Hi, I took over a scooter. Derbi Boulevard 2T 50ccm I made a new candle in, air filter changed but I am at the end with my barely existing half-knowledge. It accelerates uphill only moderately, at approx. 25-30kmh the fun is over and much worse; it accelerates to approx. half-gas normal, if you continue to spin you think it sucks off, but recovers very slowly when you stay at full throttle. The spark plug looks brown if that is important. I do it to make it work as rational as it should? And what else do I imagine, or can it actually be that it is running much better on hot days than on cold ones? I hope I could express myself intelligibly enough. Alternatively – if there is someone from the Reutlingen area and the surrounding area who can / would like to report this.