Author Topic: Simple route finding on PBP  (Read 9844 times)

Re: Simple route finding on PBP
« Reply #25 on: 04 February, 2019, 11:47:55 am »
In 2015, on the return leg I was mostly on my own and at some unearthly hour I came across a road junction in total darkness and met a bewildered American rider who was stopped there and he asked me which way we go. It appears somebody had stolen the  signs and there was 3 options in which way we could go. As I had a Sat Nav, I just told him and he tagged on behind.

The funny bit, next thing we are decending rapidly down a steepish hill with the American rider in tow behind me, and he kept praising me to be with someone who knows where they are going. All of a sudden I hit a bump, my lights went out and I was plunged into darkness. Because of the speed, I dare not let go of the bars to try and get them going until I slowed enough. I just thought to myself, I might know where I'm going, but I wish to hell I could see where I was going and could not stop laughing to myself. Oddly enough, I never saw the American again after I got to the bottom of the hill. Maybe he thought a was a lunatic and turned my lights off on purpose and decided to stay clear of me.

If I had just a map as a backup, and as I may not have been following the map as I would have been relying on the signs it would have been in my pocket or bag, the issue would have been to find on the route exactly where I was.

So the morale is, if you use a map, you need to be following it the same way as you would have a Sat Nav to confirm things.

quixoticgeek

  • Mostly Harmless
Re: Simple route finding on PBP
« Reply #26 on: 04 February, 2019, 11:52:32 am »
I'd never thought of connecting my gps to my dynamo fed E-werk to have always-on backlighting at night, only for charging or emergency power.  What a good idea.  Ample juice to run head and taillights concurrently?  (I guess now that we use LED lights with dynamos rated to power incandescent bulbs there might well be)

Depends on the device as to how much of a good idea this is.

a) If it has a built in LiPo battery, running it off the ewerk is going to keep that battery at 100%, which it's not going to like, ideally for most LiPo batteries they last longest if kept between 20% and 80% (I wish devices offered this as an option).

b) if you slow down and there isn't enough power coming into the ewerk, you can end up with it getting a few seconds/minutes of charge, then nothing, this doesn't do internal batteries any good

c) If you run with the usb connector plugged in, over time the vibration can cause the connector to fatigue and come separated from the PCB inside the device, then you can't charge at all.

You are better off, using the ewerk to charge a battery pack, and then use that to charge your GPS when you stop for controls. Most devices with built in LiPo batteries can get a good few hours worth of charge in the time it takes to eat lunch (about 30 mins).

Remember, your ewerk is going to produce about 2.5Wh of power for every hour of cycling. If you are going the power bank route, then you are going to have a full cycle efficiency of at best 80%, giving you realistically 2Wh. If you cycle for 15 hours per day, that's 30-45Wh of available power. But you only get that if you are not also running the Dynamo light.

A Garmin Edge 520 has a 600mAh 3.7V battery (P=IV P=0.6*3.7=2.2Wh). Now a 10000mAh ikea battery pack has a capacity of 37Wh. Which means if you started with it fully charged, you could charge your Garmin fully 16 times over (give or take).

I run a USB-Werk on my bike, for charging a battery pack, but since I upgraded to a 26800mAh (98Wh) pack[1], I've found that actually it's not really worth the faff if I am stay in a hotel every 3 nights or so. I did have to get a specific power bank, with dual inputs, as I found that the larger packs just didn't charge fully in the short ~6 hour sleep I get on a race. But this is then enough to charge my devices (phone 1.5x per day, wahoo 2x per day, inreach+ 0.5x per day), and still have power in reserve if I decide to have an extra night in the bivvi before a hotel visit. On the second day of having recharged the bank, I may plug it into the usb-werk, but I'm not sure it really does me much benefit. But this is all calculated based on 2 week ultra race. For a 90 hour Audax, the power bank would be enough to charge everything. Battery power density has gone up, battery price has come down, it actually makes dynamo power even for lighting a questionable proposition. 3W of power to run the light. 10h of darkness, that's 30Wh of power. My Anker is 590g. A Son 28 is 440g. The anker would power lights for 30 hours (give or take). A standard Shimano hub is about 140g. So for a 400g penalty, you can have battery power, which will save you about 5W in resistance. Tho I'm not sure how much that extra 400g would slow you on the climbing... Ultimately you pays your money and makes your choice. Just be aware the variables are changing as the technology evolves[2].

J

[1] Anker Powercore+ 26800 - (https://amzn.to/2G64YZu)
[2] The next generation of battery technology will really skew this in favour of battery over dynamo, if even half the 10x projected density improvements come about, it's just not going to be worth running a dynamo if you can get access to charge your battery every few days...
--
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frankly frankie

  • I kid you not
    • Fuchsiaphile
Re: Simple route finding on PBP
« Reply #27 on: 04 February, 2019, 12:32:53 pm »
[1] Anker Powercore+ 26800 - (https://amzn.to/2G64YZu)

You cannot seriously be advocating carting a 26Ah battery pack round PBP
when you're dead you're done, so let the good times roll

quixoticgeek

  • Mostly Harmless
Re: Simple route finding on PBP
« Reply #28 on: 04 February, 2019, 12:38:08 pm »
[1] Anker Powercore+ 26800 - (https://amzn.to/2G64YZu)

You cannot seriously be advocating carting a 26Ah battery pack round PBP

At <600g, it's not a major weight. But actually if you read what I wrote, you'll see that I suggested even a 10000mAh pack would be more than enough to keep a GPS going for the whole of a PBP.

I'm not riding PBP, but if I was, I would probably carry my 26800mAh pack with me, mostly as I already have it. I intend to take it on the TCR. A friend in a Velomobile will be carry about 1.5kg of batteries for his lights on PBP.

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

Phil W

Re: Simple route finding on PBP
« Reply #29 on: 04 February, 2019, 12:53:16 pm »
You can certainly navigate using the arrows only.  The first night (if in 90hr) there will be enough lights ahead and behind on the road that getting lost would be impressive.  The second night it is possible to find yourself in a group with no lights ahead or behind.  In 2015 on said second night I was in a group of Japanese and we ended up going slightly over 10km off route, then needing to retrace our route; so 20km off route.  We stopped (and retraced) when we came to a pitch black village and not a sound or person to be heard.  So expect outbound arrows to be missing in the odd place.  On the third night you could navigate via the bodies at the side of or on the road. If you are relaxed about the odd bit of going off route and retracing etc. then you will be fine.

frankly frankie

  • I kid you not
    • Fuchsiaphile
Re: Simple route finding on PBP
« Reply #30 on: 04 February, 2019, 01:01:34 pm »
[1] Anker Powercore+ 26800 - (https://amzn.to/2G64YZu)
You cannot seriously be advocating carting a 26Ah battery pack round PBP
At <600g, it's not a major weight. But actually if you read what I wrote, you'll see that I suggested even a 10000mAh pack would be more than enough to keep a GPS going for the whole of a PBP.

4x AA lithium primaries will power a GPS for the whole of PBP.  Weight 60g, reducing to 30g when you dispose of the first pair.
when you're dead you're done, so let the good times roll

SPB

Re: Simple route finding on PBP
« Reply #31 on: 04 February, 2019, 01:17:56 pm »
[lots of good stuff]

Good point about LiPo not liking being kept at 100%.  To avoid outages I could use my B&M cache battery but that adds weight, so I'll probably forget the idea and go back to my original plan of using my trusty etrex with lithium AAs.  That'll get me round, with a fresh pair of cells halfway if necessary.  It's only 4 days I should remember, not 4 weeks.  I'll just do my usual periodic tap of the knob to illuminate the screen at night and check I'm still en route.

Phil W

Re: Simple route finding on PBP
« Reply #32 on: 04 February, 2019, 01:22:44 pm »
[1] Anker Powercore+ 26800 - (https://amzn.to/2G64YZu)
You cannot seriously be advocating carting a 26Ah battery pack round PBP
At <600g, it's not a major weight. But actually if you read what I wrote, you'll see that I suggested even a 10000mAh pack would be more than enough to keep a GPS going for the whole of a PBP.

4x AA lithium primaries will power a GPS for the whole of PBP.  Weight 60g, reducing to 30g when you dispose of the first pair.

Indeed one pair of AA lithiums can get you through 3/4 of the way around or even back to the finish if you are a faster rider.  Four lithium AAs plenty.

Kim

  • Timelord
    • Fediverse
Re: Simple route finding on PBP
« Reply #33 on: 04 February, 2019, 01:59:07 pm »
I'd never thought of connecting my gps to my dynamo fed E-werk to have always-on backlighting at night, only for charging or emergency power.  What a good idea.  Ample juice to run head and taillights concurrently?  (I guess now that we use LED lights with dynamos rated to power incandescent bulbs there might well be)

Depends on the device as to how much of a good idea this is.

a) If it has a built in LiPo battery, running it off the ewerk is going to keep that battery at 100%, which it's not going to like, ideally for most LiPo batteries they last longest if kept between 20% and 80% (I wish devices offered this as an option).

b) if you slow down and there isn't enough power coming into the ewerk, you can end up with it getting a few seconds/minutes of charge, then nothing, this doesn't do internal batteries any good

I wouldn't worry about this sort of thing for a one-off big event that costs more than the GPS does, thobut.


Quote
c) If you run with the usb connector plugged in, over time the vibration can cause the connector to fatigue and come separated from the PCB inside the device, then you can't charge at all.

This on the other hand is tempting a failure mode that could ruin your day on the event itself.  See also: Water ingress.

On the gripping hand, Garmin Edge series remain inexplicably popular, so plenty of people do manage to use USB connections on the bike.


Alternatively, use an eTrex and budget for another set of spare AAs and you can have all the backlight you want.

quixoticgeek

  • Mostly Harmless
Re: Simple route finding on PBP
« Reply #34 on: 04 February, 2019, 03:28:50 pm »
4x AA lithium primaries will power a GPS for the whole of PBP.  Weight 60g, reducing to 30g when you dispose of the first pair.

How do I install those on my Wahoo Elemnt Bolt?


I wouldn't worry about this sort of thing for a one-off big event that costs more than the GPS does, thobut.

Yes, except you're gonna probably want to do all your SR series with much the same kit so that you are familiar with it. I'm not sure I'd consider something like a Wahoo Elemnt to be a single use item like this. I'd like to make sure that my use doesn't adversely effect it's life.
Quote
This on the other hand is tempting a failure mode that could ruin your day on the event itself.  See also: Water ingress.

On my stem I have a second Wahoo mount, this allows me to run with the power cable plugged in. This is an emergency use only solution, for use only when it's dry, and no risk of pavé, for when there's an hour left on the Audax, but the battery is at 10% and you just want to make sure to get there in one piece. I think I've used it 2-3 times since I got the Wahoo.

Quote
On the gripping hand, Garmin Edge series remain inexplicably popular, so plenty of people do manage to use USB connections on the bike.

Yes and no. For most riders, they do what I do, they take the device into the cafe, charge it while they eat/drink, then fit it back on the bike and ride off. I'd wager the majority of Garmin Edge series owners do not do rides long enough to need to recharge the device, you can tell this from the number of bugs that arise when the device is used by ultraracers. The number of nav screw ups have been down to shitty garmin's is mounting up.

Quote
Alternatively, use an eTrex and budget for another set of spare AAs and you can have all the backlight you want.

I have an etrex 10, it's not ideal, lacking a map etc... I've considered getting a 20, as a backup nav device, esp as I've now been educated that if I want to put a route into an etrex, I have to upload it as a track... tho I'm unsure how an etrex 20 will handle a track with a few 10's of thousands of points, but we did this debate elsewhere... Can you program tracks into an etrex 10 from a mobile phone? Does it support ANT+ sensors?

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

Re: Simple route finding on PBP
« Reply #35 on: 04 February, 2019, 04:30:03 pm »

I have an etrex 10, it's not ideal, lacking a map etc... I've considered getting a 20, as a backup nav device, esp as I've now been educated that if I want to put a route into an etrex, I have to upload it as a track... tho I'm unsure how an etrex 20 will handle a track with a few 10's of thousands of points, but we did this debate elsewhere... Can you program tracks into an etrex 10 from a mobile phone? Does it support ANT+ sensors?

J

My 20 is fine.  I don't normally ask it to navigate, because that becomes a bit approximate and is a faff.  So all I do is follow the [choice of colour] line.

I'd load PBP as two tracks, out & back.  Neither would need more than 3000 points, you could get away with somewhat less. 

JonB

  • Granny Ring ... Yes Please!
Re: Simple route finding on PBP
« Reply #36 on: 04 February, 2019, 04:35:12 pm »
I have an etrex 10, it's not ideal, lacking a map etc... I've considered getting a 20, as a backup nav device, esp as I've now been educated that if I want to put a route into an etrex, I have to upload it as a track... tho I'm unsure how an etrex 20 will handle a track with a few 10's of thousands of points, but we did this debate elsewhere... Can you program tracks into an etrex 10 from a mobile phone? Does it support ANT+ sensors?

  • An etrex will take a track of 10,000 points and using Basecamp or Phil W's tool you can reduce the number of points without losing navigational detail/accuracy (note - a track won't give you turn by turn, it's just a line on the map but it's very effective), what this will give you in terms of length I'm unsure but I'd guess between 400-600 km. What I tend to do is to split the track into sections and the key thing here is that switching tracks will not disrupt or break your recorded track log so it will keep on recording overall distance/climb etc
  • I'm not aware of the ability to connect a mobile phone to an extrex, it's lacking in bluetooth
  • Yes, it supports Ant+ (at least I know the 30 does, not sure about the 20)

Re: Simple route finding on PBP
« Reply #37 on: 04 February, 2019, 04:52:41 pm »
4x AA lithium primaries will power a GPS for the whole of PBP.  Weight 60g, reducing to 30g when you dispose of the first pair.

How do I install those on my Wahoo Elemnt Bolt?

Something like this: https://vetco.net/products/4-x-aa-battery-holder-usb-power-supply

I have a 2xAA battery version, I've used it plenty of times to keep my GPS going for longer than 12h.

(You need to have a GPS that will run off external power rather than going into external drive mode, a power only USB cable sometimes helps but some devices are designed to turn off when charging.)
"Yes please" said Squirrel "biscuits are our favourite things."

Re: Simple route finding on PBP
« Reply #38 on: 04 February, 2019, 05:00:51 pm »


  • An etrex will take a track of 10,000 points and using Basecamp or Phil W's tool you can reduce the number of points without losing navigational detail/accuracy (note - a track won't give you turn by turn, it's just a line on the map but it's very effective), what this will give you in terms of length I'm unsure but I'd guess between 400-600 km. What I tend to do is to split the track into sections and the key thing here is that switching tracks will not disrupt or break your recorded track log so it will keep on recording overall distance/climb etc
  • I'm not aware of the ability to connect a mobile phone to an extrex, it's lacking in bluetooth
  • Yes, it supports Ant+ (at least I know the 30 does, not sure about the 20)

3000 trackpoints is more than enough for 600.  The 20 doesn't have Ant+.

Re: Simple route finding on PBP
« Reply #39 on: 04 February, 2019, 05:03:57 pm »
Something like this: https://vetco.net/products/4-x-aa-battery-holder-usb-power-supply

I have a 2xAA battery version, I've used it plenty of times to keep my GPS going for longer than 12h.

(You need to have a GPS that will run off external power rather than going into external drive mode, a power only USB cable sometimes helps but some devices are designed to turn off when charging.)

You'd have to be careful what power regulation is in one of those - worst case scenario it feeds 6V directly to the USB port (I have one that does). Most likely it has a linear regulator (I also have one of these) which burns through the extra volt as heat and then does nothing as the battery voltage drops below 5V, which they will under load, so you're device may stop charging before the batteries are empty.

Ironically a 2xAA one would need to have a boost convertor to output 5V, so is likely to be more efficient and produce 5V from full to empty.

LMT

Re: Simple route finding on PBP
« Reply #40 on: 04 February, 2019, 05:31:13 pm »
I had my trusty Etrex 20 with me back in 2015. Certainly helped as a back up.

Kim

  • Timelord
    • Fediverse
Re: Simple route finding on PBP
« Reply #41 on: 04 February, 2019, 06:00:52 pm »
I'm not aware of the ability to connect a mobile phone to an extrex, it's lacking in bluetooth

You can mount it as a storage device on Android with a suitable OTG cable and access the GPX files.  I occasionally plot routes in Viewranger on my tablet and transfer them to my eTrex while touring.  And back up the recorded tracks.

Or remove the SD card and put it in your phone, which is even more fiddly.

iThing users are out of luck.  That's what you get for choosing an OS that pretends not to have a filesystem.


Quote
Yes, it supports Ant+ (at least I know the 30 does, not sure about the 20)

But the device support is rubbish:  AIUI it'll understand heartrate, temperature and the cadence data from a combined speed/cadence unit (but not the speed, or cadence from stand-alone cadence sensor), and that's it.  It can also use Ant+ to exchange data with other eTrexen, allegedly.

JonB

  • Granny Ring ... Yes Please!
Re: Simple route finding on PBP
« Reply #42 on: 04 February, 2019, 06:55:24 pm »
I'm not aware of the ability to connect a mobile phone to an extrex, it's lacking in bluetooth

You can mount it as a storage device on Android with a suitable OTG cable and access the GPX files.  I occasionally plot routes in Viewranger on my tablet and transfer them to my eTrex while touring.  And back up the recorded tracks.

Or remove the SD card and put it in your phone, which is even more fiddly.
Interesting, didn't realise that


Quote
Yes, it supports Ant+ (at least I know the 30 does, not sure about the 20)

But the device support is rubbish:  AIUI it'll understand heartrate, temperature and the cadence data from a combined speed/cadence unit (but not the speed, or cadence from stand-alone cadence sensor), and that's it.  It can also use Ant+ to exchange data with other eTrexen, allegedly.
Okay, I've never used it but am contemplating an HRM strap. I can vouch for the data exchange with other eTrexers ... at the previous PBP a friend's files disappeared* from view on his unit and at the pre-ride meal I was able to send him the out and back tracks which all worked well. Quite a niche function though ;)

*some kind of weird bug with the files, he wasn't the only one to experience, I think I avoided the issue by running through Basecamp and renaming

Redlight

  • Enjoying life in the slow lane
Re: Simple route finding on PBP
« Reply #43 on: 04 February, 2019, 08:26:06 pm »
I've ridden it 3 times simply following the arrows and never had any problem - and that's towards the back of the field.  I did carry a map in the saddlebag, though, just in case.

I think it also helps to have studied the route in detail beforehand so that you have a mental image of where you are at any given time. There are some quirks, such as the fact that on the return leg, before the Villaines control, you pass a turning on the left very clearly signposted to the town, but the route takes you straight on.  That's because the official route takes a longer and lumpier route in order to enter the town from the south-west (I think) whereas the other road would bring you in from the north, meaning that you'd have to navigate your own way to the control itself.


If I were to ride it again, I'd consider a GPX for night riding between Carhaix and Loudeac, as some of the turnings are small and might be missed if I wasn't wide awake, but I don't think you need it in the day time or on the relatively straightforward route between the start and Loudeac. 
Why should anybody steal a watch when they can steal a bicycle?

Re: Simple route finding on PBP
« Reply #44 on: 04 February, 2019, 10:20:00 pm »
Bit of advice if you take a kip in a field - before you doze off, make sure you leave your bike pointing in the direction you're supposed to be travelling in.

Bizzare and implausible with all the rider numbers involved, but with the addition of chronic fatigue coming into play [if you're a full valuer] it is possible to find your self riding alone at times wondering if you're still going in the right direction!
Garry Broad

SPB

Re: Simple route finding on PBP
« Reply #45 on: 04 February, 2019, 10:50:14 pm »
One of the reasons I hate "track up" on a GPS.  With north up it's obvious if I'm heading west when I should be heading east :)

quixoticgeek

  • Mostly Harmless
Re: Simple route finding on PBP
« Reply #46 on: 04 February, 2019, 10:54:36 pm »
One of the reasons I hate "track up" on a GPS.  With north up it's obvious if I'm heading west when I should be heading east :)

I just look at the little compass roundel thing that my gps puts on the screen... That plus the position of the sun... or the stars at night... I've done whole bike rides using the stars for navigation in the past... crude, but it works...

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

Phil W

Re: Simple route finding on PBP
« Reply #47 on: 04 February, 2019, 11:15:38 pm »
You can also navigate by examining the trees and plants.

Wycombewheeler

  • PBP-2019 LEL-2022
Re: Simple route finding on PBP
« Reply #48 on: 04 February, 2019, 11:15:53 pm »
One of the reasons I hate "track up" on a GPS.  With north up it's obvious if I'm heading west when I should be heading east :)

I just look at the little compass roundel thing that my gps puts on the screen... That plus the position of the sun... or the stars at night... I've done whole bike rides using the stars for navigation in the past... crude, but it works...

J
I understand that on rare occasions it is cloudy in Brittany

Eddington  127miles, 170km

Wycombewheeler

  • PBP-2019 LEL-2022
Re: Simple route finding on PBP
« Reply #49 on: 04 February, 2019, 11:17:47 pm »
You can also navigate by examining the trees and plants.
as i recall the north side of the tree will be where the lichen grows, as it is more shady. (south side in australia/new zealand etc)

Eddington  127miles, 170km