Bike porn

Lovin this in spite of the seatpost.

Bit confused by this. 360 drops, low standover and maguras made me think street/trials bike but Thomson layback, chainring/guard and bolt on fixed gear suggest not. Also don't understand the roller/chain tensioner thing. Surely it can't be spring loaded if it's being run fixed? Maybe adjustable somehow?

Im probably reposting, but many modern trials bikes have a fixed sprocket on the wheel and a freewheel built into the chainset.