1980 GS550L Rebuild Thread

[gs550marc]

Hello.

Some of you may (recently) know of me. I am the one who was headed towards Canada on my GS550 (from Brooklyn, NY) with a friend on his intruder. Long story short, the bike would lose power intermittently on the highway. A mechanic was able to see it in Massachusetts and I made it as far as New Hampshire before I called it quits and put it on a U-Haul Trailer home. The suspects could be signal generator, loose connections, not getting enough fuel at times. This issue has never happened to my bike before. I've had it for a year now.

It has since ran OK sometimes, sometimes not. It recently left me stranded a few blocks away from the garage where I store it. After some playing around with some wires and some help, we were able to get it going just to get it back (wouldn't hold it's idle or rev past 4k).

Anyways, I've decided with this second week off from work (should've been in Nova Scotia by now), I'd strip the bike down, learn it better than I have and put it back together while replacing anything that needs to be replaced, adjusting what needs to be adjusted and maintaining what needs to be maintained.

Things I've already completed prior (within past 7 months):

-Full carb clean and rebuild
-New Ignition Coils
-Gas Tank fully cleaned out from the inside
-New Petcock
-New Spark Plugs (today)
-Valve Clearance checked (today)! (all are within spec)!
-Replacing Valve cover gasket
-New Battery
-New Clutch and Throttle Cable

I currently have everything but the engine/transmission/wheels/brakes off the bike.

Any input, suggestions on what little things to replace (I'm ordering new o-rings for the intake boots today) would be greatly appreciated.

[hikermikem]

Hi Marc,

What type of new coils did you install? Dyna green ones (3 ohm)?

When I put a set of those on my '85 550L, it was a VERY tight fit under there. Seems those 550L bikes (with those smaller tanks) have very little room under the tank to fit the coils - it's easy to accidently ground out a lead against the frame.

You could actually hear mine snapping as they intermittently shorted out. Raise the tank up a little and look at night & see if there's any sparks.

[gs550marc]

I installed OEM coils. The older ones we're faulty upon testing several months ago.

I can get a bit weary about putting aftermarket parts to the bike, although the idea of a Dyna Ignition entices me if my problem is in fact the signal generator ($200-something) on bike bandits for a replacement.

[hikermikem]

Z1 is the place for those, although I'm not sure they are offered for the 550.

[gs550marc]

Pictures!

Finally Created a Photobucket account.

What I have done in the past day:

-Tightened Chain
-Cleaned out lots of gunk behind the sprocket cover
-Cleaned/Sanded/Greased up all grounds and wire ends (still going through all of them to make sure none are frayed)
-Loosened up all intake boots! (Waiting on new o-rings from BB)
-Took off the rear mud guard (chrome) and I'm loving the look of it
-Took a .0000 Brillo to my exhaust pipes to bring the chrome (worked better than I expected).

Someone at my garage offered me airpods for $2 a pop. I'm contemplating them but I believe it's only for the aesthetics. I'm not really interested in re jetting my carbs as they are running very well. Looks like the stock airbox setup will be cleaned up and reinstalled.

Am I missing any vital checks at this point?

I will be attempting the fork seals and brake pad checks tomorrow.

Anyways, pictures:


First tow of my trip


Stripped down with wires labeled




Carbs, batt, etc. off


The things I found in here...


Exhaust off, little parts in Hefty Bags.

[Missile99]

Hi gs550marc,

I read through some of your older posts and see your frustrations but it looks like you'll be good in no time. I have a few questions and suggestions though:

How many miles have you put on this thing and how many tanks of gas have you burned through? When I was running regular 10% ethanol gas it turned bad in 3 weeks while working on other things. It smelled like I poured lacquer thinner into the gas and it was a dark color. Bike ran like garbage of course. Now I run 90 recreational (no ethanol) but still drain the carbs if she's going to sit for a while. I also tend to drain the tank and start fresh if older than 5 weeks.

When the bike was running how well did it perform? Up to redline no problem?

I like that you're going through the wiring. That'll save many headaches. How was your spark intensity? If you're using stock coils did you snip the ends to expose clean wire before screwing in the new ends?

If there's a rough idle try the highest rpm method if not done already. This should smooth things out good.

It doesn't look like you have a component problem (i.e. signal generator, ignitor, coils). I installed a Dyna-S when ignitor died and green coils after being frustrated with the thin, weak orange/blue spark. Now with these 3 ohm greens there is a thick white/blue spark.
Save your money and down time if you can though. The stock stuff works good enough for a long time.

[gs550marc]

Hey Missile99,

I have just over 20,000 miles on the GS and yes when she runs well, she runs very well. Pulls very strong close to the redline in all gears (haven't hit redline in 5th/6th). I've also always used 87 and never thought about the whole 10% ethanol and how it affects my an older engine. Any other opinions out there about this? I truly don't believe my issue is fuel related though. What I will do is switch to a clear fuel line (no filter) to be able to make sure fuel is flowing whenever I need to.

Spark is great when I test it, the coils are strong (as they should be since they are new).

The rough idle only happens when I'd get that power loss. If the power happens to "come back" which happens randomly, I will idle just fine.

Any yes, I'm going to do everything I can to keep things stock although a set of air pods just offered to me is looking very enticing.

Anyways, waiting on a BikeBandit shipment to install O-rings before I can put the carbs back on and get it running again.

Thanks for the input

[Missile99]

Okay. I missed the fact of new coils. Cool. Well, with your carbs clean and set properly, and airbox/intake all sealed up nicely it makes me think there is an intermittent short in wiring. When your bike dies, do your dash lights or headlight go dim or flicker?

Did you clear up that melted spot behind fuse box I read earlier?
Have you checked all ignition related wires? Start at the signal generator and make sure the wires that lead from it have no broken insulation from rubbing the frame/oil pan or exhaust. Another suspect is the connector to coils in the headlight bucket. If it won't come apart easily or smells burnt start fresh. If it's bad replace it with either stock looking connectors or separate insulated crimp ones.

The pods might seem tempting but not worth the tuning headache you can create. It would be nice to not fight with squeezing the carbs in but if they're clean and sealed you shouldn't have to remove them for a long time.

[gs550marc]

I would notice that the neutral light would flicker, yes.

The melted spot turn out to be some quick fix someone must've done on the box before, but I assured the connection is good and added some dy-grease to it.

Yea, I think I'll leave the creativity to a new tail/signal lights in the back.

I'll be finishing up the wiring harness clean up today in this 92 degree day.

[hikermikem]

did you ever verify the fuel tank was venting correctly? Did you (or a PO) line the when it was cleaned out? Make sure the little vent hole in the filler tube is clear...

Somtthing to try next time you lose power, pull over & pop the fuel cap & listen for a "sucking' sound.

[Missile99]

I would notice that the neutral light would flicker, yes.

Could have been a charging circuit or ignition short. Hopefully going through all of the connections that affect the operation of the bike will cure your problem. It could be one of them is creating too much resistance. Replace any questionable connector.

The melted spot turn out to be some quick fix someone must've done on the box before, but I assured the connection is good and added some dy-grease to it.

Awesome!!!!

Yea, I think I'll leave the creativity to a new tail/signal lights in the back.

You can scratch the extra strength aspirin or ibuprofen off the list.

I'll be finishing up the wiring harness clean up today in this 92 degree day.

Can you believe it's hotter there than here? This isn't supposed to happen. My family up there told me they're melting.

Keep us posted. Hope it runs perfectly.

[gs550marc]

So today I stripped off all the old, old electrical tape from every harness I had and checked every wire for fray, nicks, cuts, etc. After opening up the harness that goes into the headlamp, a good amount of water just poured right out; I did not like that. Anyways, I retaped everything super tight and it all looks new and shiny. Every male/female end got a touch of di-grease and I've put the airbox, battery box, fuse box, starter relay, etc. back on, cleaning out all the grounds and putting the di-grease on it.

[gs550marc]

Just thought I'd share the garage I store/work on the bike in:

[gs550marc]

I read this elsewhere as well. I have since taken compressed air and blasted through all the vents, lines to clean everything out.

I'm getting excited to fire it back up and test drive a "cleaner" GS.

did you ever verify the fuel tank was venting correctly? Did you (or a PO) line the when it was cleaned out? Make sure the little vent hole in the filler tube is clear...

Somtthing to try next time you lose power, pull over & pop the fuel cap & listen for a "sucking' sound.

[gs550marc]

New Windshield

New windshield came in after the first one that was shipped looked to have been kicked around by UPS.

This thing is HUGE: