How does carb effect throttle positions on a motorcycle?
Motorcycle carbs have a few circuits that effect different throttle positions. Pilot Circuit – small effect on idle. Higher effect at lower RPM’s with decreasing effect to full throttle Main Jet – Wide open. Fuel is metered through the main by the jet needle at different throttle positions.
When to bottom the A / F screw out on a Harley Davidson?
The A/F screw is for idle and transition from idle to pilot/slow circuit. Depending on the motor configuration, exhaust, etc., that screw should be somewhere about 3 turns out, give or take. There is no fixed number of turns, every motor is different. When you bottom the A/F screw out, the motor should idle rough, stumble and ususally will die.
What causes lean or rich carb settings on a motorcycle?
Rich conditions can be created by people too but the condition is usually caused by: 1 Installing a jet that is too large. 2 Setting a float level that is too high. 3 A Choke that is stuck or not turned off. Ensuring proper cable routing so… 4 A stuck float in the float bowl will allow fuel to overfill and then spill out the main jet into…
Can a stuck petcock cause a motorcycle to hydrolock?
A stuck float with a standard petcock can create issues as the fuel will do what is stated above but when the bike is sitting. This fuel can also fill the cylinder and create hydrolock and destroy your engine when you start it. The piston cannot get to top dead center on the compression stroke and it bends your connecting rod. This is real.
How do you fix a carburetor on a Harley Davidson?
Secure the carb in either a vise or by other means that will allow the carburetor to remain steady. Drill a hole into the plug making sure not to “punch” through too fast. You don’t want to damaged the mixture screw just below the plug. Allow the drill to slowly cut into the plug rather than push.
What kind of carburetor does a Harley Davidson use?
This simple procedure is a great Harley tech tip that applies to all Harley carbs from 1989 to present that use the CV style Harley Davidson carburetor. Earlier models equipped with the older butterfly style carbs (pre-89 Evo’s, Shovelheads, Pans, and Ironheads) are excellent candidates…
Where is the mixture screw on a Harley CV carburetor?
The CV style Harley carburetor has a small cylindrical tower protruding from the bottom rear of the spigot (behind the bowl). The tower is plugged with a soft metal insert covering the mixture screw. Gaining access to this screw is key to fine tuning and must be remove.
How is the choke cable attached to the carburetor?
The choke cable can stay attached to the carburetor during this procedure, simply detach the knob end from the horm bracket. Disconnect the fuel line from the fuel inlet on the carburetor or the opposite end connected to the fuel petcock, whichever is simpler to access. The hose is likely fastened using a special crimped clamp.