OK, very "it depends" question, but how fat would you say a tyre (and rim) needs to be to float over mud as opposed to sink in?
I know the old school way of dealing with mud is as narrow a tyre as possible, but I'm contemplating rocking a semi fat front on a rigid fork for mayhem (2.4" Rubber Queen on a 35mm wide rim) as opposed to dealing with a horrid narrow tyre up front on the rest of the course.
Just a thought anyway, but is a 2.4" RQ on a 35mm rim too narrow? Does it need to get to the realms of the Surly Endomorph's et al on 65mm wide rims to float over the mud properly?
got a 2.4 RQ on a 719. in greasy mud it's v. slippery. (26")
2.4 racing ralph is better. 29er though...
Even a 4" Nate on an 80mm rim doesn't "float" over mud.
Grips like shit to a blanket though. 🙂
The 2.2 RQ is pretty big so a 2.4 must be mahooosive. My 2.2 Black Chili clog with mud pretty quickly if on slower muddy sections and become fairly scary.
If it's going to be really muddy I'd be tempted by a 2.3 Black Chili Baron rather than a RQ.
No idea what they're like but another largish and slightly lighter mud option is the Panaracer Cedric Gracia Soft Conditions 2.25
trouble is, if you're floating on mud, you need paddles to get any traction on the rear, [img] http://t3.gstatic.com/images?q=tbn:ANd9GcRirV5kHu9gV3iCUPzPeIoj6V8V8-xZWUZZ6zws4f-PtuJyJ8mHtGezdoxX [/img] and you still need some pattern running the other way on the front to steer against, so long thin vanes a la Panaracer Dart, or back to a narrow tyre to cut to the bottom...
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google "swamp buggy racers" for more ideas!
Just read your OP properly (I'm not very good at that!)
The worst of the muddy bits on the MM course are the off-camber, cross slope traverses (certainly were the year I did it). You really want to be cutting in with a narrow tyre. If you're floating on a slope, you'll be in the bushes at the bottom pretty quickly.
If it's going to be really muddy I'd be tempted by a 2.3 Black Chili Baron rather than a RQ.
Purchasing by tomorrow isn't an option really... More of a case of what I've got lurking in the shed. And there happens to be a 2.4" RQ and a 35mm wide rim, a front hub, and some spokes of the right length all in my spares...
Gonna build it and try it I reckon, but more than likely revert back to a Mud X or Trailrakrr up front if the conditions really are nasty, or possibly even the Ignitor I've got. Who knows! Will see when I get there I suppose.