I’ve seen several topics in this forum regarding crank lengths for tri bikes vs. road bikes, however I was wondering if there is a general rule that short people (me) should use shorter cranks. I am 5’1" and ride a tri bike w/ 170 (Trek WSD Speed Concept 7.8) and a road bike w/ 165 (Felt ZW3). I just had my bikes refit and the fitter pointed this out. I noticed on the forums that most run a shorter crank with their tri bike, and I can tell the hills seem a bit easier for me with the shorter crank on the road bike. I have a half iron in July so I don’t plan on making any changes to the tri bike yet, but I am thinking maybe I should switch to 165 on the tri bike. Any thoughts?
It’s not a stupid question at all. After riding with 170s for 30+ years my dear 5’2" wife switched to 155mm cranks on her extra small Speed Concept last season. She’s very happy with her improved fit and sees no drop off in power. You may need to alter your gearing a bit. My wife’s bike is set up with a Rotor 3D based P2max power meter.
I’ve seen several topics in this forum regarding crank lengths for tri bikes vs. road bikes, however I was wondering if there is a general rule that short people (me) should use shorter cranks. I am** 5’1"** and ride a tri bike w/ 170 (Trek WSD Speed Concept 7.8) and a road bike w/ 165 (Felt ZW3). I just had my bikes refit and the fitter pointed this out. I noticed on the forums that most run a shorter crank with their tri bike, and I can tell the hills seem a bit easier for me with the shorter crank on the road bike. I have a half iron in July so I don’t plan on making any changes to the tri bike yet, but I am thinking maybe I should switch to 165 on the tri bike. Any thoughts?
Go with 165 (or less) on your tri-bike. At 5’5", I switched to 165 for TT/Tri…couldn’t be happier – improved aero position, open hip angle, optimum cadence, etc. (I use 170s for road bike…)
Lots of testing has been done regarding optimal crank length vs. inseam (Zinn, etc.). The results indicate little to no correlation (some tall riders do well on 165s, some short riders prefer 175s).
The old logic used to be to use slightly longer cranks for TTs to get more torque (lots of pros raced on 170, but used 175s for TTs). The new thinking is a move to shorter cranks, since they allow you to get lower without your knees hitting your stomach.
If you feel more comfortable, no problem going to 165s on your tri bike; but it’s not like the 170s are “wrong” or “too long”.
I’d guess 155s. But, you might prefer longer.
At FISTapalooza, a few years back, Dan changed me from 172.5 to 165. The improved position and hip angle made my faster immediately. I’m 5-11 with ~34in inseam.
My girlfriend is about your height and when we bought her bike we ordered 160mm cranks from Cobb Cycling. The fitter was very pleased we’d done this, and even suggested shorter still might be worth a try.
Common consensus is that there’s no such thing as “too short” (within reason), but for shorter riders there is definitely a “too long” - that is, if your saddle height is always either too low at the top of the stroke and/or too high at the bottom, without a “sweet spot”.
I’ve seen several topics in this forum regarding crank lengths for tri bikes vs. road bikes, however I was wondering if there is a general rule that short people (me) should use shorter cranks. I am** 5’1"** and ride a tri bike w/ 170 (Trek WSD Speed Concept 7.8) and a road bike w/ 165 (Felt ZW3). I just had my bikes refit and the fitter pointed this out. I noticed on the forums that most run a shorter crank with their tri bike, and I can tell the hills seem a bit easier for me with the shorter crank on the road bike. I have a half iron in July so I don’t plan on making any changes to the tri bike yet, but I am thinking maybe I should switch to 165 on the tri bike. Any thoughts?
Go with 165 (or less) on your tri-bike. At 5’5", I switched to 165 for TT/Tri…couldn’t be happier – improved aero position, open hip angle, optimum cadence, etc. (I use 170s for road bike…)
+1. I went to 165 from 175 and I’m 5’6. Hip feels much better on the TT bike on the shorter crank. I still ride 175mm on my road bike without any problems although if I had to buy another crank I’d prob go shorter on that too. Worth the money in my opinion and it’s a quick adaption process so I wouldn’t rule out swapping now if you can do it quick and get some long rides in.
I am about your height. Slowman, John Cobb, and the entire gang at the FIST down deep clinic replaced my 165s with 145s. One advantage of short cranks for “petite” riders is that they help offset the current tendency toward high-stack bikes, which suck if you are short and flexible and like to ride steep.