratio. High reduction ratios are quieter than low ones - commution frequency higher and load on motor lower.

4 is probably the biggest factor for perceived noise, but any of the others can change the sound drastically.

Thanks for the detailed response. My concern comes from only observing the noise now after a month of ownership when the running noise under load was about the same.

 

[RollingChunder]

Yes. Most of the noise comes from the commutation pulses. With the motor under full power at low speed, it can sound and feel like gears grinding. Most motors are quiet wwhen spinning with the wheel in the air because there is no load and the speed is high, so you can't resolve the commutation pulses.

Factors that affect noise:
1. Sine-wave controller is much quieter than a square-wave one - motor is pushed round rather than knocked round
2. The motor's winding speed. Faster ones are more noisy at low speed than low-speed ones. fast motors have lower reduction ratios and less efficiency at low speed, which means slower commutation and bigger pulses.
3. The amount of current the controller allows - bigger communtation pulses.
4. Position of the motor. Front ones are always annoyingly loud compared with rear ones. It's just the way that the sound comes at you - the way you perceive it.
5. The motor's internal reduction ratio. High reduction ratios are quieter than low ones - commution frequency higher and load on motor lower.

4 is probably the biggest factor for perceived noise, but any of the others can change the sound drastically.

Thanks for this saneagle it explains the noise I'm hearing up hills.

The noise stops if I slow down a little, am I damaging the motor if I keep full power up hill and make the grinding noise?

 

[saneagle]

Thanks for this saneagle it explains the noise I'm hearing up hills.

The noise stops if I slow down a little, am I damaging the motor if I keep full power up hill and make the grinding noise?

No, not with a motor in a 16" wheel unless you're less than 3mph.

 

[RollingChunder]

No, not with a motor in a 16" wheel unless you're less than 3mph.

Sorry I was hijacking the thread. Wheel is 26". Presumably, the motor heats up until failure so as long as I keep an eye on temperature, grinding noise isn't a problem?

 

[saneagle]

Sorry I was hijacking the thread. Wheel is 26". Presumably, the motor heats up until failure so as long as I keep an eye on temperature, grinding noise isn't a problem?

Motors don't like to go slow. It damages the gears and heats everything up. If you don't have enough power to keep the motor spinning to say 8 mph, it's probably a good idea to turn the current up a bit.

It's counter-intuitive, but the extra current spins the motor faster, directly in proportion, but if you don't have enough power and the motor slows down, the heat goes up exponentially, so a small change in current and speed can make a big difference to the overall heat, even though you make a bit of heat due to the extra current. Basically, what you save is a lot more than the extra you make.