I've been troubleshooting this problem for a long time and I'm about to give up and turn it over to a shop. But I thought I would try and post here and see if I get any new ideas.
Everytime I try to start it the engine stalls on the compression stroke and the battery voltage drops to 5v.
I changed a bunch of parts. Starter, battery and cables, main wiring harness, ignition system and ignition switch, new handle bar switches. I'm thinking it's voltage leaking to ground but I can't find it.
I made a video and posted to YouTube demonstrating the problem.
Here's the link : https://youtu.be/Esa8oUDEehI
Any thoughts will be greatly appreciated.

 

Not being a smart axx, but just how are you determining this engine quits on compression stroke? Just curious... That said, you probably should consider taking it to a shop.

Your probably going to hear some new member protocol tips soon.

Welcome to the HD forums.

 

I am curious too how he knows it stalls on the compression stroke. Is it firing? Do you have spark?

Did you change the handle bars before or after it started having issues? You wouldn't believe the ****ed up handlebar installs. Guys swearing they wired it right, but now it won't run.

 

It is easy to tell when a starter stalls on the compression stroke, the starter slows down big time and barely turns, but as the piston passes through TDC, the starter picks up speed again.

My `89 Softail still has the original starter, and does this all the time, the `89 model year was the first of the modern starter configuration, but the starter motor did not have a lot of power.

Kruzer88:

Don`t get all bent out of shape, but I`m guessing that you don`t have a lot of experience or understanding with electrical troubleshooting, judging by the amount of parts you have replaced.

Voltage doesn`t leak to ground, it shorts to ground, and a short is easy to find.

Your issue is not being caused by a short.

If you are reading voltage at the battery posts, with a voltmeter (not using the meter in the dash), and the voltage drops to 5V when the starter is cranking, the battery is junk, or it is not fully charged.

 

Have you done any work in the cam chest since last starting the bike? This engine doesn't even get through on revolution, have you had the rockets off or pushrod out? This could be a mechanical issue.

 

[QUOTE=Dan89FLSTC;19107879]It is easy to tell when a starter stalls on the compression stroke, the starter slows down big time and barely turns, but as the piston passes through TDC, the starter picks up speed again.

My `89 Softail still has the original starter, and does this all the time, the `89 model year was the first of the modern starter configuration, but the starter motor did not have a lot of power.

For many of us that’s a good call. Just from the OP description and attempts is cause for question determining that imo.

like I said it might be best to seek help from a shop at this point.

 

[QUOTE=Taggs;19108470]There is nothing magical or mysterious about the starter circuits on a Evo Softail, it is about as basic as it gets.

The OP has already replaced a starter, so I will give him credit for being able to work on the bike himself (you would know what I mean if you had ever replaced a starter on an Evo Softail).

I think the OP can find the issue with our help, if he is willing...

 

[QUOTE=Dan89FLSTC;19108511]Right on.😬

 

My apology to the OP if my posts were taken in a unfavorable way. This should be a place to find answers not criticism.

After reading your opening post again it would seem you’ve eliminated some potential issues. Going a step further I would make sure the basics are in working order. Simply put, getting fuel and fire to the plugs. With that check complete and same results, I’d be looking at timing. First place would be pull the points cover to check if possibly the points plate is secure or may appear tight but moved out of position. Your service manual should provide the best description for timing the engine. Even without any special tools you can get it set close enough where the bike should run. That engine should take off!

Good luck!

Let us know what you find.

 

[QUOTE=Taggs;19108470][QUOTE=Dan89FLSTC;19108511][QUOTE=Taggs;19109523]Sorry for the late reply guys. Thanks a lot for the questions and suggestions.
Here's a little more detail on my problem.
When trying to start, the motor stalls and the battery voltage drops to 5v. I have pulled the plugs out to see if it stalls on the start. Result: It will turn over a few times(with plugs out) until the battery drains to 5v. This happens with a new battery rated at 310 CCA.
The bike was running until I decided replace the oil seals for the oil return hole in the heads because they were leaking pretty bad. BTW I have a Sputhe 95 inch motor with Branch heads.
After getting the motor put back together that's when the starter problem began and have been working on it for 3 years off and on. I would get frustrated and leave it alone for a month before I would try working on it again. Plus I don't have a garage, just a carport, and it gets a little too hot in the summer or too cold in the winter to work on it here in Oklahoma.
I am an industrial technician so I have training and trouble shooting skills in electrical and mechanical.
I know the electrical system on the 91 softail is as basic as it gets but I guess that I have gotten so frustrated with it that I have just can't figure it out. That's why I resorted to replacing parts even it the part seemed good. I do have the service manual with schematics.
I had taken my bike to a local dealer but since they won't work anything older than 2000 (WTF?) they sent it to a custom bike builder/mechanic last year and he had it for 6 months and couldn't get it working either. He replace the handle bar switches when he found that they were corroded but that didn't help the starter stalling problem.

Parts replaced:
Handle bar switches
Ignition key switch
Ignition switch harness, the short side from key switch to main harness.
Main harness that covers the ignition system but not the other 2 bundles from the lighting and handle bar. I wanted to replace the harness when I found 3 wires were corroded at the pin connectors.
Starter
Ignition system- Dyna 2000i
Battery and battery cables
After all that there is still a problem. I even tried putting the ground battery cable directly connected to the starter body, thinking I had a bad ground to the frame, but that made no difference.
So my thinking is that it has to be a wiring problem so maybe I need to replace the other 2 wiring harness connectors even though Ii can't see how that could be the problem.
Also I can't tell if I'm getting a spark or not since the motor won't turn over. And when I pull the plugs to see if a spark is there when cranking it, the voltage drops too fast to make a spark.
Only things I haven't changed are the coil (plug wires are new), stator and regulator. Is it possible one of those things is the reason I'm dropping voltage when the starter stalls?

Thanks for taking time to read this.