Question about 2003 Harley Davidson XL 1200 C Sportster Custom

1 Answer

Hard start or no start when hot.

Acts like it is out of time, back fires, also main lead to voltage regulator becomes hot at connector. 2003 xlc 1200 with screaming eagle 7500rpm module

Posted by on


1 Answer

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points


    An expert that got 10 achievements.


    An expert that got 5 achievements.

    Brigadier General:

    An expert that has over 10,000 points.

  • Master
  • 4,565 Answers

Your choice of words is a bit confusing. "Backfire" is used in several different ways. It could mean that it's spitting back out of the carb or popping out the exhaust. But, let's try this.

Most of time when I hear complaints like this, the engine is spitting back through the carb. This is the most common problem and it's caused by one thing, the carb is running lean.

Now, the bikes come jetted very lean from the factory so that they meet EPA emissions standards. The way I usually fix this problem is to go up one size on the slow jet. The factory slow speed jet is usually a #42, and I install a #45. I also take the slide out so I can get to the needle. I lift the needle out of the slide and install a 3mm flat washer. A 3mm flat washer (flat washer for use on a 3mm bolt or screw) is about 0.023" thick. Install it by sliding in on the needle from the long end of the needle and then put the needle back in the slide. This raises the needle by the thickness of the washer enriching the mid-range mixture just slightly. This should cure your problem.

There is one other thing that can cause this problem, a bad accellerator pump. To check this, remove the air breather cover and the air filter element so you can see into the carb. Right in front of the carb you'll see a brass nozzle standing up. With the fuel turned on and the engine "OFF", twist the throttle to the wide open postion. You should see a stream of fuel squirt into the carb. If not, you need to replace you accellerator diaphragm.

As for the connector getting hot, this is usually caused by corrosion in the connector, You need to disconnect the connector and clean up the metal contacts in both ends of this. Then, put some "bulb grease", (yeah there is such a thing used on brake light bulbs and stuff to prevent corrosion) in the connector. Silicone grease will do the same thing. If left unattended to, you're going to lose the connector.

Good Luck

Posted on Jul 29, 2010


1 Suggested Answer

  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.

Posted on Jan 02, 2017


Add Your Answer

Uploading: 0%


Complete. Click "Add" to insert your video. Add



Related Questions:

4 Answers

My alternator went out yesterday. I was told that I have a fuse and to check it first but I am unable to locate it in any of my fuse box. Does a 2005 Chevy Impala have an alternator fuse????

The red wire from starter, at the alternator, hot all the time. The orange wire at alternator, hot all the time. Use a test light on those wires, if hot, I don't think it is a fuse? Your owners manual should have the fuse layout.


Nov 01, 2015 | Cars & Trucks

1 Answer

If I pu my 2003 wide glide on battery charger and the battery is fully charged it will start as I ride and cut it off and back on a couple of times it starts to click had to push start to get home

Hi Charlie, in order to check out any main system electrical circuit, you have to start with a fully charged battery 12.5 volts or better, and be able to pass a load test if necessary.
1. Check battery terminals for damage or corrosion, check battery cables at "BOTH" ends for loose, corroded, or broken connectors, "INSIDE" and outside the cable harness, perform connector wiggle test and check cables with an ohmmeter if necessary.
2. Check the voltage drop at the battery when you hit the starter button, anything below 9 volts you might have a faulty battery.
3. Check voltage at the battery with the bike running at 3,600 RPM should be 14.3 to 14.7 volts. If you are not getting these numbers, you might have a faulty voltage regulator.
4. Make sure voltage regulator is grounded and functioning properly, watch the video below on how to test a voltage regulator.
5. Unplug the connector to the alternator and hook your multimeter leads to the alternator (pin/socket selection does not matter) set the multimeter to AC volts, at an idle the meter should read 16 to 20 volts AC. at 2,000 RPM 32 to 40 AC volts, 3,000 RPM 48 to 60 AC volts. If you are not getting these numbers, you may have a faulty rotor, follow step 6
6. Set the multimeter to OHM'S, connect one lead to the alternator (any pin/socket) and the other to a ground, the meter should read infinity. Connect both leads to the alternator meter should read 0.1 to 0.2 OHM'S. If you are not getting these numbers, you have a bad stator.
7. Check all wiring in the charging circuit for worn or chaffed spots and all wiring connectors in the circuit for corroded, broken, or loose pins/sockets, which is the # 1 offender.
For more information about your issue please visit the websites below and for specific information or questions feel free to reach me at Good luck and have a nice day.
Testing the Battery and Charging System Harley Davidson FXSTC Harley Davidson Manuals Mark Workshop
Owner Manuals Harley Davidson USA

Jul 26, 2015 | Motorcycles

1 Answer

2005 hd sportster xlc 1200 spits and sputters when taking off

Hi Roncummings1, if you have a carburator the usual suspects are:
1. Damaged or restricted fuel tank venting system (gas cap).
2. Inlet system air leak.
3. Vacuum piston malfunction.
4. Accelerator pump leaking or no output.
5. Plugged bowl vent.
6. Fuel level (float chamber) too low.
7. Restriccted fuel supply passages.
8. Plugged jets or passages.
9. Worn or damaged needle or needle jet.
10. Enrichner valve not seated or leaking.
Good luck

Jul 16, 2012 | 2005 Harley Davidson XL 1200 C Sportster...

1 Answer

Regulator/rectifier connections gets hot on 1986 goldwing 1200 sei

normal for voltage to increase with RPM, normal for voltage to decrease as battery reaches fully charged. make sure connectors are clean and tight.

Jun 30, 2012 | 1986 Honda GL 1200 Aspencade Gold Wing

1 Answer

My 09 dyna after its hot gives a real hard start battery checks out fine could the timing be off

It's very doubtful the timing could be causing this as there is nothing to move in the later model bikes. If you engine gets hard to start, it's probably your battery. Take your battery out and take it to an automotive part store and ask them to "load test" it. If it test as OK, check you charging system.

To test the charging system, first you must have a fully charged battery. You need a DVOM (digital volt ohm meter) to check the charging system. Test the entire system by connecting the red meter lead to the positive post of the battery and the black meter lead to the negative post of the battery. Put the meter's function switch in DC VOLTS, 50 VOLT range. Start the engine and bring it to a high idle. It should read 14.5-15.0 volts. If it does, your charging system is alright. If not, check the alternator.

To check the alternator, unplug the plug in the front of the engine. You can find the plug by following the two wires from the voltage regulator going down to the plug on the front of the engine. Inside the plug on the engine, you will see to metal contacts. These contacts are where you put the meter probes to test the output of the alternator. Since you'll be testing AC voltage here, it makes no differenc which meter lead goes to which connector.

Put your meter in AC VOLT, 50 VOLT RANGE. Start the engine and bring it to a high idle. Put one meter lead on each connector down in the plug. Do not allow the meter leads to touch each other or the sides of the engine case. You should read at least 30 volts AC voltage at the engine. If you do not, the stator in your bike is bad. If you do read the 30 volt minimum here but you don't have the 14.5-15.0 volts at the battery, your voltage regulator is bad.

Good Luck

Feb 27, 2011 | Harley Davidson FXDX Dyna Super Glide...

1 Answer

2001 1200 XLC lost all electrical when I hit starter. Battery connections and ground test OK. Bat reads 12.6v. Fuses in fuse box are good but there may be inline fuses or a breaker. I have an electrical...

There is a 30amp circuit breaker between the ignition switch and the starter.The charge wire from the voltage regulator goes to that same circuit breaker. There is also a 15 amp fuse in the fuse box for the ignition circuit. Double check battery cables making sure the contacts are free of corrosion. Good luck.

Oct 25, 2010 | 2000 Harley Davidson XL 1200 C Sportster...

1 Answer

If you charge the battery bike starts and runs fine.When battery gets low bike dies. Charging system not working.How do you check voltage regulator?

Unfortunately you cannot check the regulator portion of the regulator/rectifier. The common failure on these units is the stator itself, which is located in the rear of the motor and requires motor removal to replace. If you haven't done so already, check the stator connector (3 pin connector with yellow wires located near the battery). Often these leads develop resistance and get hot and melt the wires in this area. A repair kit is available from Honda with new wires and connectors. However first I would check the stator to be sure it is ok. You can check resistance between each of the yellow wires. The readings should be fairly equal and should have no continuity to ground. If you have continuity to ground, your stator is bad. You can also check AC output between yellow wires with the motor running, you should get voltage readings from about 20VAC at idle that increase to approximately 60-90VAC as the motor is revved up.
Hope this helps.

Aug 21, 2010 | 1984 Honda GL 1200 Aspencade Gold Wing

2 Answers

2003 hd ultra classic not charging,how do you test the voltage regulatorr to see if thats the problem ?

With a fully charged battery in the bike, connect a Digital Volt Ohm Meter to the battery, red lead to positive, black lead to negative. Set the meter's range to DC Volts, 20 volts or greater range. Start the bike. The meter should show a rapid build up to between 14.5 and 14.8 volts. If not, check the output of the alternator.

Look down near the oil filter and find the connector on the engine case where your voltage regulator plugs in. Unplug the connector and inspect both ends of it for broken or damaged connectors or wiring inside the plugs. Look down into the connector in the case and you should see two metal connections. This is what we're going to test next.

Put your DVOM meter into AC volts, 50 volts or better range. Make certain your meter is in AC volts as the voltage we'll be testing here is alternating current voltage. Start the bike up and bring it to a fast idle. Put one lead of the meter on each pin in the engine side connector. Since it's AC voltage, it makes no difference which lead goes to which pin. You should be reading at least 30 volts. If so, your regulator is probably bad. If not, your stator is the culprit.

Good Luck

Jul 18, 2010 | 2003 Harley Davidson FLHTCUI Electra Glide...

1 Answer

Charging problem on 2004 Harley sportster XLC

first check your battery connections and make sure they are tight and clean. Then check the voltage at the battery as well make sure it has at least 12.5 volts with the key off. Start the bike and test the voltage at the battery with the bike running, it should be around 12.8 to 13.5 VDC and if you turn the throttle up it should increase to around 14. 5 VDC anything over 15 VDC would indicate a bad voltage regulator. If you only see battery voltage, (whatever the voltage was with the key off and no more then that) I would suggest from there reading the tips and tricks I wrote on testing your charging system. Thanks for using and good luck. Let me know what you find and Ill be happy to help you further if needed. Also always check your ground connections to be sure they are tight and dry as well.

May 20, 2010 | 2004 Harley Davidson XL 1200 C Sportster...

Not finding what you are looking for?
2003 Harley Davidson XL 1200 C Sportster Custom Logo

171 people viewed this question

Ask a Question

Usually answered in minutes!

Top Harley Davidson Experts

Arnie Burke
Arnie Burke

Level 3 Expert

4521 Answers


Level 3 Expert

4339 Answers


Level 3 Expert

76070 Answers

Are you a Harley Davidson Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides