For which there is no easy answer. Motorcycles are comparatively easy to maintain, but many otherwise competent mechanics regard them as black magic, so it may be done and it may not be done. Bikes also tend to age faster than they rack up miles, simply because of their nature. Cages get to the 100K mark pretty fast, bikes don’t often even live that long, for reasons entirely unrelated to the wear that mileage is meant to be indicative of, to the point where 30K sounds like a million when it’s tacked onto a bike ad.
But the fact of the matter is the bikes have the same… or better… engineering than the cars that last 300000 miles, and condition and existence of maintenance records is always but always > indicated mileage, regardless of age (the exception being bikes with a known notorious failure point, like the cam chain in pre-gear-driven-cam Honda V4s). Unfortunately the only way to tell a bike’s condition is with a competent inspection, which is something you can only do from experience, and since this a site geared toward beginners that’s not quite so practical.
So with that in mind I would recommend a cutoff point of 20K for a used bike purchase without the benefit of an experienced hand and eye.
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