A steel gravel bike designed to take you as far as you can imagine, the Sour Purple Pie is built around a smartly-designed Pinion bridge that both neatly tucks in the electronics of the Smart-Shift gearbox, but also makes room for proper mountain bike tires to find grip, comfort, and control far off the beaten track. Handmade in Germany, Sour builds this new adventure bike in small batches, and frame kits only, letting each adventurer build it up to their heart's content.
I'm gonna start this off by saying this bike looks freaking awesome. It really stands out from the crowd of similar-looking carbon and aluminum bikes with oversized tubes and familiar suspension designs. I don't want to overstate it, but like many handmade bikes, it's more like a functional piece of art than any mass-produced bike could ever hope to be.
Support us! Bikerumor may earn a small commission from affiliate links in this article. Learn More Esker Cycles has a sweet new rigid steel, singlespeed-friendly bike for the discerning mountain biker looking to blend classic klunker looks with modern trail-ready geometry, plus all the good new standards. But it is seriously limited, so if this looks like your kind of ride you should probably put your chips on the table fast before they are gone.