Cannondale 300m handlebars turn if you hold the tire
Hi, sorry for the confusing title but I was recently given an old 300m. It's in good shape but I was just going over everything and Checking it over and found the handlebars will turn even if you're holding the front wheel in place.
I've tightened the bolt that goes down into the stem as tight as it will go but the handlebars can still be turned while holding the wheel. They aren't extremely loose but it's enough to make me wary of riding it obviously.
Any help would be greatly appreciated.