Help me choose new cranks please

Triathlon Forum
1

My only bike upgrade this year will be a new set of cranks. At present I’m riding D/A 9 speed, 2002 vintage. They’re in bad need of at least a cosmetic fix, and rather than simply replace them with the same, I’d like to take advantage of the opportunity to buy something lighter and perhaps more in line with the trend of compact cranks.

I’m 5’5" 132 pounds and can’t turn the cranks hard enough to worry about me breaking something. Currently I am riding a 38/50 combination and really like it. On standard, 140mm bolt pattern cranks like those I have now, I can’t readily find chainrings below 38 teeth and wouldn’t mind experimenting with smaller if I could fit them - thus the curiosity about compact cranks. I have never used anything other than 170mm length cranks.

I am not opposed to carbon as most of my bike is carbon anyway, but I am opposed to spending ZIPP carbon crank money. My bike is a 2002 Calfee Tetra Custom with 650 wheels.

Your help/input appreciated in advance. Thanks.

2

Are you sure it’s 38?

IMO, it depends upon your set-up and how much life is left in the bike. My first thought is to buy a new cassette (12-27 - Ultegra)…I’m assuming you’re on 9-speed. Your crank is REALLY nice…although might not look sexy.

2nd thought is that be careful of saying “carbon cranks” because most of the mid-range carbon cranks are really just carbon wrapped aluminum and heavier than their alum counterpart (FSA, for example).

An external BB (FSA MegaEXO, Shimano…I future Campy) is nice for several reason, but not completely convinced it’s the BB that makes it stiffer, rather the 2 piece crank.

That said…if you need a recommendation to buy something, I like the FSA Gossamer on my CX bike (weight and value). Although, I’m going back to DA 7800 cranks for next year.

3

http://fairwheelbikes.com/shop/index.php?main_page=index&cPath=9_42
KCNC makes some good cranks, 515 grams, Isis.

4

Thanks for the reply. Of course I’m sure its a 38, why do you ask? Yes, D/A 9 spd.

I’m very very very picky about how my bike looks from a maintenance and appearance standpoint - and the cranks look worn and old compared to the rest of my equipment. There is nothing short of having them repolished professionally that I can do to improve them - which to have properly done will cost 1/2 of a new crank set. I’m looking for a potential weight savings and perhaps a greater range of front chainring selection.

I do not want to move from my 11-25 rear.

5

If you are already on a 50/38, then a compact with a 50/34 or 50/36 will only help your low end.

On my road bike, I had an FSA Carbon Pro Elite. Very nice looking, but I wasnt pleased with the shifting or the smoothness of the $100 Platinum Pro BB. A very light setup at 540g + 200g (claimed). I have taken this setup off and am currently running my standard DA7700 cranks. I have a Shimano R700 crankset with DA BB that I will put on it some time next year to try out.

The only reason I go compact is that I ride in the mountains allot and do 10000 ft climbing centuries and stuff on it. With the compact, I can run a 11/23 cassette 90% of the time and easily put on a 12/27 for the epic rides.

For the tri bike, I use DA7700 cranks with a 11/23 and 650c wheels. With the larger cogs of a standard crank and cassette combo, you get less frictional loss (actually is a very measureable difference - read it yesterday, as quantified by some grad students). Therefore, you really are better off sticking with the current setup and going larger in the cassette (maybe even back to a 53/39). If you go this route, you can ebay used DA9 cranks for well under $100 in near mint condition.

For what it is worth, I think that the DA9 cranks are the best looking crankset Shimano ever made. The one thing I hate about the thought of the new R700s I will be throwing on is the sight of those damn sawblades.

Edit: I found the link to the loss article. Somewhat interesting.

http://www.jhu.edu/news_info/news/home99/aug99/bike.html

Oh, and the other thing to consider is setting up your gearing, so that your commonly used gears (i.e. normal flat speed) is set up with a good, straight chainline.

Fact of the matter is, 100g of drivetrain weight does not matter even when climbing, but friction losses do, IMO. Although this statement is sure to start some controversy.

6

38 is the smallest you can put on a 130BCD crank. To go smaller, compact is the way to go. I’ve had a lot of success, and really like the look, of my Ritchey WCS compacts. I’m running 50/34 and I’m toying with changing the large to a 48. They are light, super stiff, and will work with your octalink bottom bracket. The cheapest place I’ve seen them is www.aebike.com. If you like the polished look, you could certainly buy the Shimano compacts that are now available.

7

You can also check out the new Rotor Agilis which will be here in January
.

8

I’m not a fan of FSA after experiencing an FSA SRM that kept falling off, even when secured with Loctite. What about the Shimano compact? Reputable manufacturer, not too heavy, good parts availability. A square taper Campy compact such as the 2006 Centaur would also work well, particularly with a nice Phil Wood bottom bracket (ti if you care about weight). However, even though I love Campy, I don’t mix S and C parts on one bike myself.

You say you can’t turn the cranks hard enough to worry about breaking things which implies you really don’t need external bearings. That gives you lots of choices, although the various manufacturers seem to be deleting all the square taper and Octalink products from their lists as fast as they can. Also be wary of ISIS, since many ISIS bottom brackets don’t seem to last very long.

If cost is no object, the weight weenies are really into THM Claviculas.

9

i have FSA ones and love them, 172.5.

for what its worth

10

I’d go with the Ritchey compact cranks…light and good looking. Add a set of compact Q Rings and you’ll be ready to rock.

11

Thanks everybody!