First Look – 45NRTH Dillinger – 27.5 x 4.0 – By Seth Bell

Fat-bikers of the world with that newfangled 27.5” wheel size rejoice, for more tires choices are here!  Fat-bike.com HQ has received some of the new size offerings from 45NRTH for testing, and today we’ll take a first look at the 27.5×4.0” Dillinger 4.

The 27.5” Dillinger uses the same tread pattern and stud placement as the 26” version that riders already know and love, although 27.5” version does have accommodation for 12 more studs than the 26” tire.

Particulars of the 45NRTH Dillinger 4 27.5” include:

• 120tpi, Concave Aluminum Carbide Studded version. MSRP $210 per tire.
• 60tpi, Steel Carbide Studded version. MSRP $160 per tire.
• 120tpi Custom Studdable version. MSRP $120 per tire.
• All versions tubeless ready.
• Braced side lugs for cornering confidence.
• Fast rolling, tightly spaced center tread.

Our test tires are the 120tpi Custom Studdable (or, un-studded, if you prefer) variety, and weighed in at 1400 grams per tire.  

Because the line between ‘plus-bikes’ and ‘fat-bikes’ is getting blurry these days, we decided to get some measurements with the Dillingers on both a 50mm and 80mm rim.

Exhibit A: Dillinger 4 on a 27.5” Sun Duroc 50mm rim at 7.5psi.

• Width of tire at widest point : 90mm (3.54”).
• Height of tire from top of rim sidewall to tallest knob : 84mm (3.31”).

Exhibit B: Dillinger 4 on a 27.5” Bontrager Jackalope 80mm rim at 7.5psi.

• Width of tire at widest point : 95mm (3.74”).
• Height of tire from top of rim sidewall to tallest knob : 86mm (3.39”).

Despite a 30mm difference in rim width, the numbers changed less than expected, but the visual difference in person looks more like you’d think it would.  On the 80mm rims the Dillingers fill out considerably more than they do on the narrower rims and look like an actual fat-bike tire, where they look more rounded and light-bulb shaped on the narrow 50mm rims.  

27.5 x 4.0 Cake Eater (L) – 27.5 x 4 Dillinger (R)

We initially slapped the Dillys on our Otso Voytek demo bike, which is currently running 27.5”x 50mm Duroc rims.  Prior to mounting up the Dillinger, the Otso was rolling on 27.5 x 4.0” Terrene Cake Eaters, which fit comfortably in the frame and fork.  The respective numbers between the Cakes and the Dillys are very close, with the same width and only a 4mm increase in height. Slight as it may be, the overall increase in volume created some clearance issues on the Bluto Fork on our test bike.

Adding space for the slightly taller tires in the rear triangle was easy thanks to Otso’s Tuning Chip, which added 20mm of chainstay length and plenty of extra clearance.  Up front however, the fresh knobs of the Dillingers were a mere 6mm below the Bluto’s arch, leaving uncomfortably little room for mud, debris (and wet snow).

Despite the tight clearance up front a couple of test rides were still in order, so we hit the trails.  If you’ve ridden 45NRTH’s Dillinger tire in the past and enjoyed it, you’ll be happy to hear that the 27.5” version of this venerable tire rides, accelerates, grips and corners just like the 26” version.  The fast rolling center section of the tire keeps momentum and acceleration in the dry, and the sharp, defined knobs bite through wet Autumn leaves and hold on in the greasy sections. Unfortunately, the aforementioned Autumn leaf debris combined with muddy/greasy trails created a clearance issue with this particular test bike (running 50mm wide rims).  With so little room between the front tire and fork arch, a lot of mud and muck was bunching up under there… no bueno. Riders running 80mm wide 27.5 rims have 6mm of clearance to the Bluto cross brace but that’s still too tight for practical real-world applications in this tester’s opinion.

Long-term and Winter testing of these beauties will be passed along to another Test Pilot that has ample room for a full size 27.5×4.0” fat-bike tire.  Speaking of ample room, riders with 27.5” wheels and a Bluto be warned; even with the wider 80mm Jackalope wheel up front, there were still just six millimeters between the tire and fork crown.

The new 27.5” offerings from 45NRTH are welcomed and it’s encouraging that if this wheel size is indeed here to say, riders using them will have some more proven winners in the tire arena to choose from. Stay tuned for more and as always, thanks for reading; we’ll see you out there!