It does sound like a tire problem or a balance problem. I would take the wheel off and take it to a motorcycle shop and have them check the balance. You tried Ride-On, which I use myself and have been very pleased with. If it checks out to be out of round or off balance, then you know what to do after that. Either they can balance it and all will be fine or you need a new tire most likely. Try a Shinko 244 Golden Boy for a better front tire and use the Ride-On again. Please keep us posted. I don't think it is the springs and with your weight, they are probably fine and don't need to be changed.
*if there are balance weights now on the bike's front tire, take them all off and see if the Ride-On will do it's job. Otherwise, yank the tire and rim off and take it to the shop to be checked out.