It depends on many things.
* Pulsar 150 DTSI - 50-60 Km/l (Depending on the driving skillls, the condition of the bike & the traffic)
* Pulsar 150 Simple - 40-50 KM/l (Depending on the driving skillls, the condition of the bike & the traffic)
The above two cases are generalized form. Now if you talk personal my Bajaj Pulsar 150 DTSI runs for 60-65 KM/L in normal traffic conditions. When I go for a long ride (highway) it delivers a mileage of upto 65-70 KM/L.
This I achieved just due to regular servicing of the bike. The performance in terms of mileage can also be increased by following methods -
* Use Power Petrol
* Minimal use of Brakes
* Minimal use of Clutch
* Minimal shifting of gears
* Driving in normal speed range (40 -60 KM/Hr)
* Maintaining the condition of the bike (Servicing it regularly will sure help)
I hope this satisfies you.