We were having one of these either/or discussions in the shop regarding using road tires on dirt for an upcoming Gran Fondo. I was of the camp that unless the dirt is super loose and rocky that tread or lack thereof really did not make much difference and would roll better on the paved parts of the route. The other camp was you needed some tread and the more the better to handle the dirt.
We really did not get very far in the discussion before we lost interest and moved on to other topics. I had forgotten the discussion until riding out on the Palouse this morning and remembered that there was about a 5 mile section of dirt on Jackson Road that runs between Hwy 27 and Valley Chapel Road.
As I approached Freeman I thought it was time to put my money where my mouth is and ride that 5 mile dirt section on my "skinny" tires with no tread The road is paved in Freeman and for about a mile thereafter.
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| Junction of Hwy 27 and Jackson Rd at Freeman |
The road appears to have been graded recently, so there was probably more rock on the surface than you might normally encounter, but no washboards whatsoever. It still had some moisture from the rain and snow this week so dust was not an issue.
After a couple of miles of rolling along the Palouse you start descending toward Latah Creek and into some trees. Top speed was around 29 mph and the tires seemed perfectly at home on the dirt at that speed - braking and cornering were not an issue.
After the descent the road follows Latah Creek for awhile and starts the climb back up to Valley Chapel.
Climb-out was pretty non-eventful and traction good both sitting and standing back up to the paved road. I was very happy to be running 700 x 23 tires back on the road and found them quite well mannered on the dirt portion of the ride. I would consider running more volume like a 25 or 28 if riding a route that had a lot of dirt, just to be able to run a little lower tire pressure and get a more compliant and less hoppy ride.
Bottom Line:
Traction on dirt with semi slick or slick road tires will most likely not be an issue unless it is deep, loose or muddy - then, no amount of road-type tread pattern is going to be any help - so I say tire tread is not critical and riding road tires on reasonably compact dirt and rock should be fine otherwise.
Finally, I say Sammy Hagar. He had a much broader vocal range and was far less obnoxious and had a long and varied career - can anyone say Montrose?
I agree with your bottom line. The dirt on the Palouse right now, though, is as good as it will be all year. It feels nearly paved in many sections.
ReplyDeleteI rode the Ephrata Fondo last year on 700x28s (Grand Bois Cerf) and that worked well for me; as you note, you give up a bit on soft stuff, but the majority of the ride was on hard pack, pavement, or gravel that 28s totally rocked.
ReplyDeleteI rode the Ephrata Gran Fondo yesterday on the tires that came on my Salsa Vaya: Clement X'PLOR MSO 700 X 40. I don't have any experience with 23s or 28s so I can't make a direct comparison. Of course, tread pattern/depth and tire width are two different considerations. The Clements aren't very knobby, and have a center row consisting of two arrows. They roll fairly smoothly on pavement, I imagine not as fast as 23s with no tread pattern, but they absorb some shock from rough pavement. They also grip nicely and provide traction in the loose stuff, especially in the turns. In spots the skinny 23s seemed to cut into the dirt or gravel surface, while I kinda rode over the loose gravel and dirt.
There were a few miles on smooth Hwy 28 and then the paved section of the Palisades road where it could be said the 23s have an advantage over wider tires. (Depends on the study). They sure would beat the knobbier cyclocross tires.
I prefer riding on dirt roads/trails and gravel versus pavement, so for me these wider tires with a slightly raised tread pattern are ideal. They're also good for my commute.