These are pretty easy to replace and a must if you want to upgrade your engine's performance with performance parts or upgrades. This is a Carburetor Pilot Idle Jet #40 for the CN250 CF250 GY6 250 172MM engine. This is a Carburetor Idle Jet #36 for the CN250 CF250 GY6 250 172MM engine. This is a Carburetor Idle Jet #35 for the CN250 CF250 GY6 250 172MM engine. If you don't your engine can sieze on you. If it is 50 degrees colder you would increase your jet size at least one step up. When the air is colder it requires bigger jets because cold air is more dense. You will want to go down one (1) jet size for every 1750' to 2000' you go up in elevation. At 4000' feet you will have lost about 12% of your power output. You will loose about 3% in power for every 1000' in elevation. When you are dealing with elevation you will want to rejet to prevent your engine from siezing and requiring a rebuild.
#X moto 250ccm install
If you upgrade beyond small adjustments you will want to install a Performance Exhaust to handle the increased combustion and minimize back flow issues.Īltitude can play an issue in scooter performance. For smaller upgrades replace the stock air filter with a Performance Air Filter for this engine. Mechanics Note: If you increase the size of your stock carb jet you will want to improve your air flow both in and out of the engine. This is a Carburetor Idle Jet #34 for the CN250 CF250 GY6 250 172MM engine.