best write up I have found on the web so far Most likely when they have a stumble when shifting to a higher gear its a indication of trash in the carb. or needing a carb. rebuild. Over the yrs. I have had a number of Suzuki's that had a stumble problem. After going through everything, plugs, fuel filter fuel pump ect. all it needed was a carb. rebuild. If it has a small stumble most of the time sea foam will clean it up after several treatments. I'd go with the rebuild kit if that doesnt work. It appears you have done everything else . Rebuilding the carb. is not as bad as you would think. 1) get some adult beverage 2) take pictures and tag vacuum lines 3) get one of your significant others white towel 4) remove carb. 5) take a beverage break 6) break down carb. laying out parts in order(dont mess with adjustsments) 7) place parts in carb. cleaner and clean(make sure jets are open) 8) take another beverage break 9) put carb. back together 10) install on manifold 11) take another beverage break 12) hook up vacuum lines 13) take two beverage breaks 14) turn ignition on Oh and make sure you install the new parts somewhere a long the way. I don't think you really need a mini for this one
vacuum leaks are 85% of carb and idling problems, use a vacuum gauge or carb cleaner, carb cleaner will send the engine to high idle if you have a vacuum leak, make sure the vacuum port in the air cleaner canister is working properly, also check that your vacuum advance hose isn’t cracked coming off the distributor to the vacuum manifold tree. The vacuum manifold tree is brass on the bottom to go in to the block and plastic on top. Plastic wears out with time and will break or leak, which causes a vacuum leak. Some manifold vacuum trees are 3 or 4 port, make sure to replace it with a new one. When I buy parts I buy 3 at a time that way I have them on hand or in case they can’t get them any more. The vacuum manifold tree is located behind the carb. If you looking at the carb from the right side of the bed, it will be to your 1 O’clock tucked down inside. Remember to use a marker or different colored tape to mark the vacuum lines so you know where everything goes back too! Good luck!’ A case of super iced down cold beverages!!’
