How do I check spark plugs?

Check coils,module,wires,any codes?

By stuttering I assume you mean misfiring...

Fuel starvation could cause stuttering but mostly insufficient spark is the cause.

Cylinder pressure rises during acceleration making the atmosphere around the spark plug very dense so the spark needs to work harder to jump the gap. If the spark plug is worn or the gap is too wide or if there is insufficient reserve power available the spark will fail to jump the gap.

you have changed everything so it should go unless you haven't checked the fuel pressure and injectors of problems in the carby if you have one as not all faults you describe are in the electrical system

Check the air filter!
Make sure the noise is coming from the engine, not the trans (is the noise also appearing when you rev it up in Park?)!
Is it the 6 or 4 cylinder engine?
How old are the spark plugs and cables? Take the distributor cap off and check for the finger having a good contact. Maybe it's worn out?
Check the fuel and fuel line. Is the stuttering appearing since you refueled? Maybe you got bad fuel...
Last but not least exchange the fuel filter (or have it exchanged by a shop). Autozone.com has some pretty good how-to manuals about all this.

First look at the spark plugs and ignition wires especially if it has over 60K miles. Secondly it could be fuel related like dirty injectors or poor gas. If it happened suddenly, you might have gotten water in the gas; try removing the fuel filter and dumping the fuel in the filter reverse flow into a clear glass jar and see what you picked up with your gas; then replace the filter.

Could be a transmission problem or something as simple as bad spark plugs.
The engine is under the most load when RPM is low and you are trying to accelerate, such as when it upshifts.
You should have the computer checked for trouble codes and hopefully that will point you in the right direction to test.
If the spark plugs have more than 50,000 miles of wear you might start with replacing them.

i would check the spark plug wires since it will misfire when it is raining if they are bad.

The Softail series of H-D motorcycles are heavy machines. Much heavier than the Dyna series bike. Due to this, their acceleration is on the sluggish side. There are two things you can do. You can either do some performance modifications on your engine or you can change the final gearing on your bike. Since this post is saying that this is a 2001 model bike, it leads me to think that you are not the original owner of the bike. If this is the case, check the final gearing on the bike as a previous owner may have changed the gearing to lower the RPM's of the engine at highway speeds. It should have a 31 tooth front pulley and a 70 tooth rear pulley. A lot of owners change the final gearing to "international" gearing to lower the engine speeds. They'll change to a 65 tooth rear pulley. This requires that the belt be changed as well. Some change the front pulley to a 32 tooth to do the same thing. This will cause the bike to feel sluggish on acceleration. The only other thing that would cause the bike to be sluggish is the carburetor could be jetted too rich if the engine is equipped with a carb.

try changing spark plugs and fuel filter. if that dont work do a compression test on it.

Try changing out your distributer cap and rotor button. Let me know if that solves your problem.


Thx