My 2009 Evo 300 generally starts and runs OK but under hard acceleration it sort of surges unevenly and sometimes bogs a little on hard or even mild throttle application. This surge/bog continues thru increasing revs at full throttle.

I'm not SURE but it seems like adding some choke may help but not cure these problems a little?

I'm guessing this means either:

- There is crap in the carb?

- AND/OR The jetting is too lean for cold weather?

Plan is to take carb apart to clean it and find out what the jetting is.

Is there something else I should be doing different or beyond the above?

Does anyone have jetting recommendations? I don't know where in the documentation to find this info?

THANKS! for any help.

No experience with the Beta 4t but surging on a 4t is generally related to a lean condition. First thing I would try is raising the needle and possible a richer pilot.

Have you had the carb appart earlier?.... If so you may have the CV bellows boot pinched as they are a SOB to put together properly.

As above, raise the needle all the way( lower the clip to the bottom groove) to get a stronger richer midrange