Re: suzuki dt 75 ouboard bogs down when given throttle
I hope you sprayed gas/oil mix and not just gas into the carbs. If that engine is running lean, not only is it not getting enough gas, but it's not getting enough oil. Spraying just gas in the carbs will delute what little oil it's getting, which will damage that engine. If you are going to spray anything in the carb use a 50:1 gas/oil mix.
As far as your problem goes, it could be a number of things. Gas tank my not be venting...could have a bad primer bulb...could have a fuel restriction somewhere...may be a link n sink issue.
Do you have a good flow of fuel from tank to motor?
Have you replaced the primer bulb?
When was the last time you had the carbs rebuilt?
Have you checked compression?
Have you checked or replaced fuel filter(s)?
Have you checked spark?
When was the last time you replaced spark plugs?