Hi all...hope all is well. I guess my education continues on cycling. I am about 5ft 11"...ride a flat bar road bike 19" frame or a 56cm frame. What is the typical crank sizing? I just learned that most sizes a 172.5, 175, and another smaller size like 168.

I am asking this because...I am looking to up grade my bike...I am about ready to buy a crankset that is a 175...my local bike shop says that crank size is to large for me.? But after reading and looking at some sizing charts on bicycle cranks...een found a calucator or two..so I was able to convert it to inches...it seems that I have been running a 175 size for sometime now without and problems.

Any suggestions for info or experiences with cranks being to long or to short?

Thanks for your time.

At 5'11", you can probably use any of the standard sizes: 175, 172.5, or 170 mm.

You might stop a bit and figure out if you tend more toward the "spinner" or "masher" end of the spectrum. If you're a masher, the 175 gives you an extra quarter inch of leverage. A spinner, you save that quarter inch to get extra leg speed. Not sure, split the difference, 1/8" toward each.

If you're obsessing over that 1/8", either you're OCD or know enough to make the decision without our inputs...

I have a cycling inseam of 34 Inches and prefer a 175 mm crank arms.

https://veloweb.ca/bike-fit/

I recently talked to a fellow whose son and a friend are serious racers. Last winter they overhauled and reassembled their bikes together and in July they did it again. During the July maintenance session they discovered they had both been using mismatched crankarms for 6 months. Unless you're at the one of the leg length extremes, it probably won't make as much difference as you're thinking.

thanks for the replies guys. I guess I could be a little OCD.....just wanted to know what others thought. And since I am still kinda of new to cycling....and my education continues...asking for people opinions never hurts. Aprreciate everyone time.

Thanks