I recently bought a replacement contra spring for my LX50, I was finding it increasingly difficult getting up steep hills and accelerating after slowing down for roundabouts etc. So I decided on a two pack of Naraku springs. A 1000 rpm and a 1500 rpm to see which one worked best for me. Replacing the Spring was straight forward enough once I bought the right tools for the job. When I ran the scooter for the first time the pull off was extremely smooth and the gearing seemed to have improved. However after I took it on a longer high speed run I found that the pull off was terrible, dangerous in fact. I could barely get the thing moving and at idle there was an awful slapping sound coming from inside the transmission cover. I got it back home and took a look inside the cover, the pulley was stuck in a half open position and it was the slack belt making the slapping noise. I decided to stick the old spring back in and on comparing the new and old springs I noticed that the new one was wound in the opposite direction to the old. So when the pulley plates were opening (and as they rotate slightly when doing so) it was compressing the in the wrong direction, opening the spring instead of closing it. The spring must have dug in slightly stopping the pulley from closing. Clearly these springs are not fit for purpose. Has anyone else ever had a problem like this before?