engine problem

I,M HAVING PROBLEM with my px 125 .in 3rd and 4th gear i,m loosing power ,as soon as i go down into 2nd gear it starts to go fine.i,ve changed clutch plates.my oil was smelling of oil so i,ve changed clutch and drive oil seals replaced t lead and clutch cable

You havn’t put anything to block the air breather, under the seat?
also check the petrol cap breather(try riding it with out cap )

[:look:] got problem sorted had to replace carb[:look:]

  1. check carb (If you have gas filter - change)
  2. main jet (maybe is dirty)
  3. check tank (Fuel tap, packing fuel tap)
  4. maybe fuel hose is breakdown

Good luck
i don’t like like that problems

how’s your compression? if the engines old or worn due to lack of lube it’ll loose power and struggle with longer gears.

hello,

It seams your engine needs to go higher in rev to get some useful power. So if your oil seal are fine, check out the piston rings and ignition timing.

everything else on bike is fine its just when i,m in third and fourth gear its acting as if my carb was dirty but if i engage the clutch lever then release it full power is restored

soz for taking so long.i put in new rings and checked timing still no joy.as i meant to say above my oil was smelling of petrol so thats why i changed the seals,and put in new clutch ,spark plug,t lead and cleaned the carb three times.any other ideas .i,m going to barrow a carb itself and see[:@]