1979 GS1000L Help !!!

[Anonymous]

We have a 1979 GS1000L.. that did sit for quite some time... It runs but not well..(we also have a 1980 GS750L) so here are the symptoms.. it runs great when you first start it...as soon as it gets warm it starts popping... it has no nads..(it is a 1000 it should) and by popping...I mean like a popcorn maker...continously !!! Compression tested and getting anywhere from 147 to 150 lbs in EVERY cylender... Took the carbs off and sent them to the shop to be cleaned... it also has new plugs ...So the question is..what to look for next?? any help would be greatly appreachated !!! thanks....

[Anonymous]

new findings.....

We have been reading post and boy...you guys are really good at this stuff... so...my new findings are... if you take the #3 wire off the spark plug...it purrrrs like a kitten..(on three cylenders..yes.. but NO popping !!) so...took the boot off....cut it back and swapped it with another one..and the conclusion is that with all 4 cyl. pluged it..it POPS !! so tell me PLEASE what does this mean???? It is a beautiful day here and would be perfect for RIDING !!! thanks....

[Anonymous]

You could spray the intakes with something that burns (usually acetylene) and see if the bike revs up. If it does then you have an intake leak.

Steve

[earlfor]

DAMMIT! Steve, I dont usually make this kind of reply. BUT, THAT is an irresponsible and dangerous reply to give someone. Please try to use your head and some common sense on at least some occasion. PLEASE!!!!!
yeah right, stand in a cloud of acetylene and strike a match. JFC

Earl

You could spray the intakes with something that burns (usually acetylene) and see if the bike revs up. If it does then you have an intake leak.

Steve

[earlfor]

Re: new findings.....

If removing the number 3 spark plug wire eliminates the popcorn popping, the first thing I would do is check to make sure the correct plugs wires are going to the cylinders. You have two coils. The one on the left side (as you are sitting on the bike) has two plug wires. One of them goes to cylinder #1 and the other wire on the left coil goes to cylinder 4. On the coil on the right side, one wire goes to cylinder 2 and the other goes to cylinder 3. (as you are sitting on the bike, the cylinders are numbered 1, 2,3, and 4 from left to right.)

Absolutely DO NOT spray a cloud of acetylene around the bike and hit the ignition.

Earl

We have been reading post and boy...you guys are really good at this stuff... so...my new findings are... if you take the #3 wire off the spark plug...it purrrrs like a kitten..(on three cylenders..yes.. but NO popping !!) so...took the boot off....cut it back and swapped it with another one..and the conclusion is that with all 4 cyl. pluged it..it POPS !! so tell me PLEASE what does this mean???? It is a beautiful day here and would be perfect for RIDING !!! thanks....

[Anonymous]

thanks for the info but now what???

we did replace all the spark plugs... and Earl, I just went by what you were listing and yes all the wires are going to the right cylinders!!! so now does anyone know what the problem could be??? could it be the coils>>
thanks for the help so far!!! Lori

[earlfor]

Re: thanks for the info but now what???

NO, I dont think its the coils. One cylinder popping doesnt indicate a bad coil, and with your compression readings, its not a valve problem.
Are you sure both 2 and 3 are not popping? What color is the center ceramic on all four plugs? In order 1 through 4 please.
A 79 1000 would have a points ignition system and I'm trying to determine if the problem carries over to an ignition matched pair of cylinders or if it is only one cylinder. It makes a difference as to where you start looking. :-)

Earl

we did replace all the spark plugs... and Earl, I just went by what you were listing and yes all the wires are going to the right cylinders!!! so now does anyone know what the problem could be??? could it be the coils>>
thanks for the help so far!!! Lori

[Anonymous]

more findings

in order the #1 was tan..#2 was black and wet ..#3 was black and shiney.. #4 was tan just like #1 ... so what does this tell me now?? Also..if we have all 4 cyl. going..it pops..if we take the #2 and #3 off then it runs without popping...if we have just the 2 and 3 pluged in with the #1 and #4 off..then it just turns over and soesnt start at all...so what is the next step...a coil or points?????

[earlfor]

Re: more findings

AH HAAAAAAAA!!!! :-) You have just given away the secret. LOL
On the right end of the crankcase are your ignition points. You problem is on cylinders 2 and 3. The pointset on the right side of the breaker plate fires cylinders 2 and 3. Either your points are worn down, or they are out of adjustment. Do you already know how to set the points and timing?
Not a problem if you dont, as I do. :-)

It could be a coil, but we need to rule out points first.

Earl

in order the #1 was tan..#2 was black and wet ..#3 was black and shiney.. #4 was tan just like #1 ... so what does this tell me now?? Also..if we have all 4 cyl. going..it pops..if we take the #2 and #3 off then it runs without popping...if we have just the 2 and 3 pluged in with the #1 and #4 off..then it just turns over and soesnt start at all...so what is the next step...a coil or points?????

[Anonymous]

points....

I am not exactly how to set them...if you wouldn't mind... .. Any help is greatly welcomed.. I was told it was the carbs so spent the money to have them cleaned..grrrr... anyways.. you have NO IDEA how much of a help you have been ...thanks !! Lori

[terrybird]

Ya outa charge by the hour for help like this.

[Anonymous]

SHHHHH...dont tell him that ..lol... atleast til after mine is running...lol .. I see you have an 1980 GS750L...that is our other bike.. (and it doesnt have points!!!) Nice bike..we have had ours sense it was brand new..(1 owner)... have a good night..Lori

[skip]

Earl you sure are good at this stuff! if the points dont straighten the problem it probably could be a weak coil. He had said both 2&3 cylinders were running black plugs. I had one go with similiar symptoms. Maybe he could pour gas all over the bike and if it catches on fire then the problem isn't the tires!JUST KIDDING!

[earlfor]

Re: points....

OK Lori, this is the easy part.

Since the problem is on the 2 and 3 cylinder, we will only adjust and time those.

Take off the round cover on the right end of the crankcase that the points are underneath.

You will see two sets of points. One located at the 9 oclock position and the other located at the 3 oclock position. The 3 oclock set is the set for cylinders 2 and 3. The points are mounted on a circular plate about 6 or 7 inches in diameter and at the 12 oclock position you will see about a 5/8" hole in the plate, That is your timing window. Through that hole you will see another plate behind. On that "behind" plate you will find the timing marks. There are four timing marks on the plate. The one you need for static timing the right hand set of points will have a mark that looks like
F2| The line on the right side of the F2 is the static timing mark for the right pointset

Now, forgetting about the timing marks for a minute. Take a 19 mm wrench and rotate the crankshaft clockwise until the right pointset points are at their widest gap. If you pass the widest gap, just go around again.
When you have the crank turned so the points are at their widest, look at the contacts closely. (the contacts are the small round cylinders on the end of the arm) The mating surfaces should be flat. There should be no ridges or lumps on the surfaces. If there are, file the lumps off.
Now loosen the single screw that holds the pointset and take a feeler guage and set the gap to 14 thousandths. Tighten the screw back down that holds the points.

Take a continuity light and clamp the lead on it to the electrical connector/clip of the black wire on the right pointset. Take a clamp and clamp the probe tip of the continuity light to ground either on the bike or to the battery negative terminal. (this will leave both your hands free rather than trying to hold the light and do three things at once)

Look through the timing window and in alignment with the left edge of the bolt head that is above the window, (12 oclock) you will find a mark on the engine case. That is the static timing mark. Take a 19 mm wrench and rotate the crankshaft clockwise until the plate you will see through the timing window rotates to show F2| The line following F2 must be aligned with the mark on the engine case.. If you do not have a mark on the engine case, align the F2 mark with the left edg of the bolt head located at the 12 oclcock position.
Once you have these two marks aligned, switch on the ignition.
(do NOT start the bike, we just want the ignition switched on)
The continuity light will be on/lighted.
Very lightly press the points together, the light should go out.
If the continuity light is out, you will need to open the points very slightly.
Loosen the screw on the right pointset and lightly tap the points in either direction as needed to get the continuity light to just go out.
Usually I get them close enough that the lightest touch on the points pressing them together with my finger will cause the test light to go out.
The light indicates when the points will "break" and you want that break to occur at the same time the timing marks are aligned .
Once you have the points set so the light flickers out, tighten the pointset mounting screw down.

Youre done. Remove the continuity light and you should be able to start the bike.

(If you do not have a continuity light, you can make one with a 12 volt bulb and a couple wires)

Let me know how things work out. :-)

Earl

I am not exactly how to set them...if you wouldn't mind... .. Any help is greatly welcomed.. I was told it was the carbs so spent the money to have them cleaned..grrrr... anyways.. you have NO IDEA how much of a help you have been ...thanks !! Lori

[earlfor]

We, we aint outta the woods yet. :-) :-)

Earl

Ya outa charge by the hour for help like this.