Things you may not know.
1 - An engine will run richer in taller gears. This is due to the acceleration rate being slower & allowing more time for the carburetor to deliver fuel. Fuel flow always lags behind air flow as fuel is heavier.
2 - The longer you hold the throttle open the richer the jetting. Same reason as above.
3 - If you snap the throttle open & the engine doesn't respond - 90% time it's lean. Same reason as above.
4 - CV Carbs deliver fuel in response primarily to rpm, a piston slide carburetor responds to throttle percentage opening.
5 - When your jetting is correct a carburetor will work good in a surprising large range of air temperatures and humidity. If it doesn't then your jetting is on the fringe of the optimum setting.
6 - Slightly lean and your engine response and performance will be poor, slightly rich and you will likely not notice a problem. This is why most jet kits are setup on the rich side of optimum to avoid customer complaints.
7 - Airbox modifications or removal will have the biggest impact on jetting.
8 - On a CV Carb, you do not control the rate of acceleration....that is set by the size, number of vacuum slide lift holes and stiffness (rate) of the slide lift spring.
1 - An engine will run richer in taller gears. This is due to the acceleration rate being slower & allowing more time for the carburetor to deliver fuel. Fuel flow always lags behind air flow as fuel is heavier.
2 - The longer you hold the throttle open the richer the jetting. Same reason as above.
3 - If you snap the throttle open & the engine doesn't respond - 90% time it's lean. Same reason as above.
4 - CV Carbs deliver fuel in response primarily to rpm, a piston slide carburetor responds to throttle percentage opening.
5 - When your jetting is correct a carburetor will work good in a surprising large range of air temperatures and humidity. If it doesn't then your jetting is on the fringe of the optimum setting.
6 - Slightly lean and your engine response and performance will be poor, slightly rich and you will likely not notice a problem. This is why most jet kits are setup on the rich side of optimum to avoid customer complaints.
7 - Airbox modifications or removal will have the biggest impact on jetting.
8 - On a CV Carb, you do not control the rate of acceleration....that is set by the size, number of vacuum slide lift holes and stiffness (rate) of the slide lift spring.
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