Dahon Helios Folding Bike Loose Stem( bottom locking part)

[petko8680]

was just given a used, but in excellent condition dahon helios bike. Reason for giving it away is that the stem at the very bottom locking mechanism( the one circled in the picture) is loose, so it is turning left or right with just applying small effort, which makes it dangerous to safe as as on as I try to steer, only stem goes in the desired direction, but wheel is keep going straight. I think it is the bracket that has an allen bolt on it( the one you use to fold the stem), but problem is that I can tighten it all the way. There is still about a 1mm gap between the two parts of the bracket, so they don't join completely. I tried to tighten as much as possible, but it doesn't allow me to tighten it all the way. But when I tighten it as much as possible, you need to apply much more pressure in order to turn the stem. Which makes me think that that bracket is the problem. The allen bolt looks a bit short( not sure if that how is meant to be), because when tightened it doesn't go all the way to the end of the thread. So i am wondering if replacing it with a longer one will allow me to tighten the bracket all the way so that both ends can join. Cheers
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