The Firex SL is completely redesigned for 2003 and features plenty of improvements. The crankarms are bigger, stronger, and 10 grams lighter than the 2002 Firex SL crankset. The Firex SL is forged from Truvativ's AL-66 alloy, which is 35% stronger than AL-6061-T6, the aluminum alloy most of Truvativ's competitors use in their crankarms. Available with the super-stiff ISIS Drive or standard square-taper interfaces. We've added new chamfering and disengagement features to all our rings for easier, chainsuck-free downshifting and improved upshifting. For cross-country use. Blast Black or satin silver anodized finish.
from po to the co
Date Reviewed: September 1, 2008
Strengths: very light, stiff with the isis drive, extremely durable for cross country cranks
Weaknesses: none at all
basically I've had them for 5 years,average weight around 170, plenty of drops to flat back in the day, some around 6 feet, north shore trails,alot of dirtjumping, skatepark, and street, I don't even understand how they lasted through all that, finally bent them to hell a few months back launching this natural rock lip gapping over to a large rock that is possible to wallride, havent nailed it yet though, I'm never going to forget these cranks there strong
a Cross Country Rider
from El Paso, Texas USA
Date Reviewed: September 26, 2007
Strengths: Solid, light, silent, smooth shifts... and durable.
Weaknesses: When you land on the big ring and bend the teeth, it will cause some chainsuck, until you straiten the teeth again.
I have beaten the hell out of these cranks: two to three foot drops, pole-vaulting over giant rocks, 30-40 mph downhills (and I weigh over 200 pounds). I destroyed a set of Shimano M520 MTB SPD pedals attached to these cranks and replaced them with some M970's. I broke the mounting hardware off the Fox Shock, bent a set of Bontrager rims, wore-out or broke many chains (XT's) and finally broke the Kokopelli frame on which this crankset came. Then I had the four-year-old crankset put on a new ASR-sl frame. The cranks are battered, gouged, scratched, pitted and ankel-rub worn. The big ring gear looks like it's been dragged behind a car and is missing teeth, yet it still works fine when I'm flying down the mountain at "fool" speed. And, I don't have any problems with phantom shifts nor do I have problems downshifting while under power going uphill. The ISIS drive still feels tight and I'm on the original set of bearings.
Bottom line: this crankset looks like it's been through combat and I still have no complaints. I plan to compete in the Chupacabras 100 KM MTB race in the mountians of the Chiuauan desert in Mexico next month. Yeah, if you do all mountain, extreme XC, freeride or some nasty downhill... I recommend you buy this crank, it's tough. Have it professionally installed and avoid the "idiot factor;" you're gonna love Truvativ Firex!
Bike Setup: Yeti ASR-sl, Manitou Black Super, Fox Float, Juicy Five, LX front derailer, XTR rear, Mavic CrossMax.
a Cross Country Rider
from Ottawa, Ontario, Canada!
Date Reviewed: July 16, 2004
Strengths: Price is reasonably low. Shifting is decent. Cranks seem fairly light.
Weaknesses: Crankarm isn't very sturdy landing 3' drops to flat with 150 lb rider. Chainrings flex a bit, though it doesn't create much grinding through the front derailleur.
I bent my non-drive side crankarm off a 2-1/2' drop to flat. Since then, I hear a creaking at either the ISIS interface or the pedal - I'm not sure. This crankset is not meant for urban assault or freeride. It's OK for XC and if you ride light then this seems like a reasonable crankset. It works but it doesn't push the envelope for value or durability . . . and it let me down. Hence the mediocre rating. Just like its performance. My old Shimano STX RC square taper crankset was a lot cheaper and it's never given me grief - flexy maybe but no grief. By comparaison, this Truvativ crankset hasn't been all that great.
Similar Products Used: Shimano STX RC square taper cranks, other generic crap.
Bike Setup: Santa Cruz Heckler, 5th element coil, Vanilla 125R
Date Reviewed: December 24, 2003
Strengths: Pretty light, real strong,a good all around crank for anything north shore,urban,downhill,all mountain,xc.Its a good price you get alot for your money.The isis bb is good and hardly ever creaks.
Weaknesses: The name id rather have raceface but its a good crank.Im not sure hw strong it is cus i havent done drops over 6 feet.
This is good value a good crank buy it for w\e you do.
This is my first ISIS drive crank, bought in conjunction with a Truvativ Gigapipe bottom bracket. Tech support was good both before and after the purchase. Both went on easily and have performed very well to date. I installed both myself with minimal difficulty and excellent results.(This was the first time I have ever replaced either component.) To date, I have had neither squeaks nor undue flex. Overall I feel that this BB/Crank combination is an excellent combination of value and performance.