That's my approach too

Never a truer word spoken... I was guilty of this.

I'd say pack all the kit you intend to take on your bike, you'll have an idea whether or not it's too much by the time you've done. If not push it over and pick it up, on your own, whilst fully loaded. If you didn't have a stroke picking it up, rinse the sweat off and repeat until you do. You don't really have to push your bike over, you get the idea... you'll probably be dropping it a lot if you're riding off road, so lighten the load now and save yourself the hernia surgery or having to unpack the bike just to put it the right way up.

Some people over pack by taking nonsense items, others pack versions of kit that are inappropriate for bikes like tents that are too big, or tools they don't need. You're a hiker so you probably already have the smaller packing gear. Just replace wear & tear parts or items likely to fail before you leave. For example, you probably won't need a new chain and sprockets mid trip if you put on a good fresh chain before departure and look after them along the way - likewise bearings and brake pads etc. You're more likely to need to repair a puncture or replace a tube, bulb or fuse than strip and rebuild the engine. If you really think you need certain items send them forward to a contact along the way: join a community here on the HU forum.

Be open to things going a bit tits up, that's usually when the interesting things happen and when the trip becomes an adventure. You can't prepare for every eventuality so don't. Don't worry, 60L and your experience sounds like you're on the 'right' path. Leave yourself some room for a couple of luxury items, you have a bit more room on a bike than in a back pack.

Bon voyage comrade.

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www.AdventureVagabond.com Mongolia & Siberia 2012: Adventure Moto Madness