What causes carburetor to pop on Harley Davidson?

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.

Why is my CV carb not working on my Harley?

Again it should be emphasized, the #1 cause of carburetor related problems on a Harley or other V-Twin motorcycle is VACUUM LEAKS. The CV carb is dependent upon vacuum to function properly. 2) Check that the Needle Jet (nozzle) is installed correctly.

How to reset the odometer on a Sportster?

Push odometer reset button in & hold. Turn ignition switch to Ignition and release odometer reset button. Background lighting sould illuminate, speedometer needle should sweep its full range and indicator lamps (battery, security, low fuel, check engine and cruise) should illuminate.

What should I do if my Sportster has a problem?

Turn Ignition switch to OFF & Run/Stop switch is to Run. Push odometer reset button in & hold. Turn ignition switch to Ignition and release odometer reset button. Background lighting sould illuminate, speedometer needle should sweep its full range and indicator lamps (battery, security, low fuel, check engine and cruise) should illuminate.

What makes the carburetor pop on a Harley Davidson?

One of the most common problems that customers complain about is the spit-cough-pop from the carburetor as a Harley goes from idle to ¼ throttle. This can occur on any model, any carburetor, but seems to happen most often with the stock CV Keihin carburetors used on the newer (90 up) Big Twins and Sportster models.

Again it should be emphasized, the #1 cause of carburetor related problems on a Harley or other V-Twin motorcycle is VACUUM LEAKS. The CV carb is dependent upon vacuum to function properly. 2) Check that the Needle Jet (nozzle) is installed correctly.

Can a CV Keihin carburetor cause a Harley to stall?

This can occur on any model, any carburetor, but seems to happen most often with the stock CV Keihin carburetors used on the newer (90 up) Big Twins and Sportster models. This condition is not only annoying, but can cause the Harley to stall dangerously at stoplights, and can damage intake seals.

What causes a coughing sound on a Harley Davidson?

I thought I’d pass along my findings: One of the most common problems that customers complain about is the spit-cough-pop from the carburetor as a Harley goes from idle to ¼ throttle.

What causes CV carburetor to wear and crack?

Check that fuel sprays from the accelerator pump nozzle when rolling on the throttle (test with engine off). The accelerator pump diaphragm will wear or crack over time or if left to sit in a fuel filled CV carburetor for extended periods and will eventually deteriorate. 5) Pinched or cracked slide diaphragm.

What kind of idle mixture does a Harley Davidson use?

I went to the 48 idle jet and raised the needle 1 washer and am running a 195 main with 95″ and cams and exhaust. Getting 40 mpg and have the idle mixture turned out 3 turns. It runs good and NO coughs at any rpm and no rich smell at the pipe at idle. The further out you turn out the idle mixture the leaner it gets.

What causes idle surges on a car ECM?

Idle surging can be caused due to other issues in the car, but if it happens in conjunction with other throttle position sensor symptoms, the culprit is often the TPS. At idle, the ECM will not get the correct information and the throttle will variate randomly causing idle surges.

Why does your motorcycle only run on choke?

Fuel goes bad after time, and the first circuit/jet to clog with varnished up fuel is the pilot jet. This circuit delivers fuel for idle, and has the smallest passages found in carburetors.

Why does my bike lose power when I idle?

Again, if you ride a modern bike you’ll have no idea what a choke is, but even Electronically Fuel Injected motorcycles reveal a lot by “blipping” the throttle. Rich bikes are getting too much gas, so they idle high but lose power when given initial throttle because they can’t burn all the gas.

Do you need to tune the fuel mixture on a motorcycle?

Once you have the motorcycle up and running, you will need to tune the idle mixture. Every carburetor is equipped with an AIR or FUEL screw to tune the air fuel mixture at idle.

How can you tell if your bike throttle cable is going bad?

The throttle cable normally lets you know it’s going bad by refusing to snap back the throttle grip when it is turned and released. Never ride such a bike – they call that a “suicide throttle” for a reason.

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