I'm looking at a singlespeed/fixed xc bike with a 38 front and 16 rear. What does this mean for riding on mostly flat ground? Should I look at soemthing else? I don't want to be just spinning all the time. Thanks

that is way too tall. youll be spinning like crazy. im rocking 40x15 and even then, everyone is hating on how short that is

45x16 on the flats was comfy for me. I do my road fixed training on 38-16.

I am pedaling 39/16 and it's not enough in the flatlands of Fl. I am looking at getting a larger chainring.

just try to aim for the 70 GI that seems to be the most middle ground for speed/climbing. I used to ride a 48x17 and although that was a more controlled descent on steep hills I would much rather not kill my bad knee and use a much lower gearing which is now a 44x18.

werd. im rolling on 40x15 and 48x18 on my two fixed bikes. they are the same gear inches iirc

70 is great to start on

FYI There's a number of calcs available, including one for the iPhone that is great:
https://www.jpmartineau.com/iphone/bi...ar-calculator/

I'm running 47/16 and 49/17 in relatively flat terrain. There are some serious, but relatively short hills, and I don't seem to have an issue. They both work out to 75-77 gear inches. I would start on something closer to 70. At the beginning of the season, I also drop for a bit to 70ish.

I've looked at several of the calcs, although I'm not nearly cool enough for an iPhone, but don't know how they translate into the real world of riding. This is my first attempted foray into the world of one gear since my BMX days.

i live in Perth Australia which is pretty flat, currently running 51-17 which is ~81Gi
kinda highish, though suits my commute well as there are almost no stops, and is very flat.
though 1 skid patch.. however that doesn't really matter for me since skidstopping for me is impossible on 81Gi.

If you want to know how gear inches apply to real world application if you have even a cheap bike with gears just ride it in a few pre-selected gear settings you figure out using an online gear calculator.
You have to ride to figure out what a certain gear inches feels like before you go buying all kinds of cogs and chainrings.

Try this calculator, its my favorite one. https://software.bareknucklebrigade.c...it.applet.html

That's a little too easy a gear. Try a 14 cog and see how that feels. Cogs are cheaper than chainrings and a one tooth difference in a cog is the same as a four tooth difference in a chainring, IIRC.

48x17