What kind of carburetor does a 1989 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 for upgrading to a modern Harley carburetor.
What causes carburetor to pop on Harley Davidson?
The gaskets between the head pipes and the exhaust ports of the heads is a crush fit that will leak if the pipes are removed, reinstalled, or over/under torqued. Cool air drawn into the exhaust at these seals will result in hesitation or popping commonly misdiagnosed as a carburetor problem.
Can you knock off a Harley Davidson carburetor?
There is no guarantee that any part (original or CVP) will fit those knock-off carburetors. If your CV carb does not have the name Harley Davidson cast above the bowl on each side it is a knock-off. The carburetor atomizes gas in proper proportions to the air pulled in through the air intake.
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.
Can a Harley Davidson CARB be pulled away from the manifold?
A simple “Top” and “Bottom” should suffice when tagging each cable. Now that you have enough slack in the cables you can pull the carburetor away from the manifold. A Harley carb is only held to the manifold with a slip fit rubber manifold boot.
Is it possible to tune a Harley Davidson carburetor?
Tuning your Harley Davidson carburetor is simpler than most think and can be performed with a few common tools. 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.
How do you remove the CARB from a Harley Davidson engine?
Now that you have enough slack in the cables you can pull the carburetor away from the manifold. A Harley carb is only held to the manifold with a slip fit rubber manifold boot. Gently rock or twist the carb back and forth as you pull it away from the engine. Remove the cables that you tagged and remove any vacuum hoses.
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 for upgrading to a modern Harley carburetor.
A simple “Top” and “Bottom” should suffice when tagging each cable. Now that you have enough slack in the cables you can pull the carburetor away from the manifold. A Harley carb is only held to the manifold with a slip fit rubber manifold boot.
When to tune a Harley Davidson CV carburetor?
These tuning steps apply to all Harley CV carbs from 1989 to present that use the CV 40mm style Harley Davidson carburetor but also apply to the CVK40 found on other models. Always start with a fresh set of spark plugs when tuning. The carburetor will need to be removed from the manifold so refer to your factory shop manual for this procedure.
How do you change carburetor mixture on Harley Davidson?
Pry the plug out using a pick or awl. You can also thread a sheet metal screw into the drilled hole and use this to pull the plug out. Now that the plug is removed clean the area around the mixture screw so no metal fragments remain. At this point there are two methods for adjusting the mixture.
What kind of carburetor does a Harley Keihin use?
Modifications to this reliable carb continue today in the form of race tuner kits, hybrid slides, and Stage 1 Kits . Due to the CV carburetor’s stable metering characteristics, Harley then commissioned their own version to replace the aging butterfly style carburetors.
When did Harley Davidson start using CV carburetor?
Harley Davidson started equipping models with the CV carburetor in 1989 and has utilized the same carb ever since. A CV carburetor (Constant Velocity) incorporates a vacuum operated slide that varies the venturi size within the carburetor, thus maintaining a constant velocity.
How is the CARB held to the manifold on a Harley?
A Harley carb is only held to the manifold with a slip fit rubber manifold boot. Gently rock or twist the carb back and forth as you pull it away from the engine. Remove the cables that you tagged and remove any vacuum hoses. If your model has multiple vacuum hoses it would be a good idea to label these as well.
How many turns does a carburetor need in a Harley Davidson?
If the engine responds quickly with a smooth blast and no backfiring through the carburetor, you have your idle mixture right. If backfiring occurs through the carburetor then adjust the idle mixture screw out another 1/8 turn. Normally, the mixture screw should only require 2 to 3 turns.
When to change the idle mixture on a carb?
•If idle mixture screw is more than 1 3/4 out after idle mixture is correctly adjusted, it is a fairly good indication that the intermediate jet may be too small and should be changed to the next larger size. Conversely, if the idle mixture screw is less than 1 1/4 turns out the intermediate jet may need to be changed to the next smaller size.
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.
What is the idle mixture screw on a carb?
Idle mixture screw, 11/4 turns from lightly seated. Idle speed screw, ½ turn clockwise from engagement point. Accelerator adjustment screw, two turns counter-clockwise from seated. Start bike, bring to operating temperature. Set idle speed adjusting screw, clockwise to increase rpm, counter-clockwise to decrease rpm.
What should the idle speed be on a carb?
Start bike, bring to operating temperature. Set idle speed adjusting screw, clockwise to increase rpm, counter-clockwise to decrease rpm. Idle rpm range should be 950 to 1050 rpms. Adjust idle mixture by turning idle mixture screw slowly clockwise until the engine runs poorly. Note position.
What to do when carb runs super rich at idle?
Chris, start with the carb at 1/2 turn open from closed throttle for the speed screw, 1 – 1.25 turns open on the mixture screws. Your engine was running with too much throttle, you need to close it down.
If the engine responds quickly with a smooth blast and no backfiring through the carburetor, you have your idle mixture right. If backfiring occurs through the carburetor then adjust the idle mixture screw out another 1/8 turn. Normally, the mixture screw should only require 2 to 3 turns.
What causes black smoke from a Harley Davidson carburetor?
If you experience any coughing through the carburetor, adjust the mixture out another 1/8 of a turn. Black smoke seen from the exhaust at idle or a feeling of sluggishness off idle indicates you may have set the mixture too rich. If your bike is now idling steady and responds well from a start then you are all set.
How can you tell if a Harley Davidson carburetor is right?
Blip the throttle a couple of times and observe the results. If the engine responds quickly with a smooth blast and no backfiring through the carburetor, you have your idle mixture right. If backfiring occurs through the carburetor then adjust the idle mixture screw out another 1/8 turn.
If you experience any coughing through the carburetor, adjust the mixture out another 1/8 of a turn. Black smoke seen from the exhaust at idle or a feeling of sluggishness off idle indicates you may have set the mixture too rich. If your bike is now idling steady and responds well from a start then you are all set.
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.
Why is my Harley CV carburetor stalling after tuning?
Hesitation or stalling can sometimes occur after tuning or rebuilding your Harley CV carburetor or if your Harley carb has not been maintained. The following are common issues sometimes encountered after tuning or rebuilding a Harley CV carburetor.