For all the hapless fatbike Google searchers out there!
If you’ve landed here, there’s a good chance you’re looking for this info: will a Bontrager Barbegazi 4.7″ tire fit in the back of a Surly Pugsley?
The answer is yes. Barely.
I’m running a mostly stock Surly Pug SS from 2015. The rims are Marge Lite 65mm, with Surly rim strips and tubes. Currently, I am running the Barbegazi tires front and rear. My Pugsley has a Moonlander front fork, so front clearance is fine.
The tires have 10-12 PSI, although I tested them from 5 PSI to 20 PSI with no rub. Against my better judgement and the manufacturer’s warranty, I pumped them up to 30 PSI and got a very slight rub on the driveside chainstay, but only at one point on the tire (it’s slightly uneven). It’s close!
As you can see, neither chainstay rubs. There’s about 5mm clearance on the non-driveside and 3-4mm of clearance on the driveside, with about 1-2mm of sway in the tire. That might go away after I’ve ridden them a bit.
I have the wheel slammed as far forward in the dropout as it goes, without Monkey Nuts.
The chain clearance is about 2-3mm. I am running an 11-36T cassette with the stock 94 BCD x 33T front ring, spaced ~1cm inboard using the chainring bolt spacers that come stock on the Surly Pug SS. My crankset is the stock Surly O.D. crank. Here’s a picture in the lowest ratio, 33×36.
My LBS is a Trek dealer and someone upgraded a Trek fatbike right out of the gate with 45NRTH tires, so I picked these up off a stock build. According to Trek, they come in at 1300g, only 50g more than the Knard 3.8″ tires, both being 120 TPI. That’s an impressive weight for a substantially knobbier tire. These are also tubeless ready, which is good, since tubeless is in my future.
They’re nice tires, but it’s too early for a review. Stay tuned!
P.S. Since someone usually asks, that’s a Bontrager Backrack Deluxe rack up front, and I filed the struts to round them out so they’d fit on the bosses near the crown of the Moonlander fork. Without filing, the struts have a slightly squared-off end that wouldn’t squeeze against the fork.
Editor’s Note: After 24 hours of pushing around trying to get the Barbegazi to rub, it did rub the chain. If I was still running singlespeed I’d say it’s cool, but as-is, I think I’m going with a different tire. Thank you Laughing Dog for letting me test these before committing!