I have on and off problems with my 1991 FLT getting enough power from relay to starter solenoid to engage the solenoid. I already have a mechnical button on my solenoid and I understand the reasons for the problem, I just won't to fix it for good. I have read posts about adding a 2nd stater relay under seat to furnish positive wire directly from battery to starter. Question is; rather than a 2nd relay, why can I not just run a positive wire from battery starter lug and pigtail (I believe that is correct term) it to the existing positive wire coming into the starter relay? The original relay would still control power to the solenoid, however there would now be an added direct line from the battery. There must be a reason this is not done and the 2nd relay is used. I have looked all over the site for a wiring diagram with the 2nd relay (I believe by "Dr Hess"). Does anyone know were this diagram is located. Thanks!!

 

An idle starter solenoid can receive a large electric current from the car battery and a small electric current from the ignition switch. When the ignition switch is turned on, a small electric current is sent through the starter solenoid. This causes the starter solenoid to close a pair of heavy contacts, thus relaying a large electric current through the starter motor, which in turn sets the engine in motion.

If a starter solenoid receives insufficient power from the battery, it will fail to start the motor, and may produce a rapid clicking sound. The lack of power can be caused by a low battery, by corroded or loose connections in the battery cable, or by a damaged positive (red) cable from the battery. Any of these problems will result in some, but not enough, power being sent to the solenoid, which means that the solenoid will only begin to push the engagement gear, making the metallic click sound. Starter solenoid problems are best diagnosed by an experienced auto-electrician.

From the sound of your post, and I am reading between the line. Your problem may be that the selinoid is not getting sufficient power. Have you looked at replacing the selinoid contacts inside the selinoid. They are cheap and are the reason most starters give trouble. Hard starting and low batteries will wear out the contacts very fast.

 

Busterman, if you do it that way, then your bike will be powered all the time, regardless of the position of your ignition switch. There's a thorough writeup here somewhere. Here's a copy of it:

https://www.hdforums.com/forum/evo-c...uestion-2.html

 

Thanks Dr Hess! I had not throught of power on all the time. I will work on installing the 2nd solenoid.

 

Huh, second selinoid! Why didn't I think of that?

 

Second relay, really. Although technically "relay" and "solenoid" are the same thing, in common usage, "solenoid" is the BIG relay that switches the main line from the battery to the starter and "relay" is the little relay that activates the "solenoid."

 

I recently added a second relay to mine and haven't had a click since! I did it a little simpler than Dr. Hess, though.

Step 1: 14/16g wire from battery positive to the one terminal on the new relay oriented 90 degrees to the rest.

Step 2: Another 14/16g wire from the terminal of the new relay directly across from the one you just used in the last step to the solenoid terminal that has a 18g wire connected to it. Unplug this wire when you plug in the new wire.

Step 3: Take the 18g wire you just unplugged and connect it to one of the side terminals on the relay.

Step 4: Connect the other side terminal of the new relay to a good ground.

Step 5: Tuck everything out of the way and you're done.

It really is that simple.

 

Just to clarify a couple things:

Step 1: 14/16g wire from battery positive to the one terminal on the new relay oriented 90 degrees to the rest. You should probably add a fuse of say 20amps or so within 6" or so of your Battery positive connection. You can make the connection at either the positive post of your battery or the heavy lug on the starter(which is actually the other end of the battery positive cable).

Step 2: Another 14/16g wire from the terminal of the new relay directly across from the one you just used in the last step to the solenoid terminal that has a 18g wire connected to it. Unplug this wire when you plug in the new wire.

Step 3: Take the 18g wire you just unplugged and connect it to one of the side terminals on the new relay.

Step 4: Connect the other side terminal of the new relay to a good ground.

Step 5: Tuck everything out of the way and you're done.


This setup is totally removable and does not require any cutting into or splicing into the original wiring. The new relay now feeds stronger battery current through much fewer connectors and shorter wire run directly to the starter solenoid, giving it the current needed to pull the solenoid plunger better than it could before. The original relay now controls the added new relay rather than feeding the solenoid like it used to.

This setup is simpler, easier to accomplish and is less invasive to the original factory wiring than the piggy-backed relay setup, yet provides the same end result. Like it has been said before though, this wont cure your problem if your solenoid contacts are worn out, dirty or carbon-ed up beyond making a good connection.

In my case, the inside of the solenoid housing was very shiny-golden and looked perfect. The solenoid was just not getting enough current to overcome the resistance of over a dozen connections and enough wire to wrap 2+ times around the bike to have enough left over to pull the plunger strongly enough.

Make sense? If anyone has any questions, let me know.

 

I am going to try and sketch this out, I have trouble following the written descriptions. Does anyone have a sketch of the wiring on this? Thanks!!

 

Give me a little bit and I will go take a pic of a relay, label it up in paint and post it up for you.