carbon fork or steel?

[tmurdock]

I'm building up a 29er for ultra light touring.  I wondered folks opinions about carbon forks vs steel for this type of use.  Thanks. 

[DaveB]

By a "29'er" I presume you mean a MTB frame.  If so, can you even get a carbon fork with the correct geometry and clearance for the wider tires the frame implies?  Perhaps a carbon cyclocross fork would do it but a carbon road fork will have too tight clearances.

[tmurdock]

Yes, I am thinking of a mtn bike or a cross like the Fargo.  I'd like something for touring anywhere, dirt roads and light single track. 

[DaveB]

OK, assuming you can get a carbon fork with the right geometry and clearances, now the question is what's it's advantage, right?    A carbon fork will be somewhat lighter but that's it's major difference compared to steel.  The downside is, of course, cost.

You will hear that carbon reduces ride harshness and is more comfortable.  That's a bit misleading. I've ridden numerous carbon and steel road forks and see very little comfort difference.  For a road bike the weight difference is huge and that's the real improvement.  If you want a comfortable ride, use larger tires at lower pressure.

Steel will be more forgiving of abuse and for a tourer, particularly one used for even mild off-road riding, that is an advantage.