I think your needs would be well served by something like what @noahdjango described as a ‘rocksteady, no-BS mtb’ among his craigslist suggestions:
That is: any decent-quality, decently-maintained late 80s/early 90s rigid mountain bike in a size that fits you well.
- Should be cheap and easy enough to find.
- Even a good one should look like a cheap old thing to a casual thief compared to anything new, if not exactly a beat-up piece of shit.
- Strong steel frame and low-maintenance components so you don’t have to baby it too much or worry if it takes a few knocks.
- Not-too-racy, not-too-laid-back geometry that should work fine for moderate speeds on pavement and a bit of non-extreme off-road fun.
- Useful range of gearing so you can go kind of fast and get up some tough hills even if your fitness level isn’t quite avid-cyclist level yet.
- Broken? Stolen? Lost? Find out you actually hate the thing and want to ditch it for a faster road bike or a high-tech modern MTB? Well, it was cheap to try.
- Finally, it’s a damn versatile platform for experimentation. Find out you don’t really use it off-road? Just put on the fattest slick tires you can fit, some fenders, lights and maybe racks for a bombproof commuter. Or try some wackier stuff if you’re so inclined, what’s to lose? The generic Taiwanese MTB I got as my first grown-up bike in 1992 is currently a 700c/40mm slicks fixed-gear multistrada mad max frankenbike alternating between drop bars and short risers depending on the mood. I’ve learned a lot about practical bike mechanics and effects of amateur geometry changes in the process, and it’s been a lot of fun. Not a bad beater to lock up around town, either.
