As I got started, I had to get some cx tires put on the bike, and went to the local cross-friendly shop. They recommended Michelin Mud2's, and put them on for me. I noticed that the treads were running in opposite directions (the open part of the "v" of the tread facing the rear of the bike on the front tire, but the open part of the "v" in the tread facing front on the rear tire), but didn't think much of it, although in my head, having only an auto rain tire as a point of reference, I sort of thought the "v" should be open to the rear, to sort of direct the mud/moisture away from the tire (that actually sounds like a quote from an old Goodyear Aquatred commercial). Anyway, as I was messing around with tire pressure this morning, I realize there is actually labeling right on the tire that clearly says <--- FRONT and REAR --->, and the rear tire is facing the wrong way. I called the shop, and the owner said that they set them up that way on purpose, and that reversing the rear tire direction will help get a little better traction on dry or slightly muddy courses (which is what we're essentially dealing with here). He said that the reversed tread would get clogged a bit easier, but since we don't have that much mud, this was better for traction. He said the front was set up the proper direction, so as not to compromise control. The little research I've done, leads me to believe this might be right, as I found some articles that specifically say that "rear specific" tires can be run either direction, one being better control (but more easily clogged), and the other being better at clearing the heavier mud. But the Mud2 isn't really a "rear specific" tire, so I wondered what you guys thought about the setup.
dirtyphotons
11-16-07, 07:41 AM
i've heard this as well. makes sense to me that they'd be reversed for optimal grip.
the drivetrain is putting force on the rear wheel, meaning at the ground the rubber is pushing backward on the ground (which is in turn pushing forward on the rubber, thanks newton). on the front, it's the ground that's pushing back on the rubber, so whatever pattern yields maximum grip should be facing the other way.
the pattern which sheds the most mud seems to depend on the direction of rotation, which would be the same for both wheels.
TimJ
11-16-07, 10:37 AM
That's pretty common in general. To have 1 tire and one direction is rear, the other front. Fire xc pro mtb tires are like that, for instance. I don't know anything about that tire but that's not an uncommon thing.
M_S
11-16-07, 11:18 AM
Sheldon Brown reccomends this, though he does also express skepticism that directional tread really matters.
Ronsonic
11-17-07, 03:49 PM
Mountain bike people do that pretty much any time they've got front and rear tires that have identical tread patterns.
I don't know if it makes a big difference, but it won't hurt.
Ron
PDXJeff
11-17-07, 09:04 PM
All of the above.
M_S
11-17-07, 09:28 PM
(Thread hijak)
If you had just one mud tire for the short run, and the other was meant more for hardpack would you mount the mud tire on the front or rear? This is for riding in muddy conditions.
Also, while the mud tire is a 35 and the hardpack tire is 32, the latter actually has an ever so slightly larger profile.
pfwitucki
11-19-07, 12:37 PM
(re: thread hijack)
In general, I put the wider tire and/or the one with more knobs in the front. The reasoning? I'd rather have my rear tire skid out than the front - pretty tough to correct a front tire skid. Also, there's an efficiency benefit from a lower rolling resistance in the rear, which is more weighted. (eg - lots of folks run a mud in front and a jet in the back).
I suppose a mud might give you better traction on muddy climbs... but just run those.
M_S
11-19-07, 07:12 PM
I ran the mud tire in the rear. The size difference is really pretty negligible.
Of course, overnight the mud turned into about 10 inches of snow, so slightly different riding than I had anticipated ;).