By Fred Matheny
Price: $160 w/o bottom bracket
Crankarm sizes: 170, 172.5, 175 mm
Weight: 600 gm
Source: bike shops, catalogs
How obtained: sample from company
RBR advertiser: no
Tested: 52 hours
Stock gearing on road bikes is insane when you stop to think about it. Nearly all bikes nowadays come with 53/39-tooth chainrings and a 12-23 or -25 cassette. We’ve come to accept this gear range, from 42 or 46 gear inches on the low end to a high of 119 inches.
But those are the same gears commonly used by the pros. What’s a recreational rider with half a cash rider’s power doing with a low gear of 39×23? For that matter, this setup isn’t suitable for domestic racers in most categories, either. But conventional cranks with a 130-mm bolt circle diameter won’t accept inner rings smaller than 39 teeth.
Thus, the popularity of triples with their usual low gear of 30 inches, produced by a 30-tooth chainring and 27-tooth cassette cog. But triples have disadvantages: cost, weight, chain rub, touchy front shifting and a wider stance (often called, erroneously, the Q factor).
That’s why double cranks with a smaller, 110-mm bolt circle make lots of sense. Washington state manufacturer Full Speed Ahead (FSA) produces these ???compact??? models and fits them with rings of 50 and 34 teeth. This is just the ticket for anyone who wants a more sensible and useable gear range.
You won’t lose any style points. American cycling hero Tyler Hamilton used an FSA crank (reportedly with a 38-tooth small ring) in the 2003 Tour de France when his broken collarbone forced him to stay in the saddle and spin on climbs.
I rode FSA’s alloy Energy Compact Crankset with 50/34-tooth chainrings for four months on my Serotta Ottrott. At $160, this is FSA’s budget crank. You can spend twice as much for the Carbon Pro Elite Compact. The extra dough saves about 80 grams and provides carbon’s gee-whiz factor.
Paired with an 11-23-tooth cassette, the mini rings gave me about the same gear range as a 12×25 cluster with conventional 53/39 rings. With a 12-27 cassette, I got a bottom gear of 34 inches. That’s equivalent to a triple crankset’s 30×24 — plenty low to get over nearly anything That’s paved.
The crankarms can be ordered to fit a Shimano Octalink or ISIS Drive axle. The main setup issues involve the front derailleur. First, it has to be lowered to accommodate the smaller rings. Then the adjustment is tricky, so unless you’re good, farm out this task to your local mechanic. Uncle Al made short work of this potential hang up for me.
The Energy Compact has hollow forged arms and a CNC???d spider. Chainrings are CNC???d, too, as well as ramped and pinned for better shifting. They’re compatible with 9- and 10-speed chains.
Shifting was smooth and precise. This crank isn’t quite as stiff as the Dura-Ace model it replaced on my bike, but the difference is minimal. I used the Energy Compact for a 400-mile week at a cycling camp and it worked flawlessly. I’ve heard stories of premature chainring wear, but after 50 hours I can’t see any.
Crankarm length is limited to 170, 172.5 and 175 mm. A greater range of sizes would allow more riders to get comfortable with this design.
I like the compact crank concept. I would keep a conventional crankset on the bike I race, but for fast group rides and hard training here in the Rockies, compact makes sense.