Singlespeed & Fixed Gear - Road Double Cranks For Fixed Gear

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View Full Version : Road Double Cranks For Fixed Gear


posinihilist
01-26-11, 04:35 AM
Can I put the outer 53t ring in the inner position for a 41mm chainline or do I have to use the 39t inner ring?


Higher Class
01-26-11, 06:04 AM
You can use either ring, just make sure you're using single speed chainring bolts. 53 is a little steep, though.

FKMTB07
01-26-11, 06:12 AM
Putting the 53t chainring on the inner position of a road double might give you chainstay clearance issues, depending on the frame.

But in general, the chainline of a road double (measured in between the two chainrings) is 43.5. Given a 5mm chainring spacing, this puts the inner chainring position at 41mm, which will line up with your track hubs 41mm standard chainline. Or it'll be close enough.


dookie
01-26-11, 06:56 AM
I use a Campy square taper road crank on the appropriate (111mm) Campy BB, with a Miche 1/8" ring in the outer position. I also have a 1mm spacer behind my cog. Rear hub is a Cance Creek 120mm, which I assume uses the typical chainline.

The resulting chainline is perfect, and the crankset looks a lot cleaner than with the ring on the inside.

YMMV.

posinihilist
01-27-11, 11:11 AM
Cool... thanks guys. Found a pretty good deal on some FSA carbon road cranks. I think I might do it.

amschnellsten
01-27-11, 12:23 PM
watch the carbon FSA cranks. If it is a three piece aka (spider and crank arm are separate) the spider can start to slip if used on a fg. I have the carbon track pro and I am dealing with the spider slipping on the crank arm after 300 miles.

FKMTB07
01-27-11, 12:33 PM
watch the carbon FSA cranks. If it is a three piece aka (spider and crank arm are separate) the spider can start to slip if used on a fg. I have the carbon track pro and I am dealing with the spider slipping on the crank arm after 300 miles.

If that's actually happening to your cranks, you have a bad set. It has nothing to do with their use on a fixed gear bike.

dsh
01-27-11, 01:14 PM
If that's actually happening to your cranks, you have a bad set. It has nothing to do with their use on a fixed gear bike.
Eh, while it's true that he probably has a bad set, it's not like there aren't unique things happening to the cranks on a fixed gear.

A road bike crank only ever experiences tangential force in one specific direction, and this is not reversible or subject to assembly error. It's not inconceivable that a manufacturer could design cranks to be stiffer in one direction than the other, and I'd even say it would be smart.

Whether or not FSA has done that, I doubt it. But it wouldn't be illogical if they did.

silver_ghost
01-27-11, 01:20 PM
watch the carbon FSA cranks. If it is a three piece aka (spider and crank arm are separate) the spider can start to slip if used on a fg. I have the carbon track pro and I am dealing with the spider slipping on the crank arm after 300 miles.

I've seen a number of carbon FSA cranks come apart on road and cross bikes under "normal" use. I'd stay away from them period.

posinihilist
01-28-11, 03:55 AM
I'm looking at buying the Carbon Pro Team Issue. They're the newer design where the arms and spider are not serparate. They seem to get good reviews.