callmeAL

I had to go to my local bike shop to get adjusted recently. the tech said due to my long femurs i could go from a 172.5 crank arm to a 175. this would enable me to lower the saddle and give me better reach to the bars (b/c i have a shorter torso). i have a caad9 with a fsa gossamer. i figured if i get a new crank i should upgrade to either sram force, red or slk light. also i have a compact crank and he suggested going to a regular size. my dilemma is that i have been considered upgrading my wheelset from mavic aksium to psimet, williams or soul. right now i can't do both and need to choose. i am leaning towards a new crank due to the fact it will result in a better position on the bike. thoughts?

Palomar01

It sounds like they are trying to talk you into buying a new Crank for no good reason.

If you want to shorten your reach to the bars, replace your stem with a shorter one for less than $50!

Unless of course you want the bling of the new crank then go for it. I just think your LBS tech is feeding you a line of crap.

topflightpro

Do you have any friends that could loan you a 175 crank to try out first?

Crank length is a bit subjective and preference plays a huge role in it.

callmeAL

he wasn't trying to sell me anything, just making a suggestion b/c i would buy on ebay anyway. didn't know if the crank would make more of a difference than the wheelset. unfortunately i do not know anyone with a 175.

RedC

Crank won't make more difference than the wheelset. 2.5mm is not much difference

Squirrelli

Before you make your decision, do you feel like your fit is wrong and you're too stretched out? As others have said, 2.5mm is not great but fit wise, 2.5mm can make a difference. Maybe try a bike with 175mm cranks at the shop before you make the decision.

rm -rf

Yeah, the cranks are 1/10 of an inch longer! So you could drop your seat 1/10 inch, and maybe gain 1 mm or 1/32 inch on your reach.

Do you rarely ride hills? A standard crank is good for flat lands, or faster riders.

It does sound like they are just pushing sales, odd if you are going to ebay anyway.

If you are too stretched out, try out some shorter stems and/or ones with a bigger angle, or compact bars.
I like my compact drop FSA Omega bars (only $40). The reach on the bars is short, and the drops are amazingly comfortable for me. I even changed my stem back from 90mm to 100mm after getting these bars.

seejohnbike

as others have said, your reach to the bars should be dictated by stem height/length. your saddle height/placement should be dictated by leg/femur length. they are mutually exclusive, and you shouldn't have to be moving saddle position around to get better/worse reach. (furthermore, although your saddle will be 2.5 mm lower, you're not going to move 2.5 mm closer to the bars, more like a half a mm. (if my back of the envelope calculations are correct. but possibly not, I did them fast, and it's not my job to do them for ya...)

the bikeshop tech sounds like he either A) doesn't know what he's talking about, or B) just trying to make a sale (hoping that you'll buy from him, over ebay, perhaps?)

with respect to cranks or wheels, buy the wheels. The difference in crank is going to make a VERY minute difference, with respect to both weight savings, and your positioning on the bike. A nice wheelset is an easy way to drop lots of weight, get better aerodynamics, or both.

edit: oh yeah, and compact vs regular: do you race, and are you picky/finnicky about gear choices? If you race, having standard gearing (and subsequent 'correct' choice of cassette) will give you closer spacing of gearing, and better ability to stay spot on your optimal cadence. However, if you're not super picky about the most optimal cadence, then it's nothing worth changing, as you probably have the same range of gearing as a standard, if not a little more at the top and bottom ends.

Val23708

2.5mm = 5mm difference from bottom to top = the difference between my kneeing my chest while in the drops or not.

M_FactorX19

this. seriously thats a very small change.

callmeAL

thanks for the advice. FYI my position does not feel stretched out. after that adjustment it is much better. since it seems like the crank won't make a big difference i will most likely go with the wheels. as far as racing goes, i use my bike it tri/du but not in crits. however i would like to get to the point where i could compete in those. i guess i can search the site for info on soul/psimet/williams wheels. they seem to be the preferred choice for aluminum on a $500 budget.

hueyhoolihan

the other day, i was on the track forum, and there was a good thread on crank arm length. much info, and very little mention of rider physique as a factor, the jist of the post centered on leverage or lack thereof. and various uses for both. road, sprint, track, cross country etc. seemed authoritative...