125z will win..coz 125z is 2 stroke while 135lc is 4 stroke..even 135lc got higher cubic capacity,the engine system is different.. 2 stroke engine will complete the process(intake,compression,combustion and exhaust) in 1 cycle only but 4 store need 2 cycle to complete it..by theory, 2 stroke is 2 times more powerful than 4 stroke..but actually its not exactly 2,its about 1.6-1.8..