New coils - still lose 1&4 after bike is hot

[Fergie]

Hey all,

I've received some great help behind the scenes via PM, but need some more help as I am lost as to what to do.

I bought the bike a week ago, and the seller disclosed that the #4 cylinder would cut out sometimes, but that it was most likely the coils.

I brought it home and rode it for a bit, then #4 cut out, but I was still able to get it home.

I rode it to work in the morning, but had to trailer it home for similar reasons as above.

I pulled the plug, put it in the HT end, and grounded it to the engine, and it wasnt sparking, same for cylinder #1....new coils are needed.

This evening, I replace the old coils and wires with a new set from Accel, the 140403 version, and reassembled everything. I checked for spark at each cylinder before I started the bike, and all was good.

I took if for a drive, and the power was there throughout the entire ride. I parked it, and let it sit for about 1.5 hours. I then went to start it again, and no spark to #1 and #4.

So, what gives? I'm lost as to what to try next and need some help. It runs fine when cold, but as soon as it is warm, it dies and loses spark to #1 and #4(same symptoms with old and new coils).

The seller previously replaced the stator, and the battery is in good shape. The carbs have been synced, but I did bring the bike from 2800 to 7000, so I'm not sure if it needs to be jetted for this altitude.

The wiring is a rat's nest that needs addressing.

Please help!

Thanks, and check the pictures for the wiring situation.

Gavin

 

[Guest]

There's more to the ignition than the coils.
Ignitor and crank trigger.

 

[Fergie]

The bike is a 1978 GS750E...might affect responses.

 

[rapidray]

If it is just 1 & 4, I would suspect the crank trigger since you already changed the coils. Ray.

 

[Guest]

Are you running the stock points?

 

[Danjal]

Are you running the stock points?

Chef beat me to it. Pull your points cover once and check it.

 

[Fergie]

I do not know if they are stock point or not; I'm so new to bikes that I don't know where to look for the point either!

I'll check the manual and take a look tomorrow, but a brief description would go along ways for me.

Thanks.

 

[Guest]

Right front round cover is the ignition cover.
I bet this is where your problem lies.
The manual will be your blessing.

 

[BassCliff]

Hi,

Here you see the right side of the engine with the ignition cover off. Yours will probably look different because mine has the stock electronic ignition. Your bike had points and condensers in the stock configuration.

Thank you for your indulgence,

BassCliff

 

[posplayr]

My first question is what new devices were added? What is that thing with the heat sink near the battery. All those crinp on power connections (I counted 3 i think) are really bad.

There is also a bug roll of electrical tape with twist on electrical connections. Those are not as scary but kinda out of place.

As has been mentioned there are other things required to fire 1-4 than just the coil.

 

[salty_monk]

If I had to take a guess I would say that thing that looks like it's on a heatsink is some kind of relay as it looks like it has depth....

The crimp on connectors (especially the read wire in the later pic) looks like it could be for a Dyna S...

The twist connectors look like they are on the stator outputs to me....

 

[posplayr]

If
The crimp on connectors (especially the read wire in the later pic) looks like it could be for a Dyna S...

Is a Dyna related to the Coils? :-\\\


I looked up the part it is an automotive relay. So it is shock mounted. The big inline fuse holder is also part of an apparentl coil relay mod. What I dont like is that he is using one one of those crimp connectors for that. It is not the pronlem (yet).

Although the color coding leaves something to be desired, more than likely they are power connection crimps.

 

[Fergie]

I personally have not added any items, aside from the new coils. The previous owner had not mentioned any conversions or additions to the bike, but had said he had replaced the stator at one point.

The wiring looks horrid to me, and needs to be fixed at a point near in the future, but I'm leaving it be right now until I trouble shoot it correctly.

I'll get into the points and condensers this evening, and reference my manual, and troubleshoot it per the various write-ups.

I appreciate all the help and will report back later with what I have done, found, and maybe some more pics for flare.

Thanks all.

 

[posplayr]

I personally have not added any items, aside from the new coils. The previous owner had not mentioned any conversions or additions to the bike, but had said he had replaced the stator at one point.

The wiring looks horrid to me, and needs to be fixed at a point near in the future, but I'm leaving it be right now until I trouble shoot it correctly.

I'll get into the points and condensers this evening, and reference my manual, and troubleshoot it per the various write-ups.

I appreciate all the help and will report back later with what I have done, found, and maybe some more pics for flare.

Thanks all.

Well the bike HAS BEEN modified with at least

• the coil relay mod and
• perhaps a Dyna S.

The fact that there are mods DOES NOT directly point YOUR CURRENT problem being in the wiring. However YES there should be (at some point)some changes to the wiring; specifically the removal of those "crimp on" connections for power distribution.

The most likely issue will be found underneath your ignition cover. Whether that is points or DynaS.

 

[Fergie]

Well the bike HAS BEEN modified with at least

• the coil relay mod and
• perhaps a Dyna S.

The fact that there are mods DOES NOT directly point YOUR CURRENT problem being in the wiring. However YES there should be (at some point)some changes to the wiring; specifically the removal of those "crimp on" connections for power distribution.

The most likely issue will be found underneath your ignition cover. Whether that is points or DynaS.

I agree on the wiring situation.

For my own edification, is the relay mounted near the battery in my first picture the "Coil Relay Mod"?

 

[rapidray]

I keep forgetting these things came with points & condensers! YUCK!!! Ray.

 

[posplayr]

I agree on the wiring situation.

For my own edification, is the relay mounted near the battery in my first picture the "Coil Relay Mod"?

Yes, that is what it appears to be. The is a crimp connection near the solenoid to get battery power that also runs through that fuse holder near the relay. The wires to control the relay and send switched power to the coils are all wired in.
My suggestion with that is to remove the crimp on connection and put a ring lug on it. Then attach it to the solenoid or battery directly. Otherwise it looks pretty good.

 

[Fergie]

Yes, that is what it appears to be. The is a crimp connection near the solenoid to get battery power that also runs through that fuse holder near the relay. The wires to control the relay and send switched power to the coils are all wired in.
My suggestion with that is to remove the crimp on connection and put a ring lug on it. Then attach it to the solenoid or battery directly. Otherwise it looks pretty good.

I'll try that out; thank you!

On another note, I've been researching and reading on points and condensers and such. I get how they function now, and the location on the bike.

After troubleshooting and checking to see what the exact issue is, and making the assumption that it is the points and condenser, I'm thinking that I'll be better off with a Dyna unit. The is all predicated by what I find under the cover.

 

[tkent02]

I'll try that out; thank you!

On another note, I've been researching and reading on points and condensers and such. I get how they function now, and the location on the bike.

After troubleshooting and checking to see what the exact issue is, and making the assumption that it is the points and condenser, I'm thinking that I'll be better off with a Dyna unit. The is all predicated by what I find under the cover.

Points are great, because they are simple. You look, you see what is wrong, you fix it.
Easy stuff.

 

[salty_monk]

These are a good alternative to those crimp connectors....

Sold online or at Napa even.

http://www.posi-lock.com/posiplug.html