12kg EVERYTHING else
A few suggestions...
1. Consider packing lighter for the everything else. I have not had my everything else not be less than 12kg for a long time. These days it has been closer to 6 kg for me. So you should be able to get down below 12kg without even getting into the weight weenie category.
2. While the 26kg limit includes the carry on you can typically take a personal item. You could carry a very small bag backpack as a personal item with a couple kg in it.
3. You might look at whether there are any items in your everything else category that you can buy when you arrive.
4. If you are close to weight, you might wear some of your heavier clothing to save that last kg or so.
OK
1. 6kg for a 3 week trip isn't particularly realistic when you are away for 3 weeks and leading a group
Clothes 1.6kg, Coat 0.5kg (A lightweight one isn't handy in Oregon rain) Fleece for colder nights 0.4kg. Toolkit, lock etc 1.6kg. Having a cafe lock (thin one( when leaving the bike in cities unsupervised is asking for trouble. Back pannier 0.6kg, handlebar bag and contents (GPS, pens, notebook etc) 1.2kg. GPS, iPad , phone and those dreaded cables add another kg. We're up to 6.9kg. (Can you get all your clothes including evening wear and still look vaguely presentable under 1.6kg?)
Now add in a spare tyre because frankly a bike shop is never close to an airport. Colombo (capital) in Sri Lanka for example has few bike shops that sell 700c tyres, yet alone finding one easily. 2 or 3 water bottles, first aid kit, wallet, guide book, need I go on?
2. Airlines are pretty strict and yes I do sneak the 1.5kg digital SLR into a smaller bag
3. Maybe the toothpaste but you really can't source the things you realistically need and it's a bit of a waste if you do as you still need to bring it home and International airports outside the US and Europe are legendary in their ability to weigh baggage to incur extra charges
4. Well I have 1.6kg of clothing, that's it (well you could add the fleece which I do wear.)
All very interesting and I have done this maybe 80 times, so if anyone can point me in the direction of a lighter bike box so that next time I visit the USA I have a spare 3 kg capacity to bring home the maple syrup I'd be really grateful.
Neil