Hi,
I've run across an issue with starting on my 1985 FXRS SP (yes it is an SP [EG] even though officially the SP did not come out until 1986) that does not make sense to me. I bought the bike brand new. It is bone stock. It did sit for a while (other bikes took precedence). What led up to this was rebuilding the Keihin butterfly carb along with replacing the fuel inlet. Replacing the fuel inlet was a challenge, none fit properly without a lot of effort. It was so bad that one was completely destroyed when trying to press it in. I also replaced the fuel inlet line and checked flow from the gas tank. Anyways, all that has been resolved. Now on to the starting problem.

I have a situation where there is plenty of cranking power but the plugs do not fire. Since I had a brand new coil I just replaced it with no success. I used the Harley Service Manual to troubleshoot the problem. Below is what I did and the results.

1. Checked power to the coil - good.
2. Removed the blue trigger wire, turned on ignition, checked power to both terminals - good.
3. Replaced the blue trigger wire, saw spark at terminal.
4. Engine started but stalled.
5. Noted that the battery needed to be tightened down - completed.
6. Tightened the battery posts - completed.
7. Bike did not start.
8. Repeated steps 2 & 3 (multiple times), bike finally started and kept running, let it get to normal operating temperature.
9. Shutdown engine
10. Removed air cleaner and backing plate, started engine normally.
11. Adjusted high speed idle for 1500 rpm at first choke detent.
12. Adjusted low speed idle for 1000 rpm at full open choke.
13. Shutdown engine.
14. Put backing plate and air cleaner back on.
15. Started engine normally.
16. Rode around the neighborhood at 30 mph in 3rd gear - no issues.
17. Upon return noted idle at 1200 rpm.
18. Reduced idle to 1000 rpm.
19. Shutdown engine put bike away.
20. Following morning - bike would not start. I did not take blue trigger wire off coil since I really did not want to remove the coil again at this time.

Anyone have ANY ideas on what could be the problem? I checked all ground connections. I can't see anything in the schematic that might be an issue.

HELP!!

LDR

 

All well and good... does it Crank??? then not start?
If no fire to Plugs... start with the Pick-up...and if that don't cure it... Control module.....since you already replaced coil...

 

How long was it sitting?

-Pull plugs to see if plugs fire when cranking engine
-How old is the gas? Last adjustments was with carb, so that's something to look at if it's clogged with debris

 

I would test the coil with a multimeter still (I have gotten bum plugs before im sure its possible with a coil too), i have the Harley factory manual if you dont, and can give you all the specs, (I have a 85 FXRT I know pretty well) I just forget everything,

 

Do you have spark when you crank it? Stick a screwdriver in the end of the plug wire, hold close to ground, crank. If you have spark, you have a fuel problem.

 

Check your cam sensor.

 

Agreed with THC check your cam position sensor, as well check your breakers.

 

He dinks with the carb and has starting problems. A carb that is >30 years old and was a total POS when brand new. First check and see if you really have a no-spark condition.

 

I disagree that the original Ka-sneeze is a POS... if it is Not worn at the throttle shafts [like any old Carb] it is as good as any...especially for a stock 80 incher..
if half of the time. print, forum etc effort was spent on the Ka-sneeze, as is spent/expended on tuning say an S&S [google S&S tuning and get an idea!!]
more knowledgeable folks would be running the old Butterfly Keihin...and/or the Bendix for that matter...
now... we still don't know if we have Spark....so here we sit at the side of the road wishing we had a Shiny new Twinky....

 

My 82 FXR had starting issues till I changed out the battery cables and did a wire wheel buff on all the grounding points not just tightening down. Popped, cleaned and lubed all the snap connectors to. More common an issue on these older bikes than you might think. All it takes in one intermittent contact that shows continuity when checking but breaks down under load to make you pull your hair out.