coil relay mod? gs 450

[mrameswmartin]

i attempted to put a relay mod in last night but didnt quite understand the process . i used the pdf from basscliffs site but wires and harnesses didnt seem to match up on my 81 450. has anyone done this on a 450? or maybe has a "how to" for the electrically ignorant such as myself?

[pete]

I haven't looked at it myself as I was able to clean up my harness enough to get rid of most of the voltage drop, but on my '82 450E, both coils are fed from an orange/white wire and are grounded by the ignitor.

The orange white wire comes from the kill switch and start button, and connects to both coils and the ignitor.

I imagine you could splice into this one anwhere that seems appropriate and use it to turn a relay on instead.

It seems the equivalent wire on yours should be orange/white if it's a L or T, otherwise a yellow/white. That's what the Clymer tells me anyways...

[mrameswmartin]

so the ignitor only grounds the coils? i thought it was like a capacitor..how exactly does it work?

[Steve]

so the ignitor only grounds the coils? i thought it was like a capacitor..how exactly does it work?

If you understand the concept of how the coils produce the sparks when points open, stopping the flow of current through the coils, it is very easy to just tell you that the ignitor is "electronic points". There is nothing really magical in there, it's just a set of heavy-duty transistors (and the bits and pieces that make them work) that switch the current coming from the coils.

The "coil relay mod" assures full voltage and current to the coils, but is really only useful if your are getting considerably less to the coils right now. To see if you actually need the mod, measure the voltage at the orange/white wire at the coil, compare that with battery voltage. If there is more than a volt or so difference, you might benefit from the mod. You would actually be better off cleaning the connections in the harness between the battery and the coils. The mod only bypasses all those "bad" connections.

.

[Tenrilid]

Question on the coil relay mod. I attempted to do this yesterday as I was only getting 3-4v on each coil but once I installed everything how the directions say to do except for 1 thing, the grounding. I need to know if I must connect the ground wire for the relay to the main ground wire in the harness or if it can be connected to any ground.

[mike_of_bbg]

Question on the coil relay mod. I attempted to do this yesterday as I was only getting 3-4v on each coil but once I installed everything how the directions say to do except for 1 thing, the grounding. I need to know if I must connect the ground wire for the relay to the main ground wire in the harness or if it can be connected to any ground.

Any ground should do. The ground is only for the relay to operate.

You were only getting 3-4V at the coils? Or are you talking a 3-4V drop from bike voltage? I can't imagine a bike possible starting with only 4V at the coils! Is your battery health OK? Sounds like you need to do some thorough wiring cleaning. I'm not sure 3-4V could operate a relay!

[Tenrilid]

well, the bike still wont start and I was only getting 3-4v at the coils. the battery showed a strong 12v so I know it's not the battery. I have the feeling I may have been doing the coil reading wrong though.

[mike_of_bbg]

Are you sure you're not talking 3-4 OHMS at the coil? That would be normal. For the voltage, set your DMM to DC 20V range (probably) and use the probe to pierce the two wires at the coils while it's connected, bike on, ignition on, and get the reading between them.

3-4V is way low. WAY low. The igniter usually runs off of the same switched B+ that the coils do, not sure 3-4V could get any love from that even if you fixed up the coils using the relay. Could be a big drain or more likely some really bad connections.

[Tenrilid]

I do mean volts so it seems like I will need to check the readings at the ignitor. the ignitor should be good as I got it from ebay and the auction stated the bike was running prior to removal.

Let me also check, the positive line going to the coils should show a reading w/out having to crank the engine right? Just as long as the ignition is on?

[mike_of_bbg]

Yes, the coils always get B+ with the ignition on, no need to crank or have it running. The GROUND is what the igniter pulls to create the spark. Don't leave the coils energized without the motor running any longer than you need to.

[Tenrilid]

ok, this may make me sound like a tard but what's B+? I'm assuming Battery Positive power but want to clarify.

[mike_of_bbg]

Confirmed...

ok, this may make me sound like a tard but what's B+? I'm assuming Battery Positive power but want to clarify.

[Tenrilid]

Just thought of something. I picked up a 30a inline fuse for my coil relay mod, is that too large of a fuse to use?

[mike_of_bbg]

That probably is too large for the wire you're using - 10A should be fine (it was stock). However, that's not going to cause your bike to not run. Do you know what's going on? Is your relay clicking when you turn on the ignition?

[Tenrilid]

Well, I hadn't noticed if it clicked when I turned on the ignition but I did noticed it clicked when I was disconnecting/reconnecting the battery.

At first I thought it was something arcing from a bad connection so it freaked me out at first.