Crank Arm Length
So I'm getting ready to buy my PM and am going to a 50/34 crankset. I'm going with the quarq so I can kill two birds with one stone and use any wheels I choose to. But since I am getting a new crankset, I have to decide on crank arm length.
I've been using 172.5's which came stock on my Cervelo P2. I've been thinking about going to 170's.
Any thoughts would be much appreciated.
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Some of this might depend on how tall you are and how you already fit on your bike. I'm 5'2" and Todd from TTBikefit had me purchase 165's to go with my Felt B2 with the compact crank.
That's the kind of stuff I was looking for.
Coach Rich sure does have a knack for putting things in perspective. And I can't believe how familiar you are with the forums! You know where everything is!
Only if it was in EN 3.0!!!
Of course, as with everything in the triathlon world, if some is good, more is surely better no? Hence, there's been a lot of talk on various sites about people going all of the way down to 165mm's and singing the praises. I'm 6'0 and honestly would/do need to measure my inseam, I currently ride 172.5's and really can't feel much of a difference between them and my previous 175s. I'm not considering going all of the way down to 165s, but I am considering going down to 170s.
Any other slightly tall'ish EN'ers out there riding cranks as small as 170s or would I be the guinnea pig for you all? Of course, I could always just stick with 172.5s since I know they work for me, and the reason I'm having this debate is I'm going to ditch my current Quarq 53/39 and build a new compact where I have the chance to revisit all of these topics.
Hello, Am 6'6". 185 pounds. Have a Zinn custom bike with TT/triathlon setup. have 205mm cranks. Zinn's thing. Has taken over half a year to adjust but I think I finally like them. Though I wonder sometimes. I think I really like them going up hills. Robin
Trevor, I have ludicrously tight hamstrings and hip flexors, very aggressive riding position, and am seriously considering going to 165mm cranks on my tri bike so I can retain my position while straining my hip flexors less.
@Robin, those cranks are CRAZY long!! See my thoughts above re hip flexors, etc.
Generally how to set up a road bike is completely different, in many ways, than a tri bike.
Robin, those are some monster crank arms, you are quite a bit taller than me and ideal arm length is admittedly a subject that even the experts don't have definitive studies on, there's certainly no one length for everyone.
Rich, my motivations are somewhat similar. This season for me was basically throwing my the lump of clay that was my fitness onto the table and seeing if I could transform it into the facsimile of an edurance athlete. Now that I've had a taste, the wheels are in motion and I'm beginning to crunch the numbers on what it would take to get me to FOP with the pipe-dream goal to reach Kona before I roll out of 25-29 and into 30-34, I'm 25 but that only gives me 3 more race-age seasons to cut over about an hour (plus a few minutes) off my IM time.
Obviously I have too much free time post IM, but the tape measure is already out at home, spacers are coming off my bars, tests are being conducted, shorter crank arms being an idea I'm floating to go lower while still maintaining an acceptably comfortable hip angle.
Right. Lennard Zinn apparently thought the long cranks were a good idea on the custom triathlon bike he did for me. I am pretty limber in general, but I wonder sometimes about the extra knee travel.
Currently I have standard cranks with 53/39 and 11/28 on the back. If I decide to change to a standard brand crank at 180 mm (the longest available in non-custom?), should I go compact? I did pretty good on the steeper hills at Canada but may have wanted to spin a bit higher rpms at times. thanks, Robin
I went with 170's on my tri bike. Not sure how different they are than the 172.5's I had. Certainly not worse. Oh and 6' even.