Maybe this can be made a sticky in the Evo section if a moderator deems it appropriate.

I figured we could use a thread about this since it seems like a frequently asked question. Many Evos seem to have an occasional problem known as the dreaded click. This is when you go to start the bike, but only get a "click" when you push the starter button instead of the starter engaging and turning over the engine. There are several different things that can cause the problem. Before going any farther into adding a second relay, you need to make sure that this is your problem.

Start by making sure your battery is not weak or going bad. Also make sure the contacts inside your starter solenoid are clean and not worn out. Make sure the solenoid plunger moves freely and is not stuck. Make sure all the original connections are clean and tight. Make sure your original starter relay is not going bad. If all this checks out and you still have the occasional dreaded click, read on...

From the factory, the battery current that closes the plunger on the starter solenoid has to travel through over a dozen connections and enough small gauge wire to wrap 2+ times around the bike. Every extra foot of wire and every connection in the way robs a little current from the solenoid and over time, this resistance increases from corrosion, crystallization of the wires and connections that work loose. Eventually this gets to the point that the solenoid just barely has enough current to do it's job, and it occasionally wont do it's job, hence the dreaded click.

Adding a much shorter run of larger diameter wire and a fresh relay directly from battery to solenoid allows much more current to flow to the solenoid.

The solenoid is a big relay basically. when energized, a coil of small wire creates a magnetic field that pulls the solenoid's plunger, closing the contacts inside the solenoid housing between the large-gauge wire from the battery and the starter motor itself. Over time, this coil as well as the wiring, connectors, etc has internal crystallization that builds up, reducing it's ability to flow current and increasing internal resistance. This creates heat, which compounds the problem by causing the crystallization to grow faster. If the amount of current is too low, the coil doesn't create enough of a magnetic field to pull the plunger all the way. The more current, the stronger the magnetic field, the more powerfully the plunger gets moved.

Think of it like breathing. Would you rather try to breathe through 2 feet of garden hose, or 12 feet of drinking straw? Same premise.

It might help to know there are 2 different types of automotive relays. The standard type and the switched type. The standard type is also called fog light style relays. When current flows through 85/86, it allows current to flow from 30 to BOTH 87 tabs. The switched type allows current to flow from 30 to 87a unless current flows through 85/86, then it switches the current from flowing in 30/out 87a to in 30/out 87.

Here is a list of some of the bike models and years that this should work on, although it should also work on several others as well. 86 FXRD, 86-98 FLHTC, Ultra, I, FLTC/ultra, I, 86-92 FXRT, 95 FLHT. These models use the switched type relay to kill the lights while starting, they would require the additional relay.


However on 1989-1993 FLHS, 87-94 FXLR, 86-94 FXR, 86-92 FXRS/con/sp, 95-98 FLHR, FLHR-I, 1999 FXR2 and FXR3 and older Soft Tail and WideGlide models, You could just hook up a heavier gauge, fused wire from battery positive directly to the original starter relay's "30" tab. When you connect the new wire, disconnect the original wire from the "30"tab and tape it off. You don't need to worry about the additional relay. You might also benefit from running a heavier gauge wire with fresh connectors from the original relay's "87" tab to the solenoid's input. These bikes use either a standard type of relay or if using a switched style, they just don't use the "87a" tab for anything.

Adding a second relay to the starting circuit will do two things for you: the first and most desirable benefit is feeding the solenoid the much needed current to do it's job well. The second, not-so-obvious benefit is lightening the load on the original starting circuit, making it's job easier which can help it last much longer.

Relays seem confusing, but they are actually pretty simple. Every relay I have seen has tabs marked 30, 87, 85 and 86, standard type relays usually have 2 "87" tabs while switched type relays have one "87" tab and one "87a" tab. Think of it as a remotely-controlled switch. Tabs 30 and 87 are the tabs you want to turn on/off and the other two tabs, marked 85 and 86 are the side that senses when to turn the first two tabs on or off. The middle tab is the "87a" tab on switched or another "87" tab on standard relays.

So when the relay has current going through 85 and 86, it turns "on" the current between 30 and 87. When 85 and 86 has no current through it, it will turn "off" the flow between 30 and 87. (switched relays then turn "87a" ON). Make sense?

Since we are going to be playing with the starter, make absolutely sure the bike is in neutral and disconnect the battery before starting into this!

First, you need a relay. Just about any automotive-grade relay will do, just make sure it has at least a 30amp rating. Standard Fog light relays will work just fine and are available inexpensively just about anywhere. You will also need some wire; a few feet of 14/16 gauge multi-strand automotive wire will be perfect. You can also get fancy and use a relay pigtail plug harness, or just get some flat-blade type insulated crimp-on connectors as well as a crimper/stripper tool. You will also want an in-line fuse holder, 14/16g with at least a 20amp fuse. I used 5 female flat insulated connectors, one male flat connector and 2 ring terminals.

A picture says a thousand words, so here are two of them to depict the connections you need to make:



After making all the connections, zip-tie the wires out of the way of moving or hot parts. I zip-tied the relay to the bottom of the existing starter relay under the right side cover, just under it.

Now re-connect the battery and put your bodywork back together and you're done. Now when you push the starter button, the factory circuit tells the added relay to turn on, sending more current to the solenoid than the original system was capable of. The bike starts and when you let off the button, the added relay turns off, like the factory circuit did originally.

There are other ways to do the same thing with the same results.

If you have experience with automotive wiring, relays and crimp-on connectors and would like a neater version, click HERE to jump to post 81 for a cleaner, more hidden way to do the same thing with less wire.

Here is a pic depicting another way to install a second relay, more in parallel to the original system. This way was thought up by Dr. Hess.

it works and is another way to do it.

If anyone else has any helpful advice or schematics to add, please do! Maybe we can make this the definitive dreaded click answer thread!

At the very least I hope this helps someone out there...

 

So 85 connects to the old relay and 87 connects to the green wire to the starter?

 

The wire I unplugged from the starter solenoid on my bike was a brownish-orange. That's what I connected to "85" on the new relay, then I connected "87" on the new relay to the starter solenoid where I had just unplugged the brownish-orange wire.

 

Actually now that I think about it, that would probably work as long as the "green" wire you speak of is the one that goes to the solenoid control terminal. In that case you would just pull the wire from "87" on the original relay, plug it onto "87" on the new relay, then connect a wire from the original relay's "87" terminal to the new relay's "85".

I did it the way I did to make it the easiest to remove in case that wasn't my problem. I didn't have to cut or splice any original wires. Plus I haven't looked into if the wire from the original "87" only goes to the solenoid, or if it goes somewhere else as well.

***Edit*** I just looked up the wiring for your bike, 95 FLSTC and it IS indeed a green wire, but it goes on a trip through a connector and even connects to terminal 9 on the ECM before making it to the solenoid. You're better off making the connection the way I did, at the solenoid rather than at the relay.

 

According to my wiring diagram, the factory starter relay is slightly different from a standard fog light style relay. The factory start relay connects "30" with "87a"(which is the terminal I have labelled "not used") all the time until you push the start button, then it disconnects with "87a" and connects with "87". On a standard fog light type relay, 87 and 87A both work together, not opposite.

I thought it was an orange wire, but my wiring diagram has it labelled as brown. And this brown wire connects straight from the original relay's "87" to the starter solenoid and no where else. However the wire connected to "87a" is the same color and goes to the Accessory Breaker. If you wanted to connect the new relay's "85" directly to the old relay's "87", you will have to make sure you are connecting to "87" and not "87a". The relay is labelled if you look really closely, right next to each prong.

Still sounds like the way I did it is easier, with less chance of connecting something wrong and potentially having a situation where the starter runs continuously until you press the button! LOL!

 

The start relay is usually located between the battery and the starter, right next to the main breaker. On mine it's under the right side cover.

Texashillcountry: I don't know if my wiring diagram I looked up is the exact right one for your bike, but after looking over a couple of them, I still say that connecting the relay between the solenoid and the original solenoid wire would be your best bet to avoid any other issues. Just unplug the 18g green wire from your solenoid, add enough wire to reach where ever you want to mount the new servo and connect that green wire to post "85" on the new relay. Then connect post "87" on the new relay back down to the terminal on the solenoid that you just unplugged the green wire from. Ground new relay post "86" and connect new relay post "30" through a fuse to the battery positive post or the heavy lug on the starter.

 

Yep, a very small slotted screwdriver to press the tiny tab that locks it in place.

 

A much simpler method would be to keep the existing relay, just feed it directly from the battery or the post on the starter, instead of the current setup, which gets power supplied through a zillion connectors and a mile of wiring...

 

I did some more digging and figured out: WE ARE BOTH RIGHT!

Check out this wiring diagram:


The FLSTC doesn't use tab 87a at all, so your way of wiring it up works just like you say. You actually probably didn't have to remove/tape off your connector from 30, you could have probably just added the 20amp fused wire together with the original one giving it a parallel feed. I was looking at the diagrams for the FLT, FXR, and FLH. That's where the confusion came from.

Good shortcut, Dan! It wont work on bikes that use a switched "87a" type relay, but for ones that use a standard relay or don't use the middle "87a" tab, it will work great.

 

Gotcha, makes sense now. Looking at the wiring diagrams I have here, I`m seeing early Softails get the power from the main circuit breaker (always hot) and Wide Glides look to be getting the power for 30 at the battery lead on the solenoid.

So the relay on the dressers apparently are set up to stop power to the headlights (87a) while the starter is energized. And a switched supply is the only way for that to work.

Good thread.