scuzzo

really nice stuff.. all in prime condition and great stuff for free.. shifters, fr /rear der. crankset... the only problem is he is a smaller rider so he had 170mm and i ride 175mm.. abut the crank set is so sweet that i still think i will use them.. so... will going from 175mm to 170.. make my knees implode... or is it such a small amount i can get away with it... i rode 170mm on my very first real road bike cannondale 3.0... but it did not really bother me... or should tall dudes only ride 175mm.. ah... it was such a shock to get all this stuff free.. that i thought i would post Rob a big thinks .. so THANKS ROB!! the schwinn peleton will be rolling in style... and the Vortex will be getting some really sweet cranks.. lite too..

link0

Lots of taller riders (even professionals) prefer shorter cranks (however, the opposite is not true). You'll be perfectly fine.

rms13

I'm around 5'11 and most road bikes I've had have had 172.5mm cranks. That is mostly because the size bikes that fit me best usually come with that by default. I recently got a used bike that was fitted with 170mm and I can honestly tell zero difference. I also had a fixed gear bike for a while fitted with 165mm to avoid pedal strike. I didn't ride the fixed gear the same way I ride my road bikes but still, I never felt uncomfortable or like I was lacking any power or stamina due to the short 165mm cranks. According to Steve Hogg, we are all riding longer cranks then were common 30 years ago and 90% of us can easily have perfect fit with at least 2 different crank lengths. I read another article recently that said that most people are riding cranks that are too long based on common fitting today. But personally, just like most things on a bike I can't imagine 5 cm making a huge difference in anything

noodle soup

Going to 170mm won't harm your knees, but it might feel strange.

FWIW, it's not hard to find 7800 cranksets at great prices on eBay. I picked up a set in great condition for $56 recently.

Raiden

Also, 175mm cranksets sell for cheaper than 170s. You could probably sell your 170 and buy a 175, and come out ahead even after ebay fees and shipping.

Or put up a CL ad for a trade, insist you get an identical model, BCD etc. (or different as long as it's shimano, plus cash).

TrojanHorse

2.5mm difference is undetectable to me, not sure about 5mm. Give it a whirl and see! You can always ebay the right size and sell yours.

Bah Humbug

Going shorter can't possibly hurt your knees. It may feel weird to you, it may make you want to slightly change gearing, and you'll have to move your saddle up 5mm, but it's perfectly safe. Tri geeks go for short cranks all the time.

scuzzo

i think for now... im going to try it with those 10sp DA rings and just boots the seat up 5mm... i just got done mocking up every thing no cables done yet... but man.. that gear is nice.. and this means the Cannondale gets to ride again too... i can pass down my mix bag of ultegra 10 gear to the dale.... and have 3 sets of usable 10 speed wheels,, not sure what to do with the 9sp DA shifters and stuff but they are so thrashed they will probly go to the parts bin... any one know.. if a 9sp chainset will work with a 10 speed chain... im not sure about all the compatibility commandments as far as shimano 9sp and 10sp goes..

bruce19

I have a DA crankset I'd sell you. I have to check arm length but I'm pretty sure it's 175. If you are interested PM me. Very little use on it. I went to a compact.