Dirt jumping has ben the last bastion of the 26" wheel ever since the hoops wars kicked off but if one builder from the Czech Republic has his way then it may not be the case for much longer.
You may remember the Switchcraft name from a Brit-inspired 29er steel trail bike
we featured in 2020. Since then, Jakub has added a flat bar gravel bike, a second single pivot and this radical hardtail to his line up.
For now, this bike is simply an experiment without a name as Jakub wanted to see how short you could physically make the chainstays on a 29er and how that would affect the handling. The answer is, apparently, 388mm. Given that the radius of a 29" wheel is 368mm and you have to fit a tire in there as well, it's safe to say he's cutting it fine.
Jakub has achieved this by welding the seat tube to the downtube with a 60mm offset from the BB and another smaller tube used as a reinforcement. There are also chainstay yokes, which means there are steel plates welded to BB to fit chainring properly. With the set up he has been running, Jakub says you could fit a credit card in the clearance between the wheel and the seat tube, but that's about it - you certainly don't want to take this bike off road unless the dirt is packed hard like concrete.
Jakub's unorthodox tube layout has allowed for the 388mm chainstays.
For now, Jakub says he is running the bike as an oversized BMX and that the short stays mean he has no trouble at skateparks or just street jibing. He says the main difference from a 26" dirt jumper is the stability. offered by the momentum of the big wheels when jumping.
The frame weight is 2,3kg and the whole bike is 12kg. He has no plans to commercialise the frame but could build more up as one-off projects if there are requests.