Stan’s Mercer Bikes Karoobaix Disc All Road

I’m here in South Africa, documenting the Karoobaix, a 400km race through the Karoo Desert and naturally, while here, I’ve been documenting a few bikes from the event. While I’m compiling photos from the race itself. The first bike is Stan’s Mercer Bikes…

Stan is the organizer of the Karoobaix and the Tour of Ara, both races explore the vast Karoo desert outside of Cape Town. For South Africans, there are enough mountain bike races, but no dedicated “gravel” races, where dropbar exclusivity looks to separate these races from other, XC MTB-oriented stage races like the Cape Epic.

This bike was made by a South Africa builder named Mercer Bikes. Stan wanted an all-road bike, complete with rear rack mounts, clearance for big tires and a beautiful custom rack, which utilizes the face plate drilling of the Thomson stem. Stan then modified a bag he found online to fit on this race. While the rack is one of the most unique of its kind I’ve ever seen, by far, my favorite detail is the most low-fi, the amazing hand painted decoration by local artist Black Koki.

While there’s much more to come from my time in South Africa, including my Karoobaix Reportage, I wanted to give you something to whet your appetite in the meanwhile…

  • Anthony M. Garcia

    That rack is awesome.

  • Hydration on point

    • I had to carry 4L yesterday and I still ran out of water… twice! Desert riding is serious. hah.

  • Marc Gasch

    Obvious question: WHERE DO I GET THAT RACK! :-) I can see myself carrying cameras in there!

    • Mercer Bikes made it and I don’t think he ever wants to make one again. haha

      • Marc Gasch

        Damn! :) Have fun down there, love it!

      • Damien Milazzo

        Hey John, I asked this in the main thread, but thought it might be best to reply to one of your comments. What bag did Stan purchase. I have a mind to make a similar rack, but cannot find a suitable bag.

        Thanks and Happy Trails!

  • that probably the most innovative rack design ive seen…ever.
    simple, minimal, functional. bravo!


    John, Have a blast in South Africa! A very unique bike for sure!

    • It was fun until my knee blew up. :-(


        Ah man so sorry. I have a 50 year old knee…I know the feeling. Get better soon!

  • Nicholas Tingey

    Love me some S&S couplers. Nice build!

  • Nealipo

    One of the best bikes ever showcased on this site.

  • Kawika Samson

    Super sick paint


    Somebody should think seriously about making this rack, perfect for randonneering too…
    Nice pics, as usual!

    • Jared Jerome

      It looks like someone already did…

    • Travis Brunner

      That’d be quite the undertaking, you’d only be able to use one specific stem. If it were to be one off custom made then the builder would have to have various different stems or the consumer would have to send the builder the stem they are planing to use bc various stem angles and various stem bolt configurations would make it a giant headache

  • Incredible, in every detail.

  • bikecow

    If I remember correctly, I think I saw this one in the comment section a couple years ago. Glad to finally see a complete photo set of this thing, super cool!

  • Newb question: what are those metal parts in the top and down tubes? I’ve seen them from time to time. Are they a way to break the frame apart for travelling/packing?

    • AaronBenjamin

      Yes, they’re called S&S couplers.

      • Ahhh, cheers. Saw a comment below but didn’t know what it was referring to. Thanks.

  • AaronBenjamin

    That rack is the business! I always thought handlebar bags just needed a little extra support over rough stuff – that is it.

  • Best paint job! Very well captured.

  • Andrew Demack

    Appetites are what we whet (i.e. sharpen). Wet your whistle means have a drink. Fabulous bike, cool rack.

  • Brian Sims

    The rack is dope for sure. Curious about the cage on the seat tube. What is that?

  • dan scheie

    I was scrolling through this photo set at work when my partner asked why there was a soap dish attached to the handlebars.

    In all honestly, its truly an elegant solution for that bag.

  • Besides the epic paint on this rig, that Columbus badge on the seat tube is just out of this world. I’m normally a pretty classic ‘black & chrome’ kind of guy, but this bike is just on another level, dope.

  • W. Bradford Williams

    I bought a rack this week for my all-road bike and it is not this rack and therefore I am sad. That is all.

  • Eric Hancock

    This bike is so good. So many well thought out details.

    I am curious about the cable-activated brakes. Did this predate good road hydro?

    • I think it’s more about reliability since Stan uses this as a touring bike too. Hydro can fuck up in the middle of nowhere, whereas cable is more reliable.

    • Hi Eric. When I got this bike almost 3 years ago the best option around was BB7 SLs (which are shit). I recently upgraded to these TRPs. Road hydro did not exist then, and the frame was built with cable-actuated disc brakes in mind. And besides, with the kind of traveling I do I prefer the simplicity and durability of cable discs.

      • Eric Hancock

        Makes perfect sense. Great stuff.

  • Justin Scoltock

    This bike is next level! And i’m totally biting that rack for my next bike!

  • Damien Milazzo

    Hey guys, does anyone have a link to the bag. I’m having trouble finding it, and it looks perfect for a daily commuter bag.


    • It’s made by a US company called Black Ember. It’s actually a DSLR waist pack that I modified. Great quality product.

      • Damien Milazzo

        Awesome, thanks Stan. That will fit a Surface perfectly, and I’ll still have room for lunch, clothes, etc. Now to make my own rack! And awesome bike, especially with the couplers. It’s so nice to just travel with your bike wherever you go.

        Cheers and Happy Trails!

  • Simon Weiss

    Can you share any information on the paint process? How was the paint mask to create that amazing patter? Looks like it was done by hand somehow. Would love to know more. Thanks