2001 Honda Shadow ACE 750 idles, but won't rev up

Maybe it could be a bad plug or plug wire,coil pak,burnt valve

The shadows have an issue with the gunk getting built up in the carbs. I would take them off get a carb cleaning product and spray the living heck out of it making sure you get into all the ports and everything. This seems just like a carb issue and nothing else

You are correct about carb dissembling & cleaning bare min drop bowels & carb clean the jets idle & main any adj screws remove & spray out passages. count the turns so to replace screws to same place.. biker bandit may have some dias...

Clean and inspect the carb diaphragms when you have the carbs apart to clean them. Concentrate on the slow jets and the passage ways behind the slow jets.

easy fix. take your carbs off and rebuild them. at the very least clean out the jet screws. a carb rebuild would be best and most effective. make sure to change the feul filter as well. whenever one micron of anything gets into those things they just stop working. have fun and remember to disconnect the battery befor starting any big repair.

You need a long reach plug wrench tool should have one in your bikes tool kit .

It sounds like you may have or will be jetting your carbs. I did this using the directions with the kit and used the Clyman manual for this bike to show me step by step how to remove the carborator. You will only need to attach 2 of the 4 hoses on your carb. syncronizer. If I remember right, you need to remove the bolt-on cooling fins to expose the engine block. The is a black screw or bolt that you take out and screw the threaded metal adapter of the sync tool. Be careful using the sync tool. Be very light on the throttle or the vacuum in the cylinder will **** in the mercury from the sync tool - not good. The problem you are stating on idle & backing off sometimes happens when the carbs are running rich (too much fuel) Hope that gets you in the right direction.

carb needs to be cleaned