Question about Harley Davidson FLSTC Heritage Classic Motorcycles

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My 1994 harley heritage developed a miss and backfiring problem.

The sparkplugs, leads, coil, ignition module, points were all repalced. the bike ran ok for a short time then the problem returned. does anyone have advice. thanks.

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  • Harley Davidson Master
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Hi John, and the usual suspects are:
1. Spark plugs in bad condition or partially fouled.
2. Spark plug cables in bad condition or leaking.
3. Spark plug gap to close or to wide.
4. Faulty ignition coil, module and or sensor.
5. Battery nearly discharged.
6. Damaged wire or loose connections at battery terminals especially the negative cable at "BOTH" ends, ignition coil, or plug between ignition sensor and module.
7. Intermittent short circuit due to damaged wire insulation.
8. Water or dirt in fuel system, carburetor or filter.
9. Fuel tank vent system plugged or carburetor vent line closed off.
10. Carburetor controls misadjusted.
11. Damaged carburetor or intake seals.
12. Loose or dirty ignition module connector at crankcase.
13. Faulty MAP, CKP, and or CMP sensors.
14. Incorrect valve timing.
15. Weak or broken valve springs.
16. Damage intake or exhaust valve.
For a prime suspect please visit website below.
Good luck and have nice day.
Harley Davidson Wiring Diagrams and Schematics

Posted on Jun 23, 2015

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SOURCE: Rear cylinder not firing

95 Evo, new plugs, new wires, started backfireing like a machine gun, front cyl. no spark at plug sometimes - would this be the coil, have not ohmed the coil yet . Thanks

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SOURCE: how to shut off alarm on a 2002 harley davidson heritage soft tai

I long push on the remote turns it on, 2 quick clicks turn it off.

Posted on Jun 26, 2009

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SOURCE: what makes my bike backfire, I put new sparkplugs

sometimes you might need to put a better grade of gas in

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SOURCE: 19-95 KLF300 ATV Kawasaki 4x4 no spark put new ignitor unit on.

i ******* hate my kawasaki kdx 125 1992 there is no spark and i dont no wot it needs ive bought a cdi for it an it wernt that and i bought a new coil and it wernt that either could anyone help me please

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SOURCE: harley davidson flstc heritage softail 1997

The fork oil is a very specific job needing a manual and a special tool, I don't want to insult anyones mechanical knowledge but if you have never done it before, best to take somewhere else. Engine oil on the other hand is easy, the drain tube to any softail is on the right side by where the frame meets the swing arm, has somekind of plug in it. Start and run bike for a little while, long enough to get it warm but not hot. Remove fill plug and then remove plug in drain line. Using a peice of cardboard or something put in between filter and frame , directing the oil to your drain pan instead of where ever it goes. Put 1 qt oil back in (after everything is reinstalled) start the bike and make sure the oil light goes out, when it does shut bike off and fill to the point that when it is standing upright you get a little oil on the tip of your finger, over filling may result in loss of oil cap from pressure (been there)

Posted on Feb 16, 2010

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