Dynamo diatribe

I've just realised that I've been posting most of my Tour Aotearoa stuff on my Instagram instead of my blog, which is pretty hopeless as far as being a resource for anyone else who may be interested.

See below a graphic timeline for creating my "charging regime" for the Tour Aotearoa Brevet.

I started with an Exposure dynamo Light, I saw a great deal on Evans cycles and picked it up for around $350 NZ plus $20 shipping. A light AND the Exposure branded SP hub. That is very cheap. It was an impulse buy. It is a 9mm QR hub with 28 holes, possibly why it was cheap, with through-axle being more in demand these days for some people, and 28 holes being more suited to a road application than off-road.

I got a new rim and spokes and Francis at Jville Cycles built up the wheel.

It was great. I had free light for as long as I could pedal! But this was just the beginning. Nathan Mawkes told me what he did for his Kiwi Brevet charging regime, and as it was a very cheap option I followed suit. Even cheaper than Nathans option. I brought a 10 US$ torch, and an 8 US$ charger/power-bank, with a couple of 18650 (Chinese) rechargeable batteries thrown in.

I ran some tests. This torch is very bright. It has high, medium, and low modes plus a few more. It lasts for 3.5, 7 and 14 hours respectively.

18650 batteries are what is found in lap-top cases. I almost started a fire breaking one up. If you do this, exercise caution.

These are unprotected cells. Don't put them on charge and go out for the day!  The good ones are about $18.50 each NZ from MrPositive (if you cant gut an old lap-top without maiming yourself then buy the Panasonics).

You will need a way to charge these batteries, as your dynamo won't do it "out-of-the-box" . You need a USB-converter, the Sinewave one is good, but not cheap.  I got Kerry at kLite to build me a switch as well so I could easily toggle from lights to USB charging.

The plan goes like this:
1. Start with about 3 fully charged 18650 batteries.
2. Use one as a cache-battery inline between my dynamo and my "device" be it GPS or phone.
3. In the evening, I can also use one of the batteries as back-up in the spare torch which I can strap to my helmet.

The cheapie charger/power-bank allows "pass-through-charging" which you need if you are going to be charging and being charged at the same time.

The white thing inline here is just temporary. It is measuring the load from my GPS.

A rather crowded dash-board.

All of the gizmos will fit in here. A Stealth Bike Bags top-tube bag.

So far my testing has been pretty minimal. But I can say this.

It all fits.
I rode around the bays the other day and charged my phone from 5% to 72% in about 1.5 hours.

Isn't all this TECHNOLOGY risky?
Of course.

The fall-back plan
I will take a spare USB cable for my phone.
This is also spare for charging my power-bank device.
I will take a 3 pin USB plug and a tiny 3 port hub to plug into it, should my dynamo explode leaving me with no electricity, forcing me to charge in a motel or such-like.
I will take my original dynamo light harness as a spare in case my switch/harness gets damaged.

Basically if I have a "power-transmission" outage I will be USB charging my batteries, phones and light from 3 pin plugs. 3 x 3.5, 7 and 14 hours is a lot of light. This is what most people will be doing anyway, it's just my back-up.

That's the theory anyway : )

Bright but cheap torch
http://www.lights-box.com/ultrafire-wf-501b-cree-xm-l-t6-1000-lumens-5-modes-led-torch-1-x-18650-battery

Basic power-bank/charger
https://www.fasttech.com/product/1137904

Tester gizmo
http://www.dx.com/p/lcd-display-usb-power-charger-data-transmit-current-voltage-tester-capacity-tester-white-315314#.Ved5f5cUe80


PS. Don't burn down your house messing around with this stuff.
If I told you to jump off a cliff would you?
Exactly.

Read More

Dynamo lighting 101. Part 1

I have recently set up a bike with a dynamo hub for use in the Tour Aotearoa and while it's all fresh in my mind I will share the basics so you might find it easier than I did. There are many resources out there but a lot of them assume you know more than you do.

A few disclaimers from the start.

1. Dynamo lights are not magic, and as far as I know, they only come with bike mounts, as opposed to helmet-mounts. You cannot ride singletrack fast with a bike mounted light alone. Optimally you would also have a helmet mounted light for seeing around corners. Obviously for commuting a bike mounted light is more than enough. This post is angled at a "bikepacking" end-use (although commuting is a no-brainer for dynamo lighting).

2. When the going gets slow, your dynamo light will put out a lot less light than you would expect from a typical battery powered light, depending on your set-up and how fast your "slow" is, this is why people will often run a spare light-weight helmet mounted light.

How dynamo power is typically used

Lighting only
Requirements: Dynamo and light

Lighting and/or  powering
Requirements: Dynamo, light and usb converter (and a device to power; eg Phone, GPS etc)

Lighting, and/or powering and/or storing power
Requirements: Dynamo, light, usb converter and a power-bank/battery (and a device to power).

Handlebar switch from kLite

A fourth scenario is to have all of these things working with a switching system. Kerry at kLite builds these to order and probably knows more about dynamo lighting in relation to bikepacking than anyone out there. A switch means that you don't need to stop and unplug and replug devices.

Some jargon

What is a standlite?
A smaller battery or capacitor built into or attached to the light so that the lighting does not disappear immediately you stop moving. Many dynamo lights have them built in.

Sinewave USB converter

What is a USB converter?
This device changes the current from the dynamo from AC to DC so that it can be used to charge devices like GPSes, smart phones, cameras or power-banks (batteries). A very popular device seems to be the Sinewave for bikepacking needs. Another popular choice is the Ewerks.
A well researched list of hub-dynamo USB converters is available here.
Some very good instructions on building your own converters can be found here, and here, just don't ride too fast and make them explode. (This could happen - read ALL the comments : )

What is a cache battery?
It's just a battery/power-bank you run inline, after your usb-converter but before the device you are powering. Eg.If your GPS sends up a nag screen saying "lost power" because you are riding slowly up a steep hill and not generating enough power, the cache battery, (if it has some charge in it) will supplement the GPS and stop the nag screen. The rich kids will use an Exposure Diablo or Joystick head-light as it serves double duty as cache battery/power bank as well as its original use as a helmet light, should you get into some gnarly trail late at night. When looking for a cache battery/power bank its helpful to have one with "pass-through charging". This means you can charge the battery and use it to power other devices at the same time. Rob Davidson used a Plox branded one in his Tour Divide.

Some connection scenarios rendered in an "ascii diagram"

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 

( hub )  - - - -  * LIGHT *


( hub )  - -
                |
               USB-conv - - - - - { BATTERY }


( hub )  - -
                 |
               USB-conv - - - - - *] DEVICE [* - - - - - -


( hub )  - -
                 |
               USB-conv - - - - - { BATTERY } - - - - *] DEVICE [*


( hub )  - - - -  * LIGHT *
                |
               USB-conv - - - - - *] low-drain-DEVICE [*

Obviously some set-ups might let you charge or power, and use the light at the same time but its unlikely you are going to be making enough power to do both equally well, but it depends on the load. If you read Kerry at kLites info page you will learn that some devices are more power hungry than others. Cell phones vs GPS for instance. You may still be able to use your lights and power your low-drain GPS.

- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

A very good primer can be found here:
http://www.velorutioncycles.com/dynamo-systems-a-primer/

Some popular dynamo lights
I'm not sure how useful the bottom two are but the top two are very robust and proven in Bikepacking circles.
Exposure Revolution
Klite
Supernova E3 triple
B+M
Son Edelux

The best dynamo hubs seem to be the following. Some are just licensed versions of another.
Shutter Precision
SON Schmidt
Supernova
Exposure

It's my understanding that the Supernova and Exposure are licensed versions of the Shutter Precision (SP) hub. The SP hub is not user serviceable but can be overhauled for a reasonable fee after sending back to the factory. The SON hub is user serviceable, if you are keen. SP claim their system is more simple hence robust and therefore is not high maintenance. SON has been around for a long time and many people will say they have had no problems despite commuting 50kms a day through a monsoon for 5 years solid! The SON can cost twice what the SP hub costs but it is worth shopping around for prices. The Exposure Revo hub/light kits are amazing value if you can get one, as the Exposure parts, (lights) are incredibly expensive bought separately.

The best Dynamo lighting resources I have found are from Kerry at kLite, (in Australia) and the  Peter White Cycles sites (US).

Here are a few more real life cases where people are using dynamo lighting systems in Bikepacking situations.

Ollie Whalley.
Rob Davidson.
Composite MTB.
Mike Hall.

More to come as I discover it!

Read More