Author Topic: Dynamo Wheels  (Read 2028 times)

Dynamo Wheels
« on: May 29, 2019, 03:58:11 pm »
Pretty new to Audax so sorry if this is a well-worn subject.

I want to have a go at the RRtY starting in the new audax year (1st October) and appreciate that I will need a better setup for doing some long rides in the winter months.
First thing I want to do is get a Dynamo set of lights as primary and have the ability to charge devices as well. This will be my late summer project.

What do I need to buy? I appreciate I need a dynamo hub and a light.

I am not looking for recommendations for specific pieces of kit at the moment (will come later) but just generally.

TIA

Andy

marcusjb

  • Full of bon courage.
    • Occasional wittering
Re: Dynamo Wheels
« Reply #1 on: May 29, 2019, 04:08:34 pm »
No comments on wheels - but a comment on RRTY - you can start today if you wanted.  You do not have to wait until the start of the AUK season.
Right! What's next?

Ooooh. That sounds like a daft idea.  I am in!

quixoticgeek

  • Mostly Harmless
Re: Dynamo Wheels
« Reply #2 on: May 29, 2019, 04:10:55 pm »

For me I purchased:

- Wheel with Dynamo (Shimano T8000, H+Son Archetype rim, Sapim spokes)
- Front light (Edelux ii)
- Crown mount bracket
- rear light (secula dynamo, seat stay version)
- dynamo to usb adaptor (USB-Werk)
- USB A to microUSB cable

You may want additional cable ties depending on how you run the cables. You may want a different bracket if not going for crown mount.

Not all Dynamos are equal, not all lights are equal. Don't expect to get more than 2Wh per hour of movement for charging devices.

Good luck, lets us know what you choose

J

--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Dynamo Wheels
« Reply #3 on: May 29, 2019, 04:14:35 pm »
"Out of interest, what size wheel do you have?", asked the person who wants to sell a hub-dynamo suitable for a 20" wheel...
You're only as successful as your last 1200...

Re: Dynamo Wheels
« Reply #4 on: May 29, 2019, 04:16:07 pm »
You will want

  • Dynamo hubbed wheel
  • Dynamo front light
  • A means to convert dynamo output to USB output (assuming devices to be charged are USB). This can be a combined front light with USB output or just a seperate convertor (that connects directly to the hub) that outputs USB

Mounting hardware and wiring often comes with the lights.  The mountaing hardware included is often for fitting to the top of the fork crown where rim brakes are mounted. Hubs from different manufacturers mostly require different connectors. Rear dynamo light is personal choice given how long rear battery led lights last.

quixoticgeek

  • Mostly Harmless
Re: Dynamo Wheels
« Reply #5 on: May 29, 2019, 04:18:28 pm »
No comments on wheels - but a comment on RRTY - you can start today if you wanted.  You do not have to wait until the start of the AUK season.

Agreed. Start now, and you might not have to worry about next summer.

Other advice: plan a DIY for as close to the start of each month, even if you have calendar events in the diary, this banks a ride so you dont fail when it snows on the last weekend of January and you can't ride.

I found December and January's rides the hardest this year, resulting in frost bite. Good socks and good gloves are worth their weight in gold.

Good luck!


J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Dynamo Wheels
« Reply #6 on: May 29, 2019, 04:27:59 pm »
Dynamo lights certainly have their uses but saying you *need* one to do a 200km per month is overstating it a bit!

Depending on your speed, a good many of the rides would be ridden entirely in daylight.  Even the mid-winter ones would only need a few hours of light.  And, unless you are running a mobile entertainment centre, most devices won't need recharging during a 200.

Dynamos do nibble away at your power: a very minor issue for strong riders but not insignificant for those closer to the time limits. 

Battery lights and - if you do need to recharge - a power bank would be worth considering.

bludger

  • Randonneur and bargain hunter
Re: Dynamo Wheels
« Reply #7 on: May 29, 2019, 04:36:56 pm »
to be honest yes I would love a quality dynamo setup especially for touring but it's not crucial for audax, especially if you're going to do 200s in the long dark months. I am just using battery lights right now and I am doing OK with riding in the dark on 200s and 300s. I carry a powerbank which I got from screwfix for £16 for topping up the garmin and mobile, this is more than enough for me so far and I'm not a super speed demon.
Bikepacking bargain basement: reviews of high value kit great for the tourer, bikepacker and randonneur on a budget

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FifeingEejit

  • Not Small just Far Away at the back
Re: Dynamo Wheels
« Reply #8 on: May 29, 2019, 04:40:54 pm »
Depending on your speed, a good many of the rides would be ridden entirely in daylight.  Even the mid-winter ones would only need a few hours of light.

That depends entirley on where the OP is planning to ride; starting around 8am my winter RRTY rides felt like I spent more time in the dark than daylight; I'm usually a 10 to 12 hour 200km rider.

Shortest day is 6hrs 51mins and then allow for cloud cover and precipitation and you're potentially looking at having a light on all day (as i did on a couple of occasions).
https://www.timeanddate.com/sun/uk/dundee

Edit:
My set up is partly common to 2 bikes:
SON Delux12
Secula Dynamo Rear

One bike has the EdeluxII Upside down (see post about moisture ingress)
and a USB-Werk that is connected to a PowerMonkey ExplorerII which does pass through charging

The other has an IQ-X front light

One of the rides I did on my touring bike as i didn't have the "backup" "audax" bike at that point, used up most of the time limit and the front light was a Ixon-IQ Premium Battery light, had to switch batterys over once on that as thankfully daytime was quite bright, poor positioning meant I had limited visibility from it to and from Dunning.

S2L

Re: Dynamo Wheels
« Reply #9 on: May 29, 2019, 04:51:09 pm »
No comments on wheels - but a comment on RRTY - you can start today if you wanted.  You do not have to wait until the start of the AUK season.

True, however, I think it's best to start in the winter months and get them out of the way... the most annoying thing is when you are 10 months in and the beast from the East arrives, wiping out all your efforts...  :-[
I would start in December, by the time it's April, you've got it in the bag.

caerau

  • SR x 3 - PBP fail but 1090 km - hey - not too bad
Re: Dynamo Wheels
« Reply #10 on: May 29, 2019, 04:54:00 pm »
My dynamo front light is good but not *that* good for when it's truly dark in the middle of nowhere with no external lighting.  I always supplemented it with a much more powerful rechargeable light too for night riding - switching it on when visibility was not enough with the dynamo on only.
I've never bothered with a dynamo rear light - batteries are just fine for any length of ride I've done and I carry a spare in case it bounces off into oblivion.
It's a reverse Elvis thing.

simonp

  • Omnomnomnipotent.
Re: Dynamo Wheels
« Reply #11 on: May 29, 2019, 05:00:51 pm »
Given the advancement of battery lights, I used a battery light on every Audax this year with the dynamo as the backup, the opposite of what I used to do.

Battery option probably cheaper as well.

Re: Dynamo Wheels
« Reply #12 on: May 29, 2019, 05:55:52 pm »
Dynamo lights certainly have their uses but saying you *need* one to do a 200km per month is overstating it a bit!

Depending on your speed, a good many of the rides would be ridden entirely in daylight.  Even the mid-winter ones would only need a few hours of light.  And, unless you are running a mobile entertainment centre, most devices won't need recharging during a 200.

Dynamos do nibble away at your power: a very minor issue for strong riders but not insignificant for those closer to the time limits. 

Battery lights and - if you do need to recharge - a power bank would be worth considering.
Probably better to get a Wahoo or Garmin 520 with enough run time than a dynamo to charge an iphone
   Eddington  81 miles  112 kms

quixoticgeek

  • Mostly Harmless
Re: Dynamo Wheels
« Reply #13 on: May 29, 2019, 06:06:14 pm »
No comments on wheels - but a comment on RRTY - you can start today if you wanted.  You do not have to wait until the start of the AUK season.

True, however, I think it's best to start in the winter months and get them out of the way... the most annoying thing is when you are 10 months in and the beast from the East arrives, wiping out all your efforts...  :-[
I would start in December, by the time it's April, you've got it in the bag.

Conversely, if you have 3-4 months of summer stuff done, you're more likely to stick the winter ride, rather than can it cos you can restart your streak as you've less to lose... Depends on your thought processes.

If you start now, you're 12th will be next April, among the bluebells and spring sunshine! If you start in October, your 12th is the end of summer, as autumn is starting to get ready...

Dynamo lights certainly have their uses but saying you *need* one to do a 200km per month is overstating it a bit!

Depending on your speed, a good many of the rides would be ridden entirely in daylight.  Even the mid-winter ones would only need a few hours of light.  And, unless you are running a mobile entertainment centre, most devices won't need recharging during a 200.

Dynamos do nibble away at your power: a very minor issue for strong riders but not insignificant for those closer to the time limits. 

Battery lights and - if you do need to recharge - a power bank would be worth considering.

A dynamo is about 5-6W of losses, About the same as unzipping your jacket, or having your tyres down a bit on pressure...

For that 5W, you get piece of mind, and no "Oh arse, I didn't charge the light afterall" moments.

You can get a lot of battery light and battery packs for the cost of a dynamo setup, and for audaxing, it's probably 6 of 1 and half a dozen of the other as to which is better.

Tho how the maths changes as the distance goes up, is a different question.

I've recently added a helmet mounted battery light to my setup, largely so I can point the light somewhere that isn't in the direction the handlebars are pointed.

J
--
Beer, bikes, and backpacking
http://b.42q.eu/

Re: Dynamo Wheels
« Reply #14 on: May 29, 2019, 06:25:20 pm »
Probably better to get a Wahoo or Garmin 520 with enough run time than a dynamo to charge an iphone

Just get a decent power bank. They work out as about 5g per Wh of electricity, or 10g per hour of daytime riding as per QG’s conversion rate. So for a 12 hour ride you’re getting more power out of one of these little things than you do from your dynamo.

Kim

  • Timelord
Re: Dynamo Wheels
« Reply #15 on: May 29, 2019, 06:31:05 pm »
I'm a big fan of dynamo lights, but given the state of battery technology, I reckon audax is now one of the places where they're less useful.  The key advantage of dynamo lights over battery lights is long-term reliability (particularly of battery compartment seals and mounting brackets), and not having to think about battery management.  Neither of those are a big deal for one-off rides you're planning weeks in advance, as you can work out exactly how much battery you need, and make sure your light isn't broken before you start.

Commuting and touring, absolutely.  And if you've got them, you won't regret taking them on an audax.

You still need a head torch or something (possibly a bastard-bright battery light to use as a 'main beam' for descending):
 Dynamos don't put out much power when you're fixing a puncture.
To ride the Windcheetah, first, you must embrace the cantilever...

Re: Dynamo Wheels
« Reply #16 on: May 29, 2019, 06:43:50 pm »
Commuting and touring, absolutely.

Even for touring the use case is pretty marginal. If you find yourself cycling in the dark on a summer tour, you’ve cocked up your planning somewhere.

(Or you’ve been to the pub)

Kim

  • Timelord
Re: Dynamo Wheels
« Reply #17 on: May 29, 2019, 07:39:33 pm »
Commuting and touring, absolutely.

Even for touring the use case is pretty marginal. If you find yourself cycling in the dark on a summer tour, you’ve cocked up your planning somewhere.

(Or you’ve been to the pub)

It's mostly that you have to devote zero planning to lighting.  So you can run the lights all day because it's pissing it down without impacting your ability to see where you're going on the way back from the pub later.  Not having to remove lights from the bike so they don't get nicked is handy, too.
To ride the Windcheetah, first, you must embrace the cantilever...

Socks

  • FFCT rally, France 2012
Re: Dynamo Wheels
« Reply #18 on: May 29, 2019, 07:40:05 pm »
A couple of suggestions:

- good quality rechargeable lights are increasingly cheap and reliable

- if you need backup power for gps or phone a battery pack is easier and cheaper.  For a 200k a Garmin or wahoo should be ok but still worth taking a backup just in case.  Nothing worse than doing a mandatory diy but not having the good track to prove passage.

- and ditto to the suggestion about getting the DIY done early in the month just in case (and to allow for the weather)

bludger

  • Randonneur and bargain hunter
Re: Dynamo Wheels
« Reply #19 on: May 29, 2019, 07:46:54 pm »
I think the case is much more applicable when you're doing a self supported tour (i.e. wild camping or RATN). Certainly for me that was a concern in my last tour - I'd factored having to hang out in a train station with a plug socket or something for a few hours to charge everything up before finding somewhere quiet to bivouac after dark.
Bikepacking bargain basement: reviews of high value kit great for the tourer, bikepacker and randonneur on a budget

https://yacf.co.uk/forum/index.php?topic=109048.msg2312359#msg2312359

Re: Dynamo Wheels
« Reply #20 on: May 29, 2019, 08:22:18 pm »
Commuting and touring, absolutely.

Even for touring the use case is pretty marginal. If you find yourself cycling in the dark on a summer tour, you’ve cocked up your planning somewhere.

(Or you’ve been to the pub)

Or in a tunnel.
Quote from: tiermat
that's not science, it's semantics.

FifeingEejit

  • Not Small just Far Away at the back
Re: Dynamo Wheels
« Reply #21 on: May 29, 2019, 09:00:39 pm »
Commuting and touring, absolutely.

Even for touring the use case is pretty marginal. If you find yourself cycling in the dark on a summer tour, you’ve cocked up your planning somewhere.

(Or you’ve been to the pub)

Or in a tunnel.

When I read that I remembered that day I was sitting at work, middle of summer a couple of years ago and it got so dark that the flood lighting came on in the carpark and you needed it to see... But then I realized if I was on the bike and saw that I'd shove the battery light on and find somewhere to hide ASAP.

Kim

  • Timelord
Re: Dynamo Wheels
« Reply #22 on: May 29, 2019, 10:15:56 pm »
Commuting and touring, absolutely.

Even for touring the use case is pretty marginal. If you find yourself cycling in the dark on a summer tour, you’ve cocked up your planning somewhere.

(Or you’ve been to the pub)

Or in a tunnel.

Funny thing about tunnels is that I tend to remember the bike lights before the photochromic glasses...  :facepalm:
To ride the Windcheetah, first, you must embrace the cantilever...

quixoticgeek

  • Mostly Harmless
Re: Dynamo Wheels
« Reply #23 on: May 30, 2019, 12:40:59 am »
Even for touring the use case is pretty marginal. If you find yourself cycling in the dark on a summer tour, you’ve cocked up your planning somewhere.

(Or you’ve been to the pub)

Or you're me... On my way to Hell, I had several days where I went quite late, well into dark. I was bivviing, so basically the moment I stopped, I'd be in bed trying to sleep within 15 minutes. No point wasting daylight on that, so I'd go until it was dark, then find a suitable place to stop. I know my way round my bags in the dark, so don't need the last of the day light to make camp. One night I planned to ride a bit deeper into the night because it was forecast to be totally clear, and I was hoping for good star views. But then we've established that I'm weird ;p

Others may choose to ride at night due to temperatures by day being too warm.

When it comes to battery vs dynamo, putting aside the emotional side of it, for rides where you have easy access to recharge, then the technology has moved back in favour of batteries. But that does require you to have access to charging, you also need to be careful in calculating your power budget. As an example, my budget for the TCR is looking like this:

- Wahoo Bolt (10Wh* (Needs charging 1.6 times per day))
- Tracker (11.8Wh (needs charging every 2 days (conservative estimate))
- Mobile phone (10.6Wh (Needs charging 2 times per day))
- Head light (12.6Wh)
- Camera (4.86Wh)

This gives me a total power requirement of: (10*1.6)+(11.8/2)+(10.6*2)+12.6+4.86.

60.6Wh. per day.

With 10 hours of movement per day, giving 10 * 2Wh of power from the Dynamo (5V @ 500mA == 2.5W, assuming 80% efficiency of power bank charging). Means power deficit of about 40Wh per day. My battery pack is 100Wh, so I have 2.5 days worth of power. *BUT*, I start with all devices charged, and I can charge them fully at the end of the 3rd day. Meaning for my plan of Hotel, bivvi, bivvi, repeat. Gives me just enough power. *BUT* Now we get into the question of charging the 100Wh battery pack. Charging with a typical 2.4A 5v USB socket, you're getting 12W of power. At 100% efficiency, that 100Wh battery pack would need over 8 hours to charge. You don't get 100% efficiency, so it's nearer 10 hours. I really don't want to spend 8 hours at a hotel, let alone 10, not on an event like the TCR or RatN. Fortunately my power pack has 2 inputs, so rather than putting 2.4A in, I can put in 4.8A. 24W. 100% efficiency would give a little over 4 hours. Make it nearer 5 with inefficiency etc... Much more reasonable.

*BUT* this is without any lighting in there, other than my auxiliary head light. Let's add a light. For the sake of maths, let's use a hypothetical 3W light. Let's assume 8 hours of dark cycling (on RatN I pedalled late into the night most nights, and 2 nights, the full night). So we're now adding 24Wh of power to our calculations. So now we're at 85Wh of power, per day. With no dynamo, there's no -20Wh offset. With the same 3 day usage plan, that's 255Wh. Best case that's about 1.3kg of battery packs. And you're gonna need to have a many more charging sockets when you stop. 60Wh of power, to be in with a chance of a 5 hour stop. That's 5 USB ports at 2.4A. On top of enough ports to charge all 5 actual devices. So 10 ports total.

My 4x2.4A usb charger unit is 140g. So we're adding another 140+g for chargers.

This is getting heavy...

Now, I've talked here about events like the TCR, RatN, or my road to Hell. But the original discussion pertained to 200's for RRtY. For a simple 200, assuming a start at 0800-0900, and a UK, or western European time zone. Your worst case is that you want 24Wh of lighting power, (8 hours of lighting needed), half a top up of the mobile phone, and half a top up of the wahoo. That puts us at about 33Wh. or around the 9000Mah mark. But only about 10Wh of that will need to come from a battery pack, (I'm guessing the power for the light is built into the light).

In theory the Wahoo can do the full ride on a single battery charge. But it's close, if you're using the back light, or running a full value times, so you're gonna want to plug it into a battery pack at one of the controls (or food stops on a diy), just to top it up and reduce the "oh fuck" moment when it dies 5km from the finish.

That just leaves the question of what would be a suitable battery powered light if you went that route.

But, for all of this, for all of the maths. My preference is for a dynamo light anyway. I don't have to worry about charging it, I can literally, submit the DIY application, and hit the road the next day without needing any logistical faffing about. My light is always "charged". But that's a decision made as much on an emotional level, rather than a rational one.

Ultimately, it's a bike ride, not a trip to Mars... your mileage and power usage may vary...

J

*(Actual size, I'm not sure of, as I can't find any clear data on this)

PS Oh arse, just realised I've done all that, and forgotten that I'm swapping to Di2, which means another 1.85Wh of power needed about every 3 days. Not gonna edit all my maths now tho. sorry.
--
Beer, bikes, and backpacking
http://b.42q.eu/

caerau

  • SR x 3 - PBP fail but 1090 km - hey - not too bad
Re: Dynamo Wheels
« Reply #24 on: May 30, 2019, 01:43:45 pm »
Have you considered that you may be overthinking this??  :jurek:
It's a reverse Elvis thing.