Fat-bike 101 – Rims

Original 65mm Large Marge in the center flanked by the narrower 47mm Schlick Northpaw and the wider 100mm Surly Clownshoe.

This article is part of the Fat-bike 101 series and is intended to help new fat-bike owners, and potential fat-bike owners, with some of the questions they may have about fat-bikes. In addition, it is a chance for experienced riders to add comments to help our new brethren enjoy all that fat-biking offers. Consider these articles as conversation starters, not exhaustive explanations!

Just like the development of fat-bike tires, fat-bike rims began with a few soft-condition riders looking for a wider footprint for their bike tires and not finding any thing commercially available. Early fat-bike rims were actually a pair of rims welded together to create a wider platform for the custom tires folks were making. Eventually the 44mm SnoCat rim (still available!) was produced as a way to give MTB riders of the time the widest footprint possible in a conventional MTB frame.

With the introduction of the Surly Large Marge, a double wall, 65mm rim, the tire/rim combo became too wide for conventional MTB frames and, building on an idea from the early days of fat-bike builders like Mark Gronewald, the Surly Pugsley became the first commercially available fat-bike sporting those same 65mm Large Marge rims. We’d still consider the 65mm rim to be the “standard model” as far as rim width goes allowing a wide variety of fat-bike riding in lots of different conditions with both narrower rims and wider rims trending towards more specialized needs.

Large Marges were the standard of the fat-bike industry for a few years but today’s fat-bike riders are looking for lighter weight in all fat-bike rim applications. You will see lighter, singlewall rims like the Surly Marge Lite, Fatback UMA 70 that shave several hundred grams off your wheel set. Wider rims like the Rolling Darryl, Uma 90 and Clownshoes also adopting lighter, singlewall construction.

With more and more people riding their fat-bikes year ’round there has been a resurgence in narrower rims that can still run the fat-bike standard 26 x 3.8 tire. Sandman uses the 47mm Trialtech rim, Schlick Cycles developed the 47mm Northpaw-S rim and 616 partnered with All Weather Sports to offer complete wheels built with SnowCat rims and (44mm). The narrower rims certainly reduce weight and still offer much of the benefits of the fat-bike tire.

Frankly, I did not want this to become a history lesson or a chronological listing of the development of the fat-bike rim, or fat-bikes in general for that matter, although that would make for a good article! The main point here is that, depending on how you ride your fat-bike there is bound to be a rim that will suit your needs. In fact, many fat-bike riders I know have two wheelsets so they can choose the set that will work well on a given ride!

What’s up for the future?

Well, we’ve heard rumors of fat-bike rims getting as wide as 160mm but at some point the size constraints of a conventional drivetrain will be reached.

On the narrower end of the fat-bike rim spectrum, 44mm is about as narrow as you can go and still run a 26 x 3.8 tire. Narrower than that and you are simply running a wide MTB rim/tire combo but we think there will be more players on the 45mm-50mm range as fat-bike riders turn on to all-season fat-bike riding!

Here is a listing of rims we know to be currently available and that are intended for the fat-bike market from narrowest to widest.

If you are an experienced fat-biker please consider leaving a comment below to help newbies get maximum enjoyment from their ride.

If you have a topic you’d like for us to open up a dialog on, please send us a note to fatbike101@fat-bike.com and we will do our best to cover it.

About Greg Smith 1127 Articles
Greg Smith, known to many site visitors as Sven Hammer, founded Fat-bike.com in 2011 and the site quickly became the #1 online community for all things Fat. You can currently find Greg outfitting Everyday Cycles; a Milwaukee, WI retailer of gear for fatbikers, adventure cyclists and urban assault riders.


  1. I was just at the Surly site before reading this post and noticed they no longer list Large Marge rims. ?? Have they been discontinued? Has anyone heard this?

    Since buying my Pugsley in 2006, I’ve put 4,000 miles on a pair of Large Marges exclusively on snow. I got a bit teary eyed thinking of them as part of Fatbiking history, and now being gone.

    Oh well, I did upgrade to a pair of Rolling Darrly’s this past fall and my LM’s are collecting dust.

  2. from an Australian, industry point of view…

    we offer our build kits with 80mm rims as “std”. With 65mm or 100mm as “options”.

    Surprisingly… the main “option” taken up is the switch to the lighter, narrower 65mm rims.

    And a lot of those are bikes going to riders planning on riding in the Simpson Desert Bike Challenge. So clearly, those people are more than happy with the floatation of the slimmer rim/FAT tyre combo.

    But then… we are very light on when it comes to snow down here.

  3. Just to pick up the note on drive train limits
    Running a jack shaft system in the manner of Brooklyn machine works amongst others is a option
    Actually I write this hainbrink ? Bike I think used this too for their ballon tyre bikes
    Anyway I was running 26 x3 on the double wide rims 10 years back as the fattest wheel set I could run and with siesmic hubs too
    Strong legs back then

  4. Please continue to do more “101” articles.
    They “101” articles make the decision process go quicker.

  5. There was actually a very early 80mm rim, I believe it was called the Remolite (?) which was produced in the early 90’s maybe the late 80’s. It was before even my time riding in the snow, and I guess even back then you had to know someone who knew someone to get your hands on them… there was no internet then to share information on unique products for unique uses like this.

    The folks who did this also made a tire very similar to the Enduromorph. So Surly did not invent the truly fat tire, they copied an idea that was clearly ahead of its time… But I will give Surly credit for giving it legs!

  6. Big Boggy Beach Begs Big Beefy Braaaaptacular rims.

    Tight Twisty Trails Tailor To Tweener rims.

  7. I had the LaGrange General Store build up a 9:zero:7 fat bike for me with the purpose of being an all season off road bike.

    Andy over at the “store” got it totally right and many folks saw this bike in the shop while it was being built…

    real running weight with pedals and wb cages and small tool bag of 30 lbs…

    Andy choose the large marge lite combined with hope hubs…and a carbon fork and it is a hot bike that did not disappoint…

    Andy just built me up a super set of 2 niner wheels for that bike with hope hubes and stans no tubes rims shod with some schlabbie tubeless slicks for gravel grinder adventure rides this summer…..

    Got to say for me anyway that 9;zero:7 has some dialed in frame geometry…..

    1400 plus miles on my fat bike since Jan 3…..gravel roads and that 9:zero:7 frame with those new wheels is a hot set up…

    riding the kettles for me will be fat…..gravel grinding for the skinny and one bike….


    • One benefit of the Fatback Uma rims is that you can easily set your wheels up tubeless since they have a bead lock. You can do it on most of the wheels above with some tinkering, but the Uma’s are definitely the easiest and most reliable. I have been running tubeless the last 2 winters on both a set of the Uma 70s and 90s and they ride great, especially when compared to running the Surly fat tubes. Also, haven’t had a problem with cold since I have been out in temps down to -30F with no problems.

    • Are you running skinny wheels on the fat bike? If so, what drive train? I have an interest in a fat bike for winter that I can change to a summer commuter with smaller wheels and tires.

  8. Niagra Cycles sells Weinmann rims in 65, 80, and 100 widths, 36 or 32 hole. Very similar to the ChoppersUS rims. They are double wall, heavy but can be drilled. No bead Lock but very reasonably priced.

  9. “rumors of fat-bike rims getting as wide as 160mm”
    Nice to hear, but where to buy? Does anybody know who’s gonna produce these rims and appropriate tires?

  10. Hey guys,

    amazing tips and information!!!

    I’m from Oz and here there’s not too much dealers/retailres to buy a Fatty. But I found a shop that makes their own bike and their rims are:

    Front: 30MM and Rear: 100MM

    What do you think of this combination. ??


  11. Anyone have experience running DHL100’s on a Moonlander? I have an application that calls for 36 holes and I don’t know of another option.

  12. I posted this question elsewhere but realize this may be the appropriate place for it.

    I am riding an older Pugsley with a set of Large Marge 65m and Nate 3.8
    Been thinking about swapping to a lighter rim and maybe larger rim width.

    – but I am wondering how wide is too wide…80-90-100.
    I think a 100 rim may just fit in the frame but then the tire will dictate my limits?

    How much does the tire height/ width change on different rims?

    I am very interested if someone has tried doing this?

      • Thanks Gomez!
        That was just what I was looking for…

        I was already thinking about the 4.7 Snowshoe because I heard it was closer to 4.25″ and would work on the Pugsley… also It’s a much lighter option than my current 72tpi Nate’s.

        The Vee Rubber H-Billie 26 x 4.25″ may be an option for me also.

  13. Any info on the size of the mongoose malus rims? Looking to put some color floaters but will only fit 55-90mm. Thanks

  14. I’m still using my first fatbike(Boris) and just turned over 1100 miles for the year on 80mm rims and 4.0 fat-B-Nimble tires.

  15. hi there, I am looking to convert my fat bike to having slightly narrower rims so I can also use it as my daily commuter. I am interested in the schlick northpaw rims. Will these still fit my vee rubber 4.0 tires as well as narrower commuter type tyre, maybe like 2inch tyres, or should I just make up another set of wheels 700c or 29er 32h so I can run a commuting tyre?

    • Greg, the measurements are for front and rear axle spacing on certain fat-bikes. The front is actually 150mm x 15 and was the front axle spacing adopted by the RockShox Bluto fat-bike suspension fork while the 197mm x 12 is the wider of the two common, symmetrical fat-bike rear axle measurements when used with a thru-axle. A 190mm Q/R is the same. These are commonly used on fat-bikes that support the fatter 5″ tire platform.

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