I use seafoam in all my bikes, UTV's, and ATV's as well as my vehicles.
Here is how I do it:
Once a yearn I pour 1/3 a can ( less on the bikes due to smaller engines) into a cup and remove a vacuum line that goes directly into the engine and let it sip it up at idle to get it into the cylinders and clean them. Then I shut it off after I gun it to stall the engine with one last gulp. ( takes two people )
Then I let it sit for 15-20 minutes so it soaks into the cylinders. When I start it there is a lot of smoke burning off. Then I drive it, preferably up to 60MPH for a few miles.
Then when I get back I put 1/3 directly into the engine oil (less on the bikes due to smaller oil capacity) the remaining 1/3 into my fuel tank. (less on the bikes due to smaller tanks)
Been doing this for many many years with zero issue.