I found a technical data sheet of some sort. It said that the front fork should have 50mm. of spring movement. That is to say it should move up and down about 5 cm. It also said that Puch uses hydraulic suspension dampers of some kind. I don't know that yours has these though. I think something is either unattached or broken somewhere in the tube.You can get a good manual and parts at www.themopedjunkyard.com. I found them at www.moped.org.