Hi I am asking if anyone can help me with my dt125lc mk2 year sept 1985 frame stats 35A. I replaced my exhaust system yesterday I put a good fresco expansion chamber on and I took my old silencer off and put an original silencer from a mk3 dt125lc and I lost power dramatically. As we know the powervalve on the dt125lc's kicks in at around 6,000 Rpm. Since I changed my exhaust system, when I am out on the open road I can't get up to 6,000Rpm if I knock it down a gear the revs just die away so I can't take it for a blast to blow the cobwebs out the exhaust system. I've replaced the spark plug checked the bowl under the fuel tap and cleaned it but it don't feel like a fuel problem, it feels more like the clutch is slipping but the revs die away also whilst in drive plodding along like a step through scooter. I know it's not the clutch I am hoping it's the silencer, I really don't want to put my old exhaust system back on as this fresco exhaust is in mint condition but bought second hand off e-bay. I need to ask if anyone knows the answer to this problem. Once I park my DT up for the night lock it and turn the petrol off, I go back to it the following morning and as soon as I take the bike off the side stand petrol flows out at a good rate from an overflow pipe at the bottom of the carb does anyone know what causes this. If any one can help I will well appreciate it. I have only had 3 yamaha's in my time and not for very long. I spent a lot of my time around my first bike being a suzuki ts100erz which is an aircooled suzuki scrambler and ever since I have been around suzuki aircooled bikes this is my first watercooled bike with a YPVS system on it. Thank you Blake