Convert hardtail mountain bike to gravel bike?

4 min readApr 22, 2020

If you’re here, you’ve been doing what I did over the past handful of months: pondering the reality of turning your hardtail into a gravel bike.

What have I done?

I converted my 2013 Diamondback Overdrive Expert (29er hardtail) into a “gravel” bike. Kind of.

Why did I do it?

Want: I want drop bars, 700x50mm tires or wider (29x2.2 would be perfect), and disc brakes. Basically, I want an affordable alternative to a Salsa Cutthroat. And XC Hardtail is basically already there with the handlebars being the primary difference.

I love bike touring/bikepacking, running ultramarathons, and general off-pavement adventure. I prefer drop handlebars over flatbars, every time, although my biggest reason for this converstion is tire width.

Why this bike? My Overdrive components were already worn out, and I crashed, breaking the rear derailleur! It was a convenient time since I wanted to replace everything anyway.

Is this 29er mountain bike totally capable, as is, for what I want to do? Absolutely!

Although, after giving flat bars an honest try, the speed at which I go down singletrack is manageable and fun with drop bars. Bikepacking is my goal, not necessarily shredding the gnar.

Is a 700c road bike with 28c tires capable of exploring forest roads? Sure! I’ve done it for years and am beyond sick and tired of getting flats. I’ve done epic long rides over gravel with my skinny tire road bike, but the pace is slower and caution is higher. … So here we are.

How did I do it?

What am I keeping?

Frame, 2013 Diamondback Overdrive Expert (aluminum) size large.
Wheelset, 32h SL-7.
Headset, the stock FSA stuff.

What did I buy?

$45, Microshift Advent Bar-End 9-Speed Shifters.
$58, Microshift Advent 9-Speed, Long Cage Rear Derailleur.
$35, Microshift Advent H08, 8-Speed Cassette, 12–42t.
$25, Tektro RL520A Linear Long-Pull Brake Levers.
*** Road and MTB levers/brakes have different pull ratios. I am keeping the stock Hayes disc brakes that work with these long pull levers.
$70, Shimano ZEE 1x GXP Crankset, 175mm, 36t.
$25, Sram GXP 68/73 English Threaded Bottom Bracket.
$125, Salsa Firestarter Rigid Fork.
$36, FSA Ns Adventure Drop Bar 46cm.
$20, UNO 0* Short Stem, 35mm Stack.
$8, FSA Headset Star-Fangled Nut.
*** Don’t forget this! I did. I was an idiot. Don’t be like me.
$100, Maxxis Ikon, 29x2.2 3C/EXO/TR.
(Depending on the life of these, I am highly considering Continental Race Kings 29x2.2, with their ProTection and Black Chili. Thoughts? Leave a comment.)
$9, Sram PC-830 6/7/8 Speed Chain w/ Powerlink.
$50, Shimano PD-M520 SPD Clipless MTB Pedals.
$12, Soma Thick and Zesty Synthetic Bar Tape.
$11, Maxima Waterproof Grease.
$17, Stan’s Notubes 16oz Tire Sealant.
$13, Stan’s Notubes Time Tape, 21mm x 10-yard roll.
*This “tape” was absolute garbage and I resorted to gorilla tape ($5), which was so much easier and worked like a charm!

Total investments

$250, previously owned Diamondback Overdrive, about two years ago.

$659, everything else is new for the conversion.

Total Build Price: $909

Post-Build Thoughts

If I did not already own the Overdrive, I would have bought something new and in the $1000 range.

Embracing the option to take what I own and replace everything with new parts, even some off-brand, has been a fun project!

Fully knowing I will buy a proper gravel bike soon, this is enough to satiate the itch on a somewhat decent budget. It also has a slightly different purpose than a dedicated gravel bike.

All that said…

Key Takeaway: With this project in mind, I would not go onto eBay/Marketplace/Craigslist and buy a used bike frame. If you already have a hardtail sitting around, this can be fun if you want a project.

A new entry-level bike that’s solid for all the adventures can be had for the same price, or slightly more, if you want to avoid the fuss. (Trek Marin for a hardtail mtb example)

Great sub-$1000 options:

$950 Salsa Journeyman Claris ($1200 for Journeyman Sora)
$750 Poseidon X
$950 Poseidon Redwood
$900 State Bicycle Co 4130 All-Road

There are countless other brands out there with competitive bikes and prices, but just to toss out the results of a quick Google search.

Future Projects

Late-90s Diamondback Centurion TG Expert road bike.

I’ve had this bike a long time and it’s nostalgic, aged with normal wear from heavy use. Nothing is malfunctioning, just in need of replacement.

The bottom bracket could use a refresh, cable housings are wearing in spots, and I want to convert away from down-tube shifters if it’s an easy thing to do. If I can trade out the Shimano RX100 drivetrain with an exact replacement then I absolutely will; otherwise, I will try for Shimano 105 all around. Also, both wheels currently have a broken spoke, so they need to be rebuilt anyway. Converting to 10 or 11 speed would be sweet, as well, but I enjoy the 52/34 rings upfront.

1960s Peugeot steel frame, the model unknown.

Custom handpainted by the legendary Rob Roberson, in California.
I got this from my very gracious boss and I’m excited to give it a refresh! New seat, tires, and bar tape are on the way. I am tempted to find period accurate handlebars that aren’t so narrow but am not in a hurry to alter anything.

Ok, that’s all. Now go ride whatever and wherever you want!