Charging a Garmin on the bike

I’m looking for tips on the best way to charge a Garmin while on the bike. I’ve entered a long distance race so need it for navigation and it looks like Anker power banks are the STW choice but my question is how do you you charge it if its raining? Other than wrapping it in a poly bag what do you guys do?

Unless you’re planning on completely submerging your bike self amalgamating/vulcanizing tape would do the job, or insulating tape failing that. The voltages involved are so low moisture should be less of a problem than you’d think. Poly bag would be fine too I’d wager.

Have you already got a Garmin unit, if so which one? The edge 530, 830 and 1030 have an array of pins on the back which mate with a Garmin charge power pack that doubles the battery capacity. Beware, the usb ports on other units are very fragile and don’t like the vibrations of charging whilst riding. I’ve broken 2, the first was an Edge Touring, the second an Explore. Might be worth considering Dakota or Oregon models with replacable batteries.

you got a few options, easiest but least cost effective is to upgrade to a 530,830 or 1030 as above. the charging pack is an extra 100 but does have an additional USB port so you can charge your phone/light as well.

another option is to use the smart port charging function on an exposure light if you own one, a big light such as a six pack, or even toro, will run all night at decent lumens and keep your Garmin at 100%

third option is top tube bag, usb power pack, sandwich bag with a small hole in it and a rubber band. that will work fine too but you might need to tape the charging lead in place to your Garmin.

also, have you checked that you can actually have a lead plugged into your Garmin whilst its on the mount? some types actually cover the charge port flap. so a stem or even stem cap mount might be required.

Thanks folks. It’s an Edge 820.

also, have you checked that you can actually have a lead plugged into your Garmin whilst its on the mount?

Ah! Good point. I’ll go check!

Also, what capacity of power bank would I need for a 24hr stint?

How far are you planning on going? I did 240 miles in 15 hours with my 520 and the only charging it got was a quick plug into a power bank at each feed stop. I had loads of battery left when I finished too.

How far are you planning on going?

Its a 300km ride (Frontier 300) with a 30hr time limit. I’ve never done anything like this before so have no idea how long it will take me!!

I tried it once with a Garmin 810 – didn’t like it, ran the internal battery down to flat and kept switching itself off / wouldn’t take charge from an external battery on the move – fine if you stop regularly, useless if you don’t. I use an Oregon for multi-day events – also when it powers down/up, it restarts exactly where you left off.

fine if you stop regularly, useless if you don’t.

I’m going to try and stop as little as possible. Two quicks stops is my plan so far.

You can get “Angle up” and “Angle down” USB cables that basically have a right-angled connector at the appropriate end, so “Angled up mini-B”. Thus put less strain on the USB socket in the Garmin and also sit much flatter so there’s better chance of the unit fitting in the mount.

Leave the cable fitted and then just plug in the power pack when you need to. Garmins act weirdly when they’ve an external power source – the Oregon basically ignores or reverses all your power saving settings for example – they assume the external source is something like a car or motor boat with effective unlimited power.

Doubt you’d need much more than a 5000mAh powerbank – I can recharge an Oregon four times off a 10,000mAh bank, enough for four days’ riding. Look up/find out what the battery size is in your unit and also work out just how long your typical usage uses the charge.

I have got a couple of very low profile charging cables for so old Arlo lights. They work well.. might be able to get something similar.

Be careful what you have your Garmin set to. I made the mistake of leaving tracking function on my 520 Plus on on the way down to Brighton – it died at halfway.

Just had a look at the Frontier website. Unless you’re flying, you’ll have an enforced stop after 18 hours of up to 5 hours so it may be worth taking a 2,000mAh lipstick powerbank and a wall charger to boost everything up for the last 70km. Also you’re following a gpx which is more power hungry than just recording your ride, especially if you’re overlaying the route on detailled mapping. Make sure you know how to minimise the backlight to save juice as well.

I’ve managed to charge my 820 when it was in the standard out front mount, just ran a cable from a power bank housed in a Topeak top tube bag. The Topeak bag has a specific port for wire to exit so should be pretty water resistant. Disclaimer – I only did it in the dry.

As for what size powerbank, sorry I can’t be any help there as I just did it on an 2 hour ride to prove it would work when planning for a longer ride that didn’t happen in the end

I’m in for the Frontier 300 too. I just plug my Edge 810 into a 5000mAh powermonkey and it lasts ages. That’ll be what I’ll be doing for that ride too.

I’ve got a 2600 mAh powerbank which, conveniently, is exactly the same size as my Exposure Sirius front light so it just clipped into the mount in place of the light. Used it on Manchester – London and a couple of other weekend rides where there were no external charging options.

Garmins are weird with external batteries – some don’t like the vibrations, some try to turn the unit off when you unplug. Mine turns the screen backlight permanently on when it’s plugged in which slows the charging down because half the power going into it is then being used to light the bloody screen. Stupid bit of design.

With the older 800 and the 1000 I simply ran a usb cable to a battery pack while riding. I can’t get more than 10 hours out of the 1000 alone and that’s not using navigation and maps.

I’ve never damaged a usb port but I’ve had issues trying to get them to fit with different mounts. You may have to play around. I have managed to kill one by charging it in the rain.

These days I just whack a battery on at the cafe stop. 30 minutes will get me a decent boost of maybe 30%. Not enough for you but 5hours would work.

HAve a play as crazy-legs makes a good point and not all work. You’ll probably have to manually drop the brightness and turn off sensors when you plug a battery in.

Not sure what your navigation requirements are? For long rides starting from home I can know a lot of the route. So I run the garmin plugged to a battery all in a plastic bag in a top tube bag. Easy to whip out if needed.

If you are going to put a gpx file on it consider breaking it down. I don’t know how the modern units fair but 800s and 1000s can crash with longer routes and recording long rides. I’ve got double (imperial) centuries but had to break down routes and rides when I did a triple and a quadruple (/humblebrag 😉 )

I did think about getting something like this

https://www.halfords.com/cycling/bike-accessories/bike-bags-baskets/halfords-toptube-phone-bag-184686.html

so I could keep the garmin in a bag while charging and still see it.

Final thought – are you riding solo? When doing things with friends one will run the route and the other have their garmin on charge in a pocket as backup. Swap when batteries get low. If you are going solo I’d consider a backup option. My record with Garmins isn’t great – they tend to die at inconvenient times. I normally try and beg a unit off a friend.

@jonba That toptube bag looks a good idea. I might just buy a power bank and plug the phone in and use Strava as a sat nav. Given what has been said about charging Garmins on the hoof would the phone be a better option?

Given what has been said about charging Garmins on the hoof would the phone be a better option?

Well then you just end up with the same issues, especially waterproofing (phones tend to be a lot less waterproof than Garmins!) and they’ll still eat through battery and potentially all your data allowance too.

Test how much battery the Garmin uses under various conditions. Full turn-by-turn navigation plus all the connectivity like Bluetooth, power, cadence etc and you’ll be lucky to get 1% per mile. Running it as a bare “just record where I am and where I’ve been” will probably double that life, triple it if there’s a good battery saver mode – except then it won’t be telling you where to turn…

From that you can work out how much charge it’ll need and roughly when. No point charging it til it’s down to <30% battery, then it can be plugged in for an hour and repeat.

Easiest option to test it is to start a ride (on a route you know!) with a half charged unit and see how it behaves when plugged into a powerbank.

It’s been said above, but of you have the choice then an Oregon will handle ride on that length on a couple of sets of AA’s.

Don’t need data, my phone runs OS maps app in flight mode.

What about using a fenix for the navigation part? You can charge garmin watches while you record at the same time (their bike editions seem to struggle with this?).

I did the WHW in one go on summer, had my vivoactive 4 plugged into an anker power bank, finished the ride at 100% charge. Had the anker in a wee fuel tank pack at the stem.

I’ve just used a small (the size of 2x 18650 cells) to keep things topped up on multi day rides. It’s enough for an extra charge in a normal smartphone, edge 800 and small front light.

Black tac is great for this, it’s like a rubbery version of blue tac, poke the USB in, and seal around it with back tac (don’t get it in the socket). After that it won’t fall out and no way water will get in.

I’ve got a Garmin 130 and charged it on the go when I did the Cairngorm Loop in September. I used a power pack with a standard usb lead. The beauty of the 130 is that it charges in about 1 hour.

The Garmin will be fine. My 810 did the whole Tour divide with a USB cable plugged in and swapping battery packs. As mentioned above, your phone will be more faff and the big screen will chew through the batteries.

A top tube feed bag and a sandwich bag will keep the battery dry. I’d take a couple of 5k batteries so you have a back up and the ability to charge your phone if needs be.

How far are you planning on going? I did 240 miles in 15 hours with my 520 and the only charging it got was a quick plug into a power bank at each feed stop. I had loads of battery left when I finished too.

Same here. I’m a bit slower than you, taking 21 hours to do a 400km audax last year. I took a 3000mah battery which had about 50% left at the end. This was an Edge 800.

Sell the Garmin and buy a wahoo element bolt/roam. Battery life is twice as good as a Garmin.

Garmins are weird with external batteries – some don’t like the vibrations, some try to turn the unit off when you unplug. Mine turns the screen backlight permanently on when it’s plugged in which slows the charging down because half the power going into it is then being used to light the bloody screen. Stupid bit of design.

You can turn the brightness down, but every time you reconnect external power, it goes back up to max again. That’s really annoying with a dynamo.

You can turn the brightness down, but every time you reconnect external power, it goes back up to max again. That’s really annoying with a dynamo.

That’s what I meant when I said Garmin ignore all the settings when you plug in an external power source. On the Oregon it flips your screen saving settings 180deg.

@thisisnotaspoon – not come across Black Tac before, sounds interesting. I tend to leave the cable permanently plugged in then I can just attach a power bank to the other end when I need to charge it.

Oh, and, as far as rain goes – I don’t think I’ve ever worried about charging whilst it’s raining, but I reckon you’d be pretty unlucky to hit a patch of rain for the 10+ hours that an 820 would last for on it’s internal battery.

I think you already have the right device and the simplest thing to do is get a powerbank and a top tube bag with a right-angle micro USB cable to make getting the connection in easier. A 5000mAh should cover it, but might be worth plumping for a 10000 to be extra certain if it stays on 100% backlight as people have noted.

I think you already have the right device and the simplest thing to do is get a powerbank and a top tube bag with a right-angle micro USB cable to make getting the connection in easier. A 5000mAh should cover it, but might be worth plumping for a 10000 to be extra certain if it stays on 100% backlight as people have noted.

Yeah that’s what I’m thinking. I’ll get the powerbank and experiment over the coming weeks. Thanks all.

@thisisnotaspoon – not come across Black Tac before, sounds interesting. I tend to leave the cable permanently plugged in then I can just attach a power bank to the other end when I need to charge it.

It was developed by the army to stick grenades to stuff (and more morbidly, people).

Not cheap, but do get the genuine 3M stuff as the cheap stuff is rubbish. We use masses of the stuff to mount cameras/microphones as it sticks like almost nothing else and doesn’t vibrate, in a pinch you could use it and a ziptie to mount almost anything to a bike.

https://www.ebay.co.uk/p/1029587060

I charge my 810 and 520 with a USB battery pack on my 12hr TTs. Not had a problem. Pack sits in a top tube mounted bag.