Before your hot lap, and after it, you need a seat post extender for your warm up and cool down. The Tangent Seat Post Extender is available in 26.8mm and 27.2mm diameters and comes with a seat clamp included so when you whip out your race seat, you can slot the extender in and bang your race seat back in and you're good to go. Or permanently set up your extension post with a seat and shave seconds off your changeover time. 

Specs:

Length - 400mm