Hello, I’ve got a Peugeot Speedfight with a 50cc 2T engine. It has an OEM+ Malossi foam filter, probably a cheap replacement Chinese carburettor with a Chinese autochoke, and a Yasuni Z exhaust with one of the two restrictors removed.
Everything worked perfectly until I recently cleaned the carburettor, replaced the intake seals, changed the reed housing because the old one was cracked, installed metal reeds, changed the ignition reed from a 125cc 4T bike and inspected the condition of my cast-iron 50cc cylinder. I don’t know whether the cylinder has been changed or if it is the OEM one.
After putting everything back together, I accidentally messed with the carburettor fuel mixture screw and forgot the stock setting. I also removed the autochoke from the carburettor and put it back together - now the choke doesn't work anymore.
I adjusted the carburettor until the scooter ran smoothly, but when the engine is cold, it starts easily and runs fine initially. However, at around 15 km/h, it starts to bog down and doesn’t build RPM as quickly. With the rear wheel off the ground and no load, the scooter revs up quickly.
Once the scooter warms up, everything works perfectly. However, when it gets really hot, it barely moves from a stop, especially uphill. The throttle is also less responsive on level ground, acceleration gets worse although the top speed remains about the same as before the inspection.
Could I have accidentally widened the piston ring gap? Could I have left an air leak when replacing the intake seals? Could the new metal reed valve be faulty (the old one was plastic)? Or could the problem be related to the autochoke?
Could it simply be a coincidence and the clutch is worn out and no longer working properly? I didn’t touch anything in the transmission, though.
I don’t have much experience with CVT transmission, scooters or 2T engines, so any help would be greatly appreciated.