I MAY have found the aux power plug under the left side upper front fairing. There is a thick cable running to the lights and it has an unused end with cap on it.
With a right Honda connector plug, one should be able to easily plug in to 12V aux power. I tested the plug and it is dead when power is turned off, but gives out 12 volts once the ignition is turned on. Next job is to confirm that this plug can actually safely be used and find out where I can score the proper female plug that fits.
DO NOT MAKE ANY INSTALLATIONS, MODS ETC. BASED ON THE INFORMATION ABOVE.
UPDATE
I have succesfully used the above plug as a switched power source to charge my phone & GPS.
There is also another source for switched power under the seat. Read more -> https://honda250rally.com/2017/05/10/aux-power-source-ii/
***THE SOCKET UNDER THE SEAT CAN NOT BE USED FOR POWER**
It is a diagnostics plug.
UPDATE II [Jan. 22nd.]
The connector plug seems to very hard to come by. Leave your hot tips on the comments if you have any. The connector one needs is a HX60. More info -> http://prd.sws.co.jp/components/en/detail.php?number_s=61897408
Project Honda CRF 300 L 
The Honda aux plugs on the 500x have the mating connection already there. You just need to pop out the blank seals and put in .090 pins. Perhaps the Rally is the same.
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Hi Gar, have you got a link to the pins? The Rally plug sounds exactly the same as the 500x, it just needs pins inserting.
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Sorry for the late response. Here’s the page link
http://www.cycleterminal.com/090-connectors.html
You can get the .090 pins, and grommets there, along with crimping tools. I sent a PM to the shop and got forwarded to a third party that crimped some pigtails for me, since I really didn’t want to pay for shipping a crimp tool to Thailand, when I’d get limited use out of it.
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Hi Gar,
I’m in Bangkok and would like to know where you got the crimped pigtails from. I have a CRF 250, but the Honda dealers aren’t exactly too savvy around here.
Was it just a local bike mechanic?
Thanks,
John
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I emailed cycleterminals (see post above) and asked them if they knew of someone who would make pigtails for me and overseas mail them. I explained about not wanting to purchase my own crimp tool, and ship it to Thailand, just to get six terminated pigtails made. 🙂 555 They were happy to help out. The pigtails came complete with the rubber donuts to seal up the Honda factory connector. I’d be really surprised to find even a huge Bangkok Big Wing that had the pins and grommets.
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Oh Ok, I got it now Gar, thanks. I misread your post.
I may be going that same route. You are right, even the Bigwing guys are confused about what to do; they just want to take the shortcut and wire directly to the battery.
Thanks for the reply, cheers.
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BIG Thx for this info! I will keep in mind if i need a charger for my Phone/GPS
I like your page very much. Keep on with it!!!!!!!!
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Happen to know where to buy the connection from? Site site BTW.
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I was just going to run my gps power leads directly to the battery terminal, but this aux power up front seems like a much easier place to tap in. I’m not sure which exact part(s) we would need, but I imagine this place would have them…
http://www.cycleterminal.com/index.html
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Hi guys.
I live in Bali Indonesia and basically have the same issue. The Honda teams here also are lost.
I have to assume that plug is fused? Did any of you add an additional 3 or 5 amp blade fuse to the connection?
Have you guys had any issue with it since installing?
Thanks
Ken
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If anyone needs these little connections, I have found them here…
https://global.rakuten.com/en/store/auc-hi-1000/item/2p060wpk-hx-f/?scid=wi_ich_item_rgm_link_en
I’m just about to order a slack handful 👍🏻
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Plugs have arrived in the UK and should be with me tomorrow! 5 plugs for £10 including airmail, 5 days from Japan to UK! I’d say that’s pretty good!
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I bought the CRF250 Rally Genuine ACCESSORY SOCKET , part number is 08E70-KZZ-J20, this part include all required, Accessory socket, Accessory socket stay and Harness
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Hi Darren,
Where are you based? Did you have the link for this?
Thanks.
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Is the genuine honda plug a simple plug and play or does it need some rewiring. Do you need any auto/elec skills ?
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Hi Andrew,
I ordered the socket from my local dealer.
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Found auxiliary accessory lead with connector at Motostuff
https://www.motostuff.com/honda-crf-250l-rally-auxiliary-leads.html
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Hi
Waiting for my CRF 250 Rally to arrive – hopefully tomorrow. Found this: http://motostuff.shopgate.com/item/363930
A power lead with the correct plug. Has 3 options of which nr 3 is a USB socket.
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Hi,
Ive just ordered some of these connectors from aliexpress. was 7 euro for 5 sets, ill try and post a reply here when I get them and if they fit.
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Great!
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If anyone still looking for these.
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F173876787384
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Any update–moto stuff 60 dollars posted back to uk.
I can get the plugs, but not the pins.
Honda original part not available in uk.
Anyone in uk got any further, or is cut the loom?
Thanks,
Bill
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Found these if anyone still looking
https://rover.ebay.com/rover/0/0/0?mpre=https%3A%2F%2Fwww.ebay.co.uk%2Fulk%2Fitm%2F173876787384
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I don’t think the one on ebay will work. It is female, which is the same as the one on the bike. You need a male plug to couple with the female on the bike.
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Crf has them for cheap ordered mine and can in a week I’m in Canada and crfonly ships out of California here is the link https://www.crfsonly.com/catalog/product_info.php/products_id/6829
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Hi Guys,
I’ve also found the connectors on e-Bay
https://www.ebay.com/sch/i.html?_from=R40&_trksid=p2380057.m570.l1313.TR12.TRC2.A0.H0.Xhx+6189-7408.TRS0&_nkw=hx+6189-7408&_sacat=0
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Cycle Terminal has them now
http://www.cycleterminal.com/hx-060.html
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A complete kit sold here;
http://www.easternbeaver.com/Main/Elec__Products/Connectors/Sealed/HX060/hx060.html
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https://www.auto-click.co.uk/2-way/sumitomo-2way-automotive-connectors/6189-7408?limit=100
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https://www.ebay.co.uk/itm/373253471703
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I just bought this. Will see if it works but seems like a good seller. Where do you guys mount the actual USB charger port on the bike?
https://www.ebay.co.uk/itm/233901990226
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