I had this with our new Zinger. One arm would suddenly come down. I found that if you wiggle the arm a bit when the pin is trying to go into the hole, then you can feel it go all the way through the metal to the inside of the arm and then no problems. it is imperative that the handle be pushed all the way in toward the arm when done, though! It's easy to leave it kind of not quite pushed in. i think those new arms, while nice and light, are a crummy design compared to the ones I had on my Sunline.
Charlie
__________________
Charlie
|