ADVENTURE BY BIKE®
Last year we introduced the Mukluk, our fatbike. For 2012, the Mukluk range expands.
Mukluk Ti is our premier product in the lineup and is available only as a Frameset. Crafted of titanium, it delivers a premium ride quality and is the only Mukluk to feature our Alternator dropouts.
Alternator dropouts allow a few different things, including wheelbase adjustment and singlespeed chain tensioning. Singlespeeds are often the setup of choice for some of the most truly derailleur-munching adventures taking place in the biking world.
Besides the kick-butt ride quality, titanium also offers a very high level of corrosion resistance, increasing the lifespan of your frame when used in wet (or wet and salty) conditions.
Mukluk 2 is offered as both a frameset and a complete bike for 2012.
Mukluk 2 is crafted of 7005 aluminum tubing that has excellent corrosion resistance. The frame receives an anodized finish for extra durability, while also removing a bit of weight. Our 2012 aluminum Mukluk frames now pass EN testing as mountain bikes.
The Enabler fork provided with the Mukluk 2 features an ED coating, which in simplified terms is the steel equivalent of anodizing aluminum. It results in a very durable finish, both inside and out.
We believe the primary goal of a fatbike should be floatation. The Mukluk 2 complete bike is spec’d with 82mm Rolling Daryl rims with cutouts for weight savings. That rim is paired with a 3.7” Endomorph tire to provide great floatation and ride quality. It also receives the premium E-13 fatbike crankset with external bearings.
Fatbikes push, and sometimes break, the boundaries of traditional bicycle engineering. Fitting big, wide tires and rims into a bicycle frame isn’t easy. Space is not unlimited. Tolerances can stack up. A millimeter here and a millimeter there, makes something that would be unnoticeable on a ‘conventional’ bike become unavoidable. Salsa chooses to spec our fatbikes with wide 82mm rims because of the floatation and performance gains.
With 82mm rims and 3.7” or 3.8” tires millimeters matter.
With our spec of the Mukluk 2, chain rub is minimal. We consider it to be at what we call ‘zero’, meaning the chain does not rub the tire, but there is no additional clearance.
The realities of fatbikes mean that a wheel slightly out of true or dished incorrectly to the driveside, or a tire that is slightly deformed, or a frame that is slightly out of alignment (even by a millimeter or two) can result in chain/tire rub. See the Millimeters Matter section at the end of this post for our thoughts on what this means and how to handle it.
Our Mukluk 3 frameset uses the same frame and fork as Mukluk 2, but with a powdercoat finish. Powdercoat finishes are also very durable.
As mentioned above, we believe fatbikes first and foremost need to provide floatation, and we spec’d the Mukluk 3 with 82mm Rolling Daryl rims. We upgraded the crankset for 2012 to a Truvativ Hussefelt model. This crankset uses outboard bearings and is of higher quality than the crankset we used last year.
Note that this specification does result in chain/tire rub when in the two easiest gears.
Last year’s Mukluk spec choice (FSA Isis crankset and 80mm Graceful Fat Sheba rims) did this as well, but was able to be countered because of the bottom bracket used. A 2.5mm spacer could be switched to the driveside of the bottom bracket thereby moving the chainrings outboard and eliminating chain/tire rub.
Our 2012 Mukluk 3 spec does not allow this spacer-trick option. The crankset uses external bearings and the spindle is not long enough to allow an extra spacer to be added to move the crankset/chainrings outboard. In addition, the switch from an 80mm rim to the 82mm rim widens the tire even more, further complicating the matter. This results in the chain/tire rub mentioned above.
Again, Salsa chooses to spec our fatbikes with wide 82mm rims because of the floatation and performance gains. As noted earlier, this puts the rider on a high performance rear wheel immediately and doesn’t push them to upgrade to a wider rim once they realize the benefit of floatation.
In their relatively short history, fatbike riders have (and continue to) use modified setups to make their bikes work the way they want them to. There are several ways to deal with this chain/tire rub, all of which are common with fatbikes. Keep reading the Millimeters Matter portion of the post for more on this.
We feel our 2012 Mukluk lineup is a great addition to the fatbike world, and we know they are encouraging more folks than ever to try these incredibly capable machines. They truly do ride where other bikes can’t.
Fatbikes are complicated machines. Cramming wider stuff in just doesn’t work. In fact, our sister brand Surly’s original 65mm Large Marge rim and 3.7” Endomorph tire standard did not develop by accident. Those sizes were determined because they would allow full use of all gears without creating chain/tire rub.
80mm rims (and wider) and 3.7” tires (and wider) complicate this matter. To put it simply, there is no room for the chain to move past the tire without touching it. But keep in mind that those wider rims and tires do create greater floatation and tire performance, thereby creating a finely honed double-edged sword.
As mentioned earlier, there are commonly used methods to eliminate this chain/tire rub. (NOTE: The wider your rim and tire get, the more trade-offs you need to make to avoid chain/tire rub)
1) Dish the wheel slightly to the non-driveside of the bike. By moving the rim 4mm or so to the left (for an 82mm rim and 3.8” tire), it creates slight clearance for the chain to avoid the tire. This slight wheel dishing is unnoticeable when riding the bike and retains full use of all gears.
2) Truncate your cassette. We posted a blog on this earlier this year because this solution is so commonly used with fatbikes. By removing one or two rear cogs (normally the smaller ones), shifting the remaining cogs outboard, and then limiting the rear derailleur travel, it creates slight clearance for the chain to avoid the tire. This does remove a couple gears from your cassette but is the preferred method of many fatbike riders (including the majority of us at Salsa).
3) Change crankset/bottom bracket. As obvious from this post, the crankset/bottom bracket combo you choose will have a dramatic affect on whether or not you experience chain/tire rub. There are a few options available that can help minimize this, including the higher end E-13 and Surly Mr. Whirly MWOD cranksets. You could also downgrade to the FSA Isis crankset/bottom bracket to help minimize chain/tire rub.
4) Downgrade your rear wheel. Switching to a 65mm rim with a 3.8” tire will create clearance for the chain to move past the tire. But it will also decrease floatation and just as importantly the ride quality of the tire. In our experience, 3.8” knobby tires perform better when mounted to 80mm rims than 65mm rims.
With Specific Regard To The 2012 Mukluk 3 Chain/Tire Rub Situation
Our 2012 Mukluk 3 spec was chosen intentionally to deliver Floatation, Quality, and Price.
We feel that fatbikes should have rims that are 80mm-wide or wider to provide the floatation they are designed for. We believe a 65mm rim is a down spec and more importantly a downgrade in performance. For the consumer to upgrade to a wider rim will eventually be a very costly endeavor. We prefer to start them off with what we consider a proper fatbike wheel.
The crankset we chose is a higher quality than the previous year’s model. We believe it offers better performance and value in the long term. We chose not to down spec to the previous year’s crankset. We also didn’t choose to spec the highest end cranksets on the market because of the effect it would have on price.
No good fatbike is cheap, but we did try to create the nicest bike we could at a price that would hopefully help more people make their way into the fatbike world. Fatbiking is something we think more cyclists should take part in, as it can be an incredibly unique experience, different from all other types of cycling, once the rider realizes the unique capabilities of these machines.
We Own Our Decisions
We’ve seen a mixed response to the chain/tire rub situation of the 2012 Mukluk 3. Some are okay with the solutions of re-dishing the rear wheel or truncating the cassette. Others don’t like either of those solutions.
If you purchased a 2012 Mukluk 3, we will work with you through your Salsa Authorized Dealer to make you happy with your purchase.
The feedback we’ve gotten on the Mukluk 3 spec has been an interesting lesson.
Not choosing one of the methods listed above still presented two commonly used options to the end consumer, and gave them the ability to choose the one they preferred, but many folks have not been satisfied by this.
For that we apologize.
In the future, we will avoid chain/tire rub by choosing to truncate, dish differently, spec a different crankset/bottom bracket/rim, or come to market at a different price.
Thanks for reading this rather long post. We hope this helps you understand the 2012 Mukluk lineup, some of the inherent design challenges fatbikes present, as well as why we made some of the decisions we did.
Now please go enjoy riding a bike.
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I love being outside. I prefer to ride on dirt. Or snow. If I was born a hundred years earlier I might have been a polar explorer. There's a great natural world out there to see, smell, taste, listen to, and experience. Life slows down out there and the distractions we've created will disappear if you let them. Give me a backpack and let me go.