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...
Source: https://www.hdforums.com/forum/evo-classic-models/845084-edited-adding-a-second-relay-to-fix-the-dreaded-click.html
Posted by: collincollinfrancome0271581.blogspot.com
