Coil relay mod on a GS750E

I disagree about not grounding the motor to the battery negative. That is your starter motor negative. The single point ground doesn't mean that you can't run from battery negative to the motor and the single point ground at the same time. Eliminating the frame and bolted together components as the main ground (or improving it) is the point of providing as close to battery negative as you can get for the entire bike by using a single point ground near the R/R and spidering out to other grounding points from there with appropriate size wire to compensate for distance. You can't eliminate the frame ground by design, but you can eliminate almost all it's inherent faults.

Find posplayr's thread on grounding to a single point. Follow his directions.

The engine should not be grounded directly to the negative terminal of the battery.

Hmmmm. The negative battery cable runs from the battery to the engine (well, really to one of the bolts on top of the transmission case). Maybe this bike was assembled wrong at the factory, or maybe the dealer goofed it up when it was under warranty. Where is the threaded bolt hole on the frame for the negative battery cable to be attached to?

The engine should be grounded to the frame at the same place everything else is grounded, then that bolt should be grounded to the negative terminal of the battery.

So is there supposed to be a ground strap between the engine and the frame? Any idea where that ground strap is attached to the engine and where it is attached to the frame. How long a ground strap will I have to get? (Sounds like I'll have to make a trip to the city next week to see if that ground strap is available from the Suzuki dealer.) Is it one of those woven straps?

The engine should be grounded to the frame at the same place everything else is grounded,

Looks to me like the black/white strip wire is grounded in multiplt places based on the wiring diagram: the rear turn signals are grounded back near the rear turn signals, the front turn signals are grounded up near the front turn signals, the starter relay is grounded to the mounting plate, the mounting plate is grounded through the black/white strip wire, the black/white strip wire is also attached to the battery box, as is the ignitior. Are you saying that we need to run grounds from the engine to each of these places?

The engine should not be grounded directly to the negative terminal of the battery. The engine should be grounded to the frame at the same place everything else is grounded, then that bolt should be grounded to the negative terminal of the battery.

Okay. I hope to go to town tonight and see if I can find some heat shrink that will fit over the ring lugs.

Meanwhile, I struggled for nearly an hour to remove the bolt that holds the negative battery cable to the transmission only to find out that after I loosened it, there is not enough room to extract that long bolt while the airbox is in there, and I'm NOT removing the airbox again. (Before reinstalling the carbs we removed the bolt and cleaned up its ring and where it contacts the transmission, so I know that end is good.) So I decided to clean up the battery end of the negative battery cable while it is dangleing along side the bike.

Here is what I found :



It is hard to see what with my photograpy skills, but I slit open the heat shrink and it is also loaded with greenery. I think it must have something to do with the fumes from the battery as only the battery ends of the battery cables had this "stuff" (trademark).

So I gave it the baking soda, navel jelly, vinegar, detoxit wash, compressed air treatment, and............



Then I abused it with my soldering iron..........



It doesn't look as bad as it looks in that picture. (Don't let it hurt your eyes.) But with my DMM on the battery end of the negative battery cable (as seen in the above pic) I get 0.0 ohms to anyplace on the engine.

BUT HERE IS WHAT I DON'T UNDERSTAND. From this ring lug to any point on the frame I read between 0.2 and 0.3 ohms. Same thing from any point on the engine to the frame, same reading.

Trying to follow the wiring harness on the bike and my 1980 GS750E wiring diagram, it appears to me that all the asundry loads (except the starter) are grounded to the FRAME. How is the frame grounded to the engine (since the engine is grounded to the negative battery post via this negative battery cable)? Is the engine mounted in rubber? Or do I need to remove all the engine to frame bolts and shine them up? Or should there be a frame to engine ground strap that maybe I haven't found yet?

Thanks for sticking with me this far...............

[posplayr]

So, I'm back

Pulled that positive baterry cable and it didn't appear to be too bad.


Until I took a closer look at where the lug emerges from the shrink wrap.


Looks like greeny has been living under the shrink wrap. So I cut the shrink wrap off and lookie what I found:



That crimp-on is just PACKED with green growth! So I soaked it in baking soda, soaked it with navel jelly, then soaked it with vinegar, flushed it off with water and dried it with compressed air. See the results below.


Stay tuned....................

I knew there had to be something to account for that 0.17V

I bet you are well under 0.1V on the positive side now.

If you have looked at the SSPB you will probably understand why I have the R/R(+) and the Battery(+) directly connected together on entry to the SSBP so that chasing down this nonsense is eliminated.

You still need the Single point ground but most people get that pretty much first time when they know what to do. Actually I have simplified that as well, but that is also something that anyone could do as well.

http://www.thegsresources.com/_forum/showthread.php?t=210261

Just went out and looked at it more closely. It has a very nice 'red' shrink wrap covering the connection of the brass ring lug. But I think I can see a little green showing at the very edge of the shrink wrap. When I get back (heading out of town for a week) I'll pull that battery cable out of their and cut the shrink wrap off and give it a chemical cleaning and inspection. If its solid I'll then solder it! Thanks for the suggestion.

So, I'm back

Pulled that positive baterry cable and it didn't appear to be too bad.




Until I took a closer look at where the lug emerges from the shrink wrap.




Looks like greeny has been living under the shrink wrap. So I cut the shrink wrap off and lookie what I found:



That crimp-on is just PACKED with green growth! So I soaked it in baking soda, soaked it with navel jelly, then soaked it with vinegar, flushed it off with water and dried it with compressed air. See the results below.



Then I tried my hand with the soldering iron:



Sorry for my poor photography

Anywho, can't wrap (no pun intended) this up yet as I now need to find some shrink wrap that will fit over the ring lug and I'll be ready to run my final numbers.
Stay tuned....................

[posplayr]

No coil relay mod. All through the standard (cleaned up) wiring. Thanks to YOU!



No. Never thought to look that closely at it. It seemed to be pretty solid connection, well covered with shrink wrap and a rubber boot..
Just went out and looked at it more closely. It has a very nice 'red' shrink wrap covering the connection of the brass ring lug. But I think I can see a little green showing at the very edge of the shrink wrap. When I get back (heading out of town for a week) I'll pull that battery cable out of their and cut the shrink wrap off and give it a chemical cleaning and inspection. If its solid I'll then solder it! Thanks for the suggestion.


Even though I have purchased the connectors, I see they take up a lot of real estate. I saw where someone ( maybe it was you) just slide female spades into the SH775 R/R + RTV to save space. I also want to look at the length of my wires running to the ignitior. Someone suggested that it may be possible to mount the R/R where the ignitior lives (GS750E) and move the ignitor to the stock R/R location.


I'll put my coil relay parts in storage just it case it comes to that.

Good work, I'm surprised you got the voltage drops through the ignition switch and fuse box so low ; doesn't sound like you need the relay mod.

That is very good. So did you do a coil relay mod or is all that voltage through the standard paths?

No coil relay mod. All through the standard (cleaned up) wiring. Thanks to YOU!

The 0.17V is under the 0.25V and is probably not something to worry about but there is obviously some more corrosion some where. Did you solder the Battery(+) ring lug?

No. Never thought to look that closely at it. It seemed to be pretty solid connection, well covered with shrink wrap and a rubber boot..
Just went out and looked at it more closely. It has a very nice 'red' shrink wrap covering the connection of the brass ring lug. But I think I can see a little green showing at the very edge of the shrink wrap. When I get back (heading out of town for a week) I'll pull that battery cable out of their and cut the shrink wrap off and give it a chemical cleaning and inspection. If its solid I'll then solder it! Thanks for the suggestion.

In order to avoid using that large OEM connector on the SH-775 you can also use individual spade connectors and RTV to fill the entire connector cavity. This saves quite a bit of space.

Even though I have purchased the connectors, I see they take up a lot of real estate. I saw where someone ( maybe it was you) just slide female spades into the SH775 R/R + RTV to save space. I also want to look at the length of my wires running to the ignitior. Someone suggested that it may be possible to mount the R/R where the ignitior lives (GS750E) and move the ignitor to the stock R/R location.

I have mentioned this before that wench I did my GS1100ED, I bought all new harness with new left and right hand controls and a new ignition switch and after about 2 years the thing was becoming hard to start so much I had to resort to starter fluid. After doing a coil relay mod, it starts instantly.

I'll put my coil relay parts in storage just it case it comes to that.

[posplayr]

I didn't want to solder them on until I get my next project underway (which will prolly be in a month or so). I got me a SH775 and need to figure out where there is room for it.

Well, here's my final numbers after cleaning and soldering the "T" connection deep inside the wiring harness:

Voltage @ Battery....R/R + lead drop.....R/R - lead drop.....Volts @ Coil.
1100rpm = 14.3 volts____0.17 volts_______0.00 volts______13.2 volts
2500rpm = 14.4 volts____0.16 volts_______0.00 volts______13.4 volts
5000rpm = 14.4 volts____0.17 volts_______0.00 volts______13.7 volts.

What an amazing difference! I don't even have the carbs sync'd or adjusted yet - when I press the starter button it starts so quick you can't even hear the starter engage!

That is very good. So did you do a coil relay mod or is all that voltage through the standard paths?

The 0.17V is under the 0.25V and is probably not something to worry about but there is obviously some more corrosion some where. Did you solder the Battery(+) ring lug?

In order to avoid using that large OEM connector on the SH-775 you can also use individual spade connectors and RTV to fill the entire connector cavity. This saves quite a bit of space. On my original MOSFET R/R (that burned up my Electrosport stator), I even avoided the spades by soldering directly to the male spades. I pushed them over and drilled small holes to push the wire through before soldering.

I have mentioned this before that wench I did my GS1100ED, I bought all new harness with new left and right hand controls and a new ignition switch and after about 2 years the thing was becoming hard to start so much I had to resort to starter fluid. After doing a coil relay mod, it starts instantly.

I would just solder them directly and cover with heat shrink

I didn't want to solder them on until I get my next project underway (which will prolly be in a month or so). I got me a SH775 and need to figure out where there is room for it.

Well, here's my final numbers after cleaning and soldering the "T" connection deep inside the wiring harness:

Voltage @ Battery....R/R + lead drop.....R/R - lead drop.....Volts @ Coil.
1100rpm = 14.3 volts____0.17 volts_______0.00 volts______13.2 volts
2500rpm = 14.4 volts____0.16 volts_______0.00 volts______13.4 volts
5000rpm = 14.4 volts____0.17 volts_______0.00 volts______13.7 volts.

What an amazing difference! I don't even have the carbs sync'd or adjusted yet - when I press the starter button it starts so quick you can't even hear the starter engage!

[posplayr]

Things are still improving! I read 14.1 volts at idle today !

Now before I re-wrap the wiring harness and run the final numbers I noticed a slight amount of heat (like about body temperature) in the three connectors connecting the stator wires to the regulator. These are (aluminum?) bullet connectors. Is this okay, or should I switch them over to spade connectors?

(BTW, I picked up a roll of Scotch Professional Grade Super 33+ electrical tape to re-wrap the harness. According to videos on the net this is the hot ticket for building custom wiring harnesses. Supposed to be super strong and strecthy, yet is only .007" thick.)

I would just solder them directly and cover with heat shrink

Whoooie!

Things are still improving! I read 14.1 volts at idle today !

Now before I re-wrap the wiring harness and run the final numbers I noticed a slight amount of heat (like about body temperature) in the three connectors connecting the stator wires to the regulator. These are (aluminum?) bullet connectors. Is this okay, or should I switch them over to spade connectors?

(BTW, I picked up a roll of Scotch Professional Grade Super 33+ electrical tape to re-wrap the harness. According to videos on the net this is the hot ticket for building custom wiring harnesses. Supposed to be super strong and strecthy, yet is only .007" thick.)

[posplayr]

So today I opened up my original wiring harness.

Had to go about 6-7 inches so I had enough room to work on the "T" crimp connection.



Yes sir. Cleaned the bare wires with a Navel Jelly product, keeping it moist/wet for 10 to 15 minutes, then flushing it with Deoxit, dried with compressed air. Then soldering the connection.

While I'm waiting for the solder joint to cool, what do people use to re-warp the harness? And a source?

That factory stuff, after 33 years, was still in nice shape - not hard or brittle, and still very stickey. It had not started to unwrap it self any place.

I had to do a double take here but I think this is saying you can store your bare wire with detox it to prevent oxidation, but before you solder clean off the detox-it with alcohol.

In other words probably best to go in this order

1. Navel jelly
2. Flush with water
3. blow it off with air
4. solder
5. Detox it

http://store.caig.com/s.nl/ctype.KB/it.I/id.313/KB.215/.f

I just used a quality electrical tape similar to the factory. I also have some cloth electrical to wrap that in one spot just to keep the electrical; tape from unwrapping if the glue gets gooey and slips.

These numbers are still high just over what I would call borderline. But obviously you can see it is improving and raising your charging voltage in accordance.There is a "T" inside the harness where the R/R wires enter. You open up the harness about 3-4 inches and you will find a crimp. Clean and solder that as well.

So today I opened up my original wiring harness.

Had to go about 6-7 inches so I had enough room to work on the "T" crimp connection.

Are you chemically cleaning the copper and brass? Just because it looks shines doesn't mean there is no corrosion. 0.1 ohms is a lot if you are running 10-15 amps.

Yes sir. Cleaned the bare wires with a Navel Jelly product, keeping it moist/wet for 10 to 15 minutes, then flushing it with Deoxit, dried with compressed air. Then soldering the connection.

While I'm waiting for the solder joint to cool, what do people use to re-warp the harness? And a source?

That factory stuff, after 33 years, was still in nice shape - not hard or brittle, and still very stickey. It had not started to unwrap it self any place.