26,dont like the 29 er......still in love whit the 26,i put a set off crank bros egg beater titanium version,hard to belive but the scale bounce betwen 19.5 20 pounds,my wife got the spark in aluminium,24 pound,mine is lighter shes jalous! this bike as been costomized by the ownwer of the store where i buy it .it use the be is bike for racing,but he decide to sell it,i got it for a rediculous price,have no choice to take it......gonna start some small race this season,for fun