WELCOME TO YOUR NEW ENGINE
Please note the following before use:
Oil Level – Most pit bike engines hold 700-750ml of oil. Please make sure the motor is level and flat when using the appropriate gauge. If using a dipstick, remove it, clean it, screw it back in all the way, and then remove it to check the oil level. When using a sight glass, the oil level must be approximately halfway up. We recommend Motul 5100 10W/40 from our shop.
Check valve clearance before first use – all 2-valve engines use the same valve clearance settings (engine cold) inlet = 0.08 mm and exhaust = 0.08 mm.
When using a DAYTONA 190 4V the settings are Inlet = 0.05mm and Exhaust = 0.07mm.
If you are unsure how to properly control your engine and adjust your valve clearance, please follow a YouTube tutorial.
We always recommend installation by a professional, qualified person.
Please ensure that the engine breather pipe is attached to the crankcase and the blind plug (if applicable) is removed. Make sure there are no kinks in the breather hose and check that you can feel the gases escaping when the engine is running.
We would always recommend using an oil cooler if possible. Using an oil cooler keeps the engine temperature below 190 degrees. Even though it is an air-cooled engine, it can get very hot in racing conditions. The cooler lowers the oil temperature, which extends the life of the components in the engine.
If you decide not to use a radiator, you will need to use a bypass pipe/hose to connect the oil passages. Otherwise, there will be a lack of oil at the top of the engine and major damage. This is crucial on ZS125 and ZS155 engines. DO NOT leave the blind screws installed.
We recommend that the engine first run through a few warm-up cycles before use. This involves starting the engine for about five minutes and then turning it off to allow it to cool completely. This will allow the piston to bed in and allow you to check the oil cooler lines for leaks.
We then recommend driving gently for about an hour (with breaks), not exceeding half throttle.
We would then finally advise you to change the oil and check the valve clearance and adjust it if necessary.
YCF offer a 30-day guarantee on motors. This only applies to manufacturing defects. User-caused problems such as incorrect installation, misuse, intentional damage and racing are not covered.
The 30 day period begins on the purchase date.
Regardless of whether you used the motor for 1 hour or 0 hours, it will expire at the end of the 30 days.
Racing Use – Please note that anything used in racing conditions will void the warranty as you will be subjecting the components to enormous stress.
These engines were never designed for competition use. Please consider this.
Items not covered:
Below are some examples of items that are not covered under warranty due to driver misuse.
Kickstart gears (caused by excessive pedaling and incorrect carburetor setup)
Clutch basket center gear (caused by excessive pedaling and incorrect carburetor adjustment)
Barrel and piston wear (dirty air filters, old or incorrect engine oil (transport oil)
Gearbox claws (caused by not using the clutch)
Premature valve damage (caused by overtightening)
Please use common sense when using these motors.