Wow, I've asked a question with no answer! But hear me out. I'm currently on my first overseas bike trip having just spend two months riding Sumatra, Indonesia, on a fairly trusty Honda Megapro 150. Soon I'll be in Malaysia to buy a newer and bigger bike to tour South East Asia, taking what I expect to be about eight months.
Originally my idea was to head onwards to Turkey via Iran, what an amazing trip, but I've recently begun to consider transferring to as North America and bike camping Alaska down to Mexico.
I know these are two vastly different, incomparable trips. Both would be amazing and eye opening.
From people who have done either or both, what was your experience like? Can you help me in my slow process of writing out which way to go, east or west?
The great appeal right now of the north American option is the camping and solitude, which is harder and makes less sense in Asia.
At the time I go either way I'm expecting to have about US$5000 remaining.

Consider weather in Alaska and northern Canada: Somewhere mid September it starts snowing; even without snow, nights will be cold. Still doable if you hurry, but you couldn't linger.

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Traveling The World Since: 2011
Blog: The Seductive Life (General Travel)

I don't wish to offend any North Americans here, but unless you are looking for comfort, convenience or logistical simplicity, I cannot think of any reason to choose North America over Asia.

Asia has incomparably greater appeal in terms of culture, diversity of people, races, religions, masses more history and things to see; you'll get a sense of several thousand years of civilisaiton in Asia (if you're interested) which started in different points. There are great varieties of cuisine to match, thriving, colourful bazaars and cities which have been lived in by people for several thousand years continuously.

Scenery wise, although North America is stunning (and I've not see very much of it), Asia still has the world's most impressive mountains and as much wilderness and solitude as North America. Driving around Mongolia is a true wilderness experience which certainly cannot be replicated in North America, where people still really live as part of the landscape.

SE Asia is perhaps not the place to do camping in pursuit of solitude, but you most certainly will find this in more central and western parts of Asia. Try Mongolia, the steppes of Kazakhstan, the Pamir Mountains, the endless plains and forests of Siberia (a bit buggy in summer)... I don't believe North America has more wilderness than Asia. I don't know what you mean by camping 'making less sense' in Asia, I've certainly done it plenty of times. Many of the cultures here are originally nomadic; people who have made sense of camping for millennia (though few still practice it: see Mongolia).

The only drawbacks of Asia would be the visas you need and the planning of dates and border crossings. It's more complex and expensive but you get what you pay for in my opinion.

I've been to many corners of Eurasia which could be described as being on the Silk Road, take a look at my website for some ideas.

EO

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EurasiaOverland a memoir of one quarter of a million kilometres by road through all of the Former USSR, Western and Southern Asia.

I have logged 58 countries of which 4 are in the stan's and it sure would an easy choice for me. I have done the Americas from the top of Alaska to the tip of SA and although SA is great Central America and North America are pretty bland but the Silk Road is like another world. Just my two cents. Just do it.

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Larry Davis

Believe me, I know what you are saying here. I completely understand. My hesitance stems from uncertainty of what sort of experience I want right now, and certainly that will be different when I'm ready to make the choice. The USA draws me due to the possibility of work at the end. Eight months to ponder.
I am certain that I'll get to both someday though. At least, I want to be certain.