- If you need clarification, ask it in the comment box above.
- Better answers use proper spelling and grammar.
- Provide details, support with references or personal experience.
Tell us some more! Your answer needs to include more details to help people.You can't post answers that contain an email address.Please enter a valid email address.The email address entered is already associated to an account.Login to postPlease use English characters only.
Tip: The max point reward for answering a question is 15.
Hi, Pete you may have squeaked your top end this is commonly known as "HEAT SEIZE" the piston heats up expands and becomes extremely tight in the cylinder bore and usually occurs mainly on 2 cycle engines right after a fresh top end rebuild, but it can also happen to brand new motorcycles, these are rare instances due to better quality control and education. Overheating failures that cause pistons to seize are many and each one should be carefully diagnosed to prevent future repeat offenders and the usual suspects are:
1. Lack of lubrication due to low or no oil.
2. Among the causes of lack of cylinder, lubrication is clogging of lubricator by dirt or waste, obstruction in oil pipes/lines, leaky check valves, leaky pump packing, broken oil pipe/line, oil too cold to feed.
3. Wrong type of oil used in premix or oil tank.
4. Improper premix ratio you should start with 32:1 as a baseline.
5. New rebuild piston to cylinder tolerances set up too tight.
6. Failure to follow proper break-in procedures with a 16:1 premix ratio.
7. Loose fasteners causing intake, base, or head gaskets to leak or blown crankshaft seal, failure caused by age, overheating or walking.
8. Holes in the intake manifold bent or warped intake flange or reed cage any stray air coming into a cylinder will cause a super lean condition.
9. Improper assembly of reed valve gaskets.
10. Insufficient warm-up time for temperature conditions before WOT.
11. Broken, pinched or cracked fuel line.
12. Carburetor fuel passages clogged or restricted from stale fuel varnish, ethanol sludge, dirt, rust, or fuel level in float bowl too low.
13. Main jet size too small or partially clogged
14. Air filter improperly installed, missing or not sealing.
15. Faulty or improperly adjusted oil pump and or cable.
16. Failure to bleed oil pump after a rebuild/replacement or running oil tank dry.
17. Engine coolant level too low, too old, or improper mixture ratio.
18. Radiator clogged, fins damaged, or faulty cap.
19. No liquid circulation due to failed oil or water pump.
20. Cavitation due to air in oil or coolant system.
21. Water and oil mix due to a blown head gasket.
22. Timing retarded due to faulty CKP sensor or CDI.
23. Improper spark plug heat range (too hot) and or gap.
24. Excessive engine load, brakes dragging, clutch slipping, transmission lubricant level too low or viscosity to high.
For more information about your issue and valuable "FREE" downloads that you will need for viewing or printing please click on the blue links below. Good luck and have a wonderful day. Kymco ZX50 SC10 motor build AF16 clone 49ccScoot com Scooter Forums 50cc KICKSTARTER PROBLEMS AND SOLUTIONS KYMCO ZX Service Manual Fever 1 50 ZX50 KCA SA10AL Kymco Scooter Parts Racing Planet USA KYMCO ZX 50 User Manual
Hi, not familiar with this bike,does it not have a separate oil tank,?, if your machine is pre mix this means you mix the correct amount of oil and fuel together as. Single form of lubrication, this way the oil gets directly to the engine parts, when the fuel,oil,and air mixture enter the engine the spark ignights it and the engine running process is started, the mixture is atomized to a form of mist, to much oil would render the mist to sticky, and seizure may occure from overheating, as would also be the case for to little oil, MY RESEARCH DOES NOT COME UP WITH A 4T 2 STROKE ONLY A 4 STROKE WHICH OBVOUSLY HAS NO OIL ADDED TO THE PETROL.