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1984 FXRSDG shuts down


I would check the ignition trigger in the cone first, that is where H D had most of its problems JMO
 
The uploaded sheets don't state what type of trigger it is. I was just trying to get a few questions in the back of my mind answered. If the sensor plate was photocell you would not need oil droplets to be leaking past the seal in order for it to be a problem. Crankcase vapors would be enough to cause photocell miss-fire issues. The sensor plate is probably reluctance. Almost all photocell setups that I have seen were aftermarket products. It is just a unanswered question in my mind.

Reluctance pickups do fail just like crank triggers do. They have permanent magnets that get weak with time. Heat makes components drift slightly in value. The combination of both will shift your threshold trigger point over to the failure side. I feel your down to 1 of 3 components. It should not be too too hard to find but it takes some troubleshooting. If the bad parts just jumped out and said Hi, anyone with no experience or circuit understanding could do it. Your doing Great so far. Even if you draw dead,, you are gaining knowledge that will make you even better for the next time.

Test the Module & coil and see what happens. Just wish they gave us more in depth info as to what type of trigger it was. All they show is a "cable" and not individual wires on the trigger unit. I guess they don't trust us knowing too much. :p
 
The uploaded sheets don't state what type of trigger it is. I was just trying to get a few questions in the back of my mind answered. If the sensor plate was photocell you would not need oil droplets to be leaking past the seal in order for it to be a problem. Crankcase vapors would be enough to cause photocell miss-fire issues. The sensor plate is probably reluctance. Almost all photocell setups that I have seen were aftermarket products. It is just a unanswered question in my mind.

Reluctance pickups do fail just like crank triggers do. They have permanent magnets that get weak with time. Heat makes components drift slightly in value. The combination of both will shift your threshold trigger point over to the failure side. I feel your down to 1 of 3 components. It should not be too too hard to find but it takes some troubleshooting. If the bad parts just jumped out and said Hi, anyone with no experience or circuit understanding could do it. Your doing Great so far. Even if you draw dead,, you are gaining knowledge that will make you even better for the next time.

Test the Module & coil and see what happens. Just wish they gave us more in depth info as to what type of trigger it was. All they show is a "cable" and not individual wires on the trigger unit. I guess they don't trust us knowing too much. :p
Hoop, The MOCO had lots of problems with V fire 1 2 and 3 maybe thats why we cant get the info we need, my experiences always went to the pick up assembly been bad , it lives in a hostile environment even for cutting edge electronics of the day JMO
 
So just a quick recap. If it has anything to do with the cone, that ties into the ignition mod so all I need, is to replace that?

If it's the coil, replace that?

I can get both used on Ebay for 150 bucks. They charged me 161 just to fix that stupid fuel leak.
 
So just a quick recap. If it has anything to do with the cone, that ties into the ignition mod so all I need, is to replace that?

If it's the coil, replace that?

I can get both used on Ebay for 150 bucks. They charged me 161 just to fix that stupid fuel leak.

If the trigger in the cone is bad you have solved all your problems with less money spent. Check it out first, throwing parts at it may get you going but how many and then you may never know what part it was that failed, always try to eliminate the obvious, and develop good trouble shooting kills, JMO:s
 
Hoop, The MOCO had lots of problems with V fire 1 2 and 3 maybe thats why we cant get the info we need, my experiences always went to the pick up assembly been bad , it lives in a hostile environment even for cutting edge electronics of the day JMO

That early "shutter" design looks like optical sensing which was "KNOWN" to be unreliable...think LED and PhotoSensitive Cell living in the harsh nose cone environ. (both deteriorate with heat). It was technology of the day that lasted only a couple years in the industry and was GONE...the magnetic tooth / reluctor system lasted much longer and proved more "heat resistant"....maybe 7 years by various manufacturers...Chrysler being the most prevalent...but Hall effect type (moving metal in proximity of an electromagnetic field) is what everyone uses nowadays.:s

Because of the difficulty troubleshooting the nose cone assembly, I would opt with the ignition coil only because access is easier without "invasive surgery" JMO (though from Jack's experience, the nose cone electronics is more likely suspect).
 
So just a quick recap. If it has anything to do with the cone, that ties into the ignition mod so all I need, is to replace that?

If it's the coil, replace that?

I can get both used on Ebay for 150 bucks.

Paul, from what your writing it sounds to me like your really not clear on the steps your taking and the reason why your taking them. I may be wrong, but it does not sound like you have a good grasp on what is going on. If something needs more detail, just let me know.

The nose trigger electronics gets the ball rolling by determining the PRECISE time the spark should be fired. The ignition module throws or switches the heavy current needed to drive the coil. It may also include electronics to limit the rpm of the engine. It may also include electronics to adjust the spark advance curve. The coil is a simple 100:1 ratio transformer that takes the 250 volt primary voltage and multiplies it by 100 to obtain the 25KV needed to jump the spark plug gap.


If it really is a Photo-cell shutter trigger pickup, I can tell you that even just crankcase vapors getting past that seal will create a problem. I just can not determine what was used on that shutter system (photo or reluctance/hall effect). There is a very good chance that photo was used because of the slow RPM that is encountered for the shutter wheel (1/2 crank RPM).

Buying used parts like these on e-bay can be very risky. Especially if they are as old as your parts.
 
Paul, from what your writing it sounds to me like your really not clear on the steps your taking and the reason why your taking them. I may be wrong, but it does not sound like you have a good grasp on what is going on. If something needs more detail, just let me know.

The nose trigger electronics gets the ball rolling by determining the PRECISE time the spark should be fired. The ignition module throws or switches the heavy current needed to drive the coil. It may also include electronics to limit the rpm of the engine. It may also include electronics to adjust the spark advance curve. The coil is a simple 100:1 ratio transformer that takes the 250 volt primary voltage and multiplies it by 100 to obtain the 25KV needed to jump the spark plug gap.


If it really is a Photo-cell shutter trigger pickup, I can tell you that even just crankcase vapors getting past that seal will create a problem. I just can not determine what was used on that shutter system (photo or reluctance/hall effect. There is a very good chance that photo was used because of the slow RPM that is encountered for the shutter wheel (1/2 crank RPM).

Buying used parts like these on e-bay can be very risky. Especially if they are as old as your parts.

20.00 to win on the pick up assembly bad, I have seen alot of them fail, once saw a new Superglide not even make it out of the parking lot with this problem, back in the day poor at best, my 80 FLH did it too now that I think about it but I didnt keep it long LOL
 
I have seen alot of them fail, once saw a new Superglide not even make it out of the parking lot with this problem,

Jack, no kidding,, that bad. Heck, I am chicken. I will put $20 to PLACE, and another $20 to SHOW.

We do know it's not the supply voltage, and it's probably not a fuel issue (?)... We are either going to "Clean House" or go broke on this one!..:p

Oh man, I could sure use the dough!!
 
Jack, no kidding,, that bad. Heck, I am chicken. I will put $20 to PLACE, and another $20 to SHOW.

We do know it's not the supply voltage, and it's probably not a fuel issue (?)... We are either going to "Clean House" or go broke on this one!..:p

Oh man, I could sure use the dough!!

We win, so does the OP:s I would change it to after market and be done with it after finding out this is the problem JMO
 
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