Success!!

[jasper]

OMG

Three weeks later and my 1980 GS550E (Canada Only) is running...almost perfectly. Turned out to be a bit of a laundry list of issues.

1) Weak spark - I was pretty sure my igniter was toasted so I bought a Dynatech DS3-2.It was pretty straightforward to install....had to file down the spacer is all. Now I have a very strong spark.

2) Timing is weird. At 2500 rpm, the F mark is well away and to the left of the timing mark. I filed out the slots to give me some more rotation, and now at least the I mark is at the timing mark at idle, but the F mark is still way way to the left at either idle or at 2500 rpm. Bike runs ok but I can't help but think it could be better. Am I doing this right?

3) Took an extra day of screwing around because even with the super strong spark it still would not run...until I sprayed in the starter fluid and sure enough it ran just fine for s few seconds anyway.

Of course it was the damned petcock giving me grief. The 1980 GS550E has a petcock with only two positions. RUN and RES. No PRI position. Finally I got my hand pump and opened the valve and it ran good...for a while.

Finally I put the valve in the RES position, and with the hand pump to keep the valve open the bike runs like a champ. A good two hours on the road and it didn't bog or gasp once.

At the moment I have the hand pump zip strapped to my handle bars and I give it the odd squeeze to make sure the petcock stays open (the line from the carbs is plugged with a golf tee. Eventually I will try it hooked back up to the carbs, I just wanted to prove it would run, and it did, but only in the RES position, not in the RUN position.

I'm in the market for a new petcock with a PRI position though....and can anyone offer up some advice on the timing question.

Hey - thanks for the support from those of you who took the time to offer advice and post procedures on-line. I could not have done this without you.

[SqDancerLynn1]

Another one saved. Good job..

[mike_of_bbg]

2) Timing is weird. At 2500 rpm, the F mark is well away and to the left of the timing mark. I filed out the slots to give me some more rotation, and now at least the I mark is at the timing mark at idle, but the F mark is still way way to the left at either idle or at 2500 rpm. Bike runs ok but I can't help but think it could be better. Am I doing this right?

Is the spark advancing from idle -> 2.5k RPM? At what speed is your bike idling? You mentioned thinning the spacer - I assume then you've verified that the rotor is free to advance independently of the crank? Should be loose. You may need to clean your mechanical advance mech.

The "F" mark should be to the left when running @ 2500. Of course you should be up against the 1,4 mark then. And you should be right about on F at normal idle (~1100 RPM). Mine was timed right near the end of the slots. I'll attach pic below. BTW, note you might be able to get a little more adjustment out of the pickups themselves. IIRC they're slightly slotted.

T mark - TDC, used for CAM timing only
F mark - timed @ idle
1.4 mark - timed @ 2500 RPM +

[jasper]

Hi Mike - Glad you chimed in seeing as you're *the* guy with the same setup as me.

1) The weights move freely, the spacer has a few thou of play, the ignition visibly advances as I increase the speed of the engine. No issues there.

2) The bike is idling about 1400 or so. I'll be able to fine tune that once I know my timing is right.

3) My timing at the moment is set up at the extreme opposite of yours. ie my plate is rotated as far counter clockwise as it will go rather than all the way clockwise like yours. I even extended my slot so it would turn *farther* counter clockwise. Obviously I will have to revisit this.

4) I thought the F meant Full as in full advance at 2500 rpm. I'm not doubting you per se but...are you sure it should be on F at idle?

Thanks for the diagram - I will compare this to my actual.

For what it's worth, the bike screams on up to redline without any hesitation or stumble so I don't think I'm way out.

[jasper]

Added note -

Now that I've had a chance to think, if you are correct then I am at full advance at idle...which wouldn't affect my performance at high engine speeds but could explain my slightly sensitive idle.

It's coming in to focus nicely.

****

Since I'm in the process of putting my stupidity on display, I've also just realized that maybe my bike would only run with the petcock in the RES position......because I was low on fuel !!!!

That would explain a lot eh?

[mike_of_bbg]

1400 is high for idle - 1100 +/- 100 RPM is spec. So you might be advancing a bit at idle already. Your advancer springs might also be tired and not getting you the full advance range.

Helpful info from the service manual attached.

[Steve]

Of course it was the damned petcock giving me grief. The 1980 GS550E has a petcock with only two positions. RUN and RES. No PRI position. Finally I got my hand pump and opened the valve and it ran good...for a while.

Are you SURE what the two positions are?

I was under the impression that your two positions were RUN and PRI.

As far as I know, you have no REServe.

The PRI function is a little different than most, though, you need to apply a little vacuum, then it will stay ON until switched to RUN.
The RUN position relies on having vacuum to open, then closes when the vacuum is removed.

.

[jasper]

Steve...dude.

The two poistions are ON and RES. There is no PRI position. Trust me on this.

Better yet, refer to page 343 of the 77-82 service manual from BassClifs site (see attached). This is a Canada only 1980 only design. It's just terrible.

[jasper]

Oops - that's not very legible is it?

Try this one please

[jasper]

1400 is high for idle - 1100 +/- 100 RPM is spec. So you might be advancing a bit at idle already. Your advancer springs might also be tired and not getting you the full advance range.

Helpful info from the service manual attached.

That's excellent Mike. Thx.

[Big T]

4) I thought the F meant Full as in full advance at 2500 rpm. I'm not doubting you per se but...are you sure it should be on F at idle?

F is the Fire mark at idle

If you're using a timing light (which you should be) set the F mark at idle (1100 rpm).

Then rev it slowly and watch it advance to the advance mark. Have a helper call out the rpms, you can then determine if it's advancing too soon.

[Steve]

Steve...dude.

The two poistions are ON and RES. There is no PRI position. Trust me on this.

OK, my bad.

I saw that it was an '80 and presumed that it was the "dreaded '80 petcock" that everyone talks about.

They have RUN and PRI, but need a screwdriver to change it. I see that yours is considerably different.

.

[jasper]

OK, my bad.

I saw that it was an '80 and presumed that it was the "dreaded '80 petcock" that everyone talks about.

They have RUN and PRI, but need a screwdriver to change it. I see that yours is considerably different.

.

It's cool. I wouldn't believe that something so poorly designed would ever make it into production either.

As "dreaded" as the standard 1980 petcock may be...I think mine is worse.

[Suzuki_Don]

[QUOTE=mike_of_bbg;1461817] Your advancer springs might also be tired and not getting you the full advance range.[QUOTE]

Mike if the springs were tired or weak wouldn't that allow the bob weights to throw out more easily and allow full advance more quickly. What do you think.

[jasper]

Well ain't that a thing!

After my successful ride the other night I thought it would only get better once I set my timing correctly. Yeah - not so much.

This evening I set up my timing light and turned my base plate clockwise to about the same position that Mike shows in his photograph. Prior to that I had the plate turned all the way counterclockwise.

Sure enough, at the new position, the F mark lined up with the timing mark at 1100 rpm. At 2500 rpm, the line adjacent to the 4 was at the timing mark. Perfect timing.

Well, it ran ok, but not great, and it wasn't too long before it bogged, stalled, and would not restart. WTF - this was my problem a month and a half ago!

I went and got a screwdriver, returned the base plate to the far counterclockwise position (you can barely even see the timing mark through the little circle window anymore) and the bike fired up and purred like a kitten. OK more like a cat and it's more of a raspy wail on account of the muffler being a bit beat up but the point is....it runs great with the timing way way retarded according to the timing marks and with the timing set according to the manual the bike runs about 15 minutes and then bogs stalls and won't restart...oh yeah and backfired when you try to roll start it.

On another note...the baseplate and cover are super hot. How normal is this? In fact the engine case in that area is equally hot so maybe that's normal but for a while I was thinking maybe the heat was killing my igniter.

Comments anyone??