Hi everyone,

My husband and I are in the process of converting my old 21-speed Trek mountain bike into my dream commuter bike. We were going to make it into a 7-speed, because I rarely use my full range of gears, it would be lighter, and I could add a chain guard, which I've always wanted. However, it looks like most 7-speed bikes have internal hubs because the chain can slip off of the crankset when switching into low gear. I think that the chainguard could help prevent this, and we also found a cheap chain guide with excellent reviews. But I'm wondering if it's worth it. We had a bit of trouble finding a single-speed crankset that fit a 3/32" chain, so it appears that this is not too common. Most 7-speed bikes have internal hubs, but we were going to avoid that because of the lower gear ratio, higher expense, and the fact that we're not as familiar with them. I was curious what other bike enthusiasts might think. Should I just go with 21 gears? Go with an internal hub? Or will I be okay with a chainguard and/or chain guide?

Thanks for your input! Happy biking!

-K