08 March, 2016

Dirt Wizards on smaller Piolets

by Scott

Having had emails about the largest tire size that will fit in the 29'r models of the Piolet, time came that we did the research into large tires on the extra small and small sizes. Since I have a small, I brought it in to be the test mule for this investigation.

For my off road riding, I have been using the Maxxis Ardent 26 x 2.4 tires. For the riding I do, mostly single track with a decent amount of roots and rocks but no huge drops or such, they work great. I keep the pressure low, so a ton of traction is the result. Mounted on a 26" Escapade rim (28 mm outside width) they measure out at 2.3" (58 mm) when inflated to 25 PSI at 82 ft above sea level.

Finding a tire that falls between 2.4" and 3" isn't easy, but we managed to snag a Surly Dirt Wizard for the experiment. We knew the 3" would not fit, but the 2.75 held out hope. It is labeled as a 26 x 2.75 " tire; when mounted to the Escapade rim, it came out to 2.63" (67 mm) when inflated to 25 PSI at 82 ft above sea level. So it's not a lot bigger than the Maxxis tire but enough so to be significant.
Looking at the frame, we figured it would fit. Installing it on the front of the bike, I found there was lots of room at the sides of the fork and around the fork crown. Success!!  I took it out for a quick spin around the parking lot and it felt fine. Now on to the rear.
Looking at the rear, Igor and I figured that the frame would fit it, but my triple would not. And we were proved right. The wheel and tire fit fine, but I could not shift down into my inner ring, as the inside of the front derailleur touches the tire. So it won't work with my current set up; but if I went to a different set up, a 1x or a wide double, I could make it work.

I'm not ready yet to ditch the triple, so in the meantime, I'll go back to the Maxxis tires for my off road usage, but this remains an interesting tire to try should the need for a really wide tire come up.


George said...

FYI on a wider rim (I'm running the 26" Dually on a size S Piolet) there is some chainstay rub from the shoulder lugs on the Dirt Wizard. Currently I've switched back to a 2.4" tire, but for what the Piolet is designed to do, it might be worthwhile to check out the Surly ET tire, which they describe as a "heavy-duty offroad touring tire". Will let you know if/when I try that out.

teamdarb said...

Thanks, you guys keep making my life harder.

Mark Holm said...

How wide is your bottom bracket?

Neil Hodges said...

Couldn't you use a longer than intended spindle if you had a square-taper triple?

VeloOrange said...

@ George- Those tires are the next ones I want to get for light-racking tours this spring and summer in the Mid Atlantic and hopefully beyond. They look like a great tire for gravel road exploration.
@Mark Holm- no idea of the BB length. The shell on the Piolet is a 73 mm so I used a Deore 9 speed triple two piece crank with a Hollowtech BB that comes attached to it.
@ Neil- the longest square taper BB in a 73 mm shell size I can quickly find is 122.5 mm and I don't know if that would be long enough to clear the Dirt Wizards.

Jean-Francois Caron said...

My current bike is kind of a poor-man's Piolet, I built it last year before I'd even heard of the Piolet. It's a 1993 Miyata Elevation 500 with oversized welded steel tubes. Every single part was replaced except the 1 1/4" threaded headset and the seatpost. It's got 3 racks, drop bars, and huge wheels.

On Big Fat Mammoth rims I can fit Maxxis Hookworm 26x2.5" tires with about 0.5mm of clearance on the rear triangle. Knobbies have to be a bit smaller.

I'm glad to see if I need to replace the frame, I can probably just get a Piolet and do all the same stuff.

Jofus Braylor said...

You don't need to quote the altitude when stating your tire pressure and the measured width, because your pump is reading gage pressure- i.e. the difference between internal pressure and the atmospheric pressure. If it's filled to 25psi at 5,000 feet, or 25psi at 80 feet, the tire will measure and ride the same. (of course, if you fill your tires to 25psi at 80 feet and then ride to 5000 feet, they'll gage a whopping 27.5psi, but you might be too tired to notice by then)

Alan Sotelo said...

Is it possible to fit 700x35c knobby tires in this size? Thinking this could also double as a skinny knobby tired dweller. - Alan