So after much research and inner reflection, meditation, intuitive hunches, signs from above etc. I decided that it's only logical that a taller rider would best fit a longer length crank which would be relatively proportional to their leg length. Any other argument against it wasn't logical to me.
Saying that a tall rider should ride a 175mm or even 180mm length crank that in reality isn't long enough, is like saying that a 5' 9" tall rider with a 30" inseam that normally rides a 172mm or 175mm cranks comfortably should instead ride a 150mm length crank, to get the most power out of their riding and a better more ideal fit.
For the record I'm 6' 2" with about a 34.5" inseam, and my weight is usually anywhere from 190-230lbs. I'm not your typical sized rider, have been riding off an on for 20 years, road, MTB, touring etc.
So I purchased a custom length crank at 190mm, according to some calculations by long crank length proponents I could have even fit a 195mm, but I was concerned about chainstay, BB height, and toe/front tire clearance and thought better to lean on the short side with with my off the shelf commercial frame, in the future I might get a custom frame built to fit a 195-200mm crank, but we'll see.
So here are my positive observations so far after riding the last two days on them. The only negative then I can think of is that my legs muscles and nerves have to get accustomed to turning a larger circle that I should have been turning all along. And that I'm so happy with my new cranks that I have buy another set for my MTB bike! hahaa
1. The cranks are heavy, but I don't mind because relative to my size 200+lbs it doesn't matter, the stiffness is more important I think, and these cranks are as stiff as they come.
2. I really like the 190mm I think this was a successful experiment
3. I put a set of FSA 50/34 chain rings on, ramped and pinned, they work great
8. I have no problem with rear chainstay or rear derailleur clearance.
9. No problems with front tire clearance
10. No problems with corning clearance that I've noticed yet.
11. I had to drop my seat about 15mm, which makes the whole bike feel different as my center of gravity is lower, but this actually feels good I think, I didn't like that I was so high in the air pushing little cranks not using my legs all the way. So between my new lower center of gravity, and my wider foot stance in both directions I feel more stable and more part of the bike like a shorter rider does getting on a typical sized bike with typical length cranks I bet.
12. I can feel that my leg muscles and nerves will need a couple weeks to become fully adjusted to the new crank length, but already from riding 1 hour I can see I have much better pedal stroke, much better power, and I'm actually able to spin better with more power and and higher RPM. I have no problem riding 90-100+RPM with 190mm cranks, in fact it feels much more natural and I'm using my full leg muscle and full potential. I already am seeing 1-3MPH AVG speed increase with similar effort.
13. I can accelerate easier now
14. When I get out of the pedals and accelerate or power over short hills I feel like my bike is responding much better and I'm not wasting energy trying to build speed.
15. There is less pressure on my knees, even when I pedal at a harder slower RPM, I often have slight knee soreness after hard rides through the hills as I have to apply so much more force with 175mm cranks.
16. My feet would often will get hot spots, my feet feel better as the pressure is less now.
17. I can spin better actually with the longer cranks, even though everyone says short cranks are better for spinning, I feel like an airplane propeller with my 190mm cranks I love them! I can not only just spin, but more importantly spin with real POWER.
18. I can accelerate and sprint faster, I can convert more of my leg strength into power because spinning is feels much better to me know with the longer cranks.
19. My pedal stroke and form is much improved from the longer crank
20. I can use my hip flexor i.e pulling muscles on the upstroke when pedaling much more effectively now as I have now 1" more total length to pull up on my pedal stroke
21. I can maintain my momentum over small hills much better, it's like I have another gear now I didn't have before. I don't slow down like I did before when hitting inclines. Before if I hit even small hills my speed would drop dramatically, my spinning had no power behind it, all I could do is crank really hard in a low RPM and sit back on the saddle to keep my speed up.
22. I'm actually thinking I could handle and might like even longer cranks 195-200mm perhaps
23. I'll probably get a pair of these cranks for my MTB also in the triple crank format
24. I much prefer the classic square tapper BB Vs the new external BB designs, the BB is much smoother and stronger then the new external BB. Every other ride I would have to tighten the crank arms on the external BB. And I don't like the exposed tiny little bearings that external BB's use, I think that external BB are a gimick. What they need to do is take the best of both and combine them, if that's possible.
- Internet rumors on forums and even "professional" blogs etc. of knee pain and flexibility issues etc. I've found at least for me to be totally incorrect as I suspected.
- I did drop my seat down as I expected I would have to do, but I also think I'm going to need to slide my seat forward slighting, and I'm pretty sure I need to drop my bars down by taking out some spacers etc.
25. Overall I will stay this experiment is a great success, I will know for sure in a few weeks of riding and my body adjusting and getting the full power out of the new longer cranks. But just from riding the last couple days I can say that I already notice a very big improvement to my riding, nothing like getting free power and speed, comfort etc. out of thin air! And as I get leaner and in better shape I will be able to tap even more power out of my body with these cranks.