Motorcycle Repair: Fuel trouble?, exhaust pipe, revs

Question
Hi i was just hoping you could help me out here. My bike idles awesome revs up awesome in neutral but then you drive it and try to open up the throttle and from about 1/4 throttle to wide open it jerks bad like it hesitates i dont know i did make sure the carbs were right clean it looks like its getting fuel too any ideas?

Answer
If the carbs are clean and the bike revs OK when in neutral, but bogs down under power, check that some critter hasn't made a nest in your exhaust pipe or check for another exhaust blockage.  Otherwise check the ignition timing and make sure the fuel is fresh...  Let me know how you get on,  Jan