Reader’s Ride(s) – Reid’s Upgraded Mongoose Dolomite

Reid sent in the first image of this story as a Wallpaper Wednesday but when I sent him a request for a bit more info on his Mongoose Dolomite i realized there is a Reader’s Ride(s) story here.

A lot of times I think of Reader’s Ride(s) stories as seeing all the high-end, blingy things fat-biker can do if they have the resources but that most of us can’t, or don’t want to, afford and believe me, I love those high-end bikes but Reid’s story about his Mongoose Dolomite reminds me that a lot fat-bikers out there are just getting their feet wet in the fat-biking community and are just beginning their journey. Fat-biking is about getting out there no matter what steed you ride! Take it away Reid


This is my Mongoose Dolomite in the Santa Maria, CA riverbed, under the Hwy 101 bridge

The Dolomite was an impulse buy online after seeing a single-speed coaster Mongoose in a Walmart market. Hadn’t even seen a fat-tire bike before and hadn’t even ridden a bike in 20 years. Yes, it’s heavy, but it’s good exercise for a senior to build the quads.

It also gave me some bike mechanic practice since it arrived with almost no grease, and a number parts needed to be upgraded.

I knew that I couldn’t expect much for $212 and free shipping. I didn’t bother to read reviews and wasn’t ready to spend a lot more, not knowing if I would even like riding one.


The first thing I noticed was that braking pulsed because the rotors were not ground properly. I put up with that for a while. When break-in didn’t help, I installed Shimano SM-RT56 Disc Brake Rotors (6-Bolt, 160mm) and  Shimano BR-M375 Disc Brake Calipers. Was tempted to go hydraulic, but didn’t want to spend the money for possible over-kill. Mechanical works fine for my riding.

After the first ride, the seat had to go. Replaced it with a Sunlite Cloud-9, Bicycle Suspension Cruiser Saddle, Cruiser Gel that you can see in the first photo.


Other things that went bad quickly is that trail grit got into the BB, so I installed YST Sealed BSA Cupset w/Bearings (English Threads). Pedals also got gritty, and replaced those with RockBros MTB BMX pedals. (Had to replace the left crank arm after rounding it out because I didn’t tighten the nut enough when putting things back together!)


Shifting was OK at first, but the twist shifter became a pain (literally), so next upgrades were a Shimano Acera SL-M310 Rapid Fire Shifter and Shimano RD-M410 Alivio SGS Rear Derailleur (7/8-Speed, Long Cage).  The original chain was worn out by that time, so I replaced it with a KMC Z-72 7-8sp.

I got hand numbness with the original grips. Weanas® 2X New Generation Gel Inserts Shock Resistance Ergonomics Comfort Design Bicycle MTB XC FR Handlebar Grip with G2 Screw Lock took care of that.


The latest mod was a SHIMANO MF-T31 MegaRange 7 Speed Freewheel 14-34t, to give me a better low for going up the levee trail ramps.


I can’t think of anything else to hang on the handlebars of my “clown bike”!   ?

All that has probably added up to near, if not over, the cost of the bike.  😉  It gave me another hobby in retirement and I am happy with the end result. Yes, it’s still way too heavy, of course, but that adds to the workout that I get. :). Plus, a fat-bike is a good conversation topic when I meet people on the levee.

Thanks a lot Reid!

If you have a fat-bike that you modified or built up yourself that you are proud of, let me know. Just shoot me a note at! You may see your rig in a Reader’s Ride(s) feature!


17 Responses to Reader’s Ride(s) – Reid’s Upgraded Mongoose Dolomite

  1. Tony February 17, 2016 at 12:14 am #

    Always wonder if you’d be better off buying a more expensive bike to start with. Result roughly the same but lighter?

    • Madcityspecv February 17, 2016 at 11:15 am #

      I view it as a valuable option for those who can’t easily spend ~$1000+ on something they may not like. i bought a used Mongoose Beast SS fatbike a year ago, and used parts bin engineering along with a generous and friendly LBS to make it rideable. as a road cyclist, i wanted to give it a try without spending my kid’s college fund, and my build fit that. overall i have less than $200 in the bike which cost me ~$100. I had so much fun that i scrimped and saved all year, and will be making the leap to a “real” bike this spring. something i never would have done with the price barrier that “good” bikes” sit behind.

      • Chris M December 22, 2016 at 7:58 am #

        The Mongoose is a “real bike”!

  2. SuperSolo February 17, 2016 at 7:02 am #

    Great write up.

    Always interested to hear about the tweaks people make to ensure the bike is truly their’s.

    To the owner – enjoy and happy trails!

  3. jerak February 19, 2016 at 3:27 pm #

    This is my favorite “Reader’s Ride(s)” in a long time.

    I admire Reid’s pragmatic approach, only upgrading the stuff that wore out or didn’t meet his comfort needs, and the parts that were a casualty of the process of getting familiar with being your own mechanic.

    To me, this is way more legit (and interesting!) than the Uber Bikes that unfortunately sometimes seduce me with the idea that it is somehow the bike and not the riding that makes me happy.

  4. skota March 1, 2016 at 11:20 am #

    Bravo, nice work Reid!

  5. Reid March 2, 2016 at 2:18 pm #

    I did one more upgrade and the bike lost 8 pounds in the process. Installed Vee Rubber 26 x 4.0″ 120 TPI tires and Vee Rubber tubes. The original tires were 6 pounds each and the thick tubes were an amazing 2 pounds each! The Vee Rubber items weigh half that.

    Traction on hard surfaces improved greatly, plus now has a smoother ride. Got a nice speed improvement, too. 🙂

  6. Bravo 25 April 6, 2016 at 9:10 pm #

    This is an insightful and helpful article. It is a pleasant and enjoyable read. Thanks ! Happy Trails !

  7. Adam Hartley May 19, 2016 at 8:42 am #

    Man this is great! Best reader’s rides in here to me. I just scored a steel department store fat bike on Craigslist for $100 and have been stripping it down and replacing all the pig iron with aluminum spare parts. I’m definitely looking to swap the tires after reading your update! Keep up the good work!

  8. Reid June 27, 2016 at 9:29 pm #

    Since I am a flat-lander, I made another project to get some more speed on the Dolomite. The light tires and tubes allowed me to use some taller gearing. I did some browsing to see what worked for others and added:

    1) Shimano Altus FC-M311 Bicycle Crankset – 175 x 42-32-22 Square Tapered

    2) Shimano Acera SL-M310 Rapid Fire Shifter

    3) Problem Solvers Direct Mount Front Derailleur Adapter for Moonlander 34.9mm clamp w/ shims

    4) Shimano XT M771D Direct Mount Derailleur

    That also gave me lower gears, so I went back to the non-Mega Range freewheel.

    I have hit a little over 21 MPH on level surface (although not for very long.) 😉

  9. Rich July 7, 2016 at 11:12 pm #

    Nice bike and article Reid! I bought a Dolomite this spring with exactly the same idea – try fat biking without having to mortgage the house. I’ve done similar upgrades to mine – seat, levers, derailleur, shifter, bars mostly by pilfering bits off my old mountain bike. I added the Megarange freewheel and a 22t chainring inside the stock 36t for offroad use – $6 in parts from the local bike recycling place. I probably spent more on bike tools than I did on parts. My Vee 8 fat tires should be here in a couple of days so I’m looking forward to shedding those extra pounds too. I’m having a blast with my Dolimite – I probably will never buy a “good” fat bike because this one is 90% of the fun for 10% of the cost!

    Ride on Reid!

  10. Chris August 7, 2016 at 7:10 am #

    Are the pedals 1/2″ or 9/16″?

  11. Chris M December 22, 2016 at 7:41 am #

    Nice write up. I’m both a road and mountain bike rider.

    This bike is within several pounds of fat-tire bikes that cost sometimes thousands more, I personally can’t justify/won’t spend thousands on a bike that doesn’t really perform much different than a $250 bike.

    You answered my questions on reducing weight. Replacing components and tires (wow!) to reduce weight!

    I see many Mongoose bikes on the trails. I think it’s good that people are taking to exercise in the winter and the initiative buying a reasonably priced bike and exploring the off road world.

    Fat tire bikes are absolutely necessary in deep snow.

    Studded narrow bike tires work great in ice, but fat tires are much better in fresh deep Minnesota snow.

  12. Charlie Sweet January 3, 2017 at 11:35 am #

    I went a step further I replace the 7 speed free wheel with a 9 speed one I found on ebay, swapped out the older shifters with a set of Sram X0 twist grip, Sram X9 rear derailleur and a shimano SLX front derailleur with a Problem solver mount Found a 100mm 2x crank and aluminum fork, Lighter bars and stem, New tires and drilled wheels topped it all off with Shimano hydraulic brake set. I dropped almost 12lbs with all my up grades. Now mind you a lot of these parts were used or I had the laying around. It is a great riding bike.

  13. Chris M January 4, 2017 at 7:36 am #

    Cool. I’m buying a Mongoose. It’s worth a try!

  14. Michael Nantz January 15, 2017 at 7:28 am #

    I’m curious for the ones that have added the front derailleur, where you found the mount for it? I checked at my lbs and they didn’t know of one that would fit my Mongoose.
    Has anyone thought about adding a suspension fork?

  15. exmelin September 2, 2022 at 3:05 pm #

    hi everybody//can someone tell me what is the length of the pedal axle on the dolomite?thanks

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