79 GS550: Hesitiation, then dies

[Pendulum]

I picked up a 79 GS550 to get around on and it's been pretty neglected from what I can tell...

We have to do emissions here in AZ, and it failed with about 2x the limit on HC so I put some new plugs in last night. In the course of doing that, I did the following:

* Plug wires were cracked, so I pulled the tank to see what coils were there to order replacements
* Changed plugs, with 0.32 gap. Used NGK BR8ES
* Pulled air filter and cleaned it. It had so much oil it would stick to my hands. Normal?
* Attempted to remove air box, before realizing the filter was accessed under the seat

I put everything back together, and went for a spin around the block. All seemed well, but it did backfire. Didn't think anything of it really since it's done it since I bought it.

This morning I tried to take it to work and I'd get about a 1/4 mile and start having hesitation. Shortly after would come drastic power loss, eventually to the point of being full throttle and still decelerating. The 3rd time it died, I gave up and called a taxi. A co-worker took me back to the bike at lunch and it did it again.

I've verified that all of the intake boots from the airbox to carbs are tight
I double checked the air filter and it looks fine
Checked my plug wires, and they're on tight and in the right order... But the boots are cracked.

I just need to get this thing rideable since it's my only transportation. I plan on going through the whole thing and sorting it all out once it passes emissions and is registered.

[BassCliff]

Greetings and Salutations!!

Hi Mr. Pendulum,

You've got a neglected, possibly abused, 30 year old motorcycle that needs a fair amount of maintenance and TLC. The lists in your "mega-welcome" are the steps necessary to restore your bike to a safe, reliable condition. Clean the carbs, adjust the valves, seal the air intake system, install new tires, fix the brakes, change all the fluids, install new fork seals, new sprockets, new chain, etc, etc, etc. The air filter should be cleaned and then a very light mist of oil applied. Many members use the green 3 ohm Dynatek coils, but coils rarely go bad. Do some troubleshooting before you start throwing parts at your bike. You'd be surprised how much the emissions will clean up just by changing the oil.

Anyway, let me dump a TON if information on you and share some GS lovin'.

I just stopped by to welcome you to the forum in my own, special way.

If there's anything you'd like to know about the Suzuki GS model bikes, and most others actually, you've come to the right place. There's a lot of knowledge and experience here in the community. Come on in and let me say "HOoooowwwDY!"....

Here is your very own magical, mystical, mythical, mind-expanding "mega-welcome". Please take notice of the "Top 10 Common Issues", "Top 15 Tips For GS Happiness", the Carb Cleanup Series, and the Stator Papers. All of these tasks must be addressed in order to have a safe, reliable machine. Now let me roll out the welcome mat for you...



Please click here for your mega-welcome, chock full of tips, suggestions, links to vendors, and other information. Then feel free to visit my little BikeCliff website where I've been collecting the wisdom of this generous community. Don't forget, we like pictures! Not you, your bike!

Thanks for joining us. Keep us informed.

Thank you for your indulgence,

BassCliff

[Pendulum]

Thanks for the welcome sir I've read through your site, and a few that you've linked, and all that stuff is on my long list of things to do. I think my bookmarks folder tripled in size after finding your site.

Any idea what could be causing my specific issue? Like I said, I plan on getting all that stuff done but I need to get this thing sorted out ASAP. Gotta get to work!

[BassCliff]

Hi,

Any idea what could be causing my specific issue?

I'm sure there are several things causing your specific issue.

READ ME.

Everything starts with clean carbs, well-adjusted valves, and an air intake system with no leaks. Take no shortcuts or you will be frustrated.

Thank you for your indulgence,

BassCliff

[Pendulum]

Well considering it ran last night, I guess I'll just go through everything I touched. Like I said, this is my only way to/from work. All the maintenance was going to be done on the weekends, after I got it registered.

[Big T]

Does you bike still have points?

If so, sudden loss of power generally is the result of timing change

Replace points and condensors with a Dyna S

[BassCliff]

Hi,

Does you bike still have points?

If so, sudden loss of power generally is the result of timing change

Replace points and condensors with a Dyna S

There you go. I never think of these things, having a bike with electronic ignition.

It could be that your points and condensers just need to be replaced. But everything else on the maintenance lists is important too, especially if you don't know the maintenance history of the bike.


Thank you for your indulgence,

BassCliff

[cowboyup3371]

Clean those carbs ASAP or you'll be without wheels for a long time fighting with it.

[Pendulum]

I should have mentioned the bike is running a Dyna III with 8 ohm coils. I'm on my way to pick the bike up and get it home now. This has been a rough month for me and this is not helping : /

[Pendulum]

Well I feel like a dummy... One of the plug wires wasn't pushed on all the way. Now that that is sorted, the bike idles much better than before I did the plugs. I've got the carb rebuild kits and a fuel filter on their way from Z1, should be here Tuesday-ish. I'll order the new coils on the 1st. Oil change Saturday morning.

I've seen conflicting info on the the fuel filter. Should I be running one or not?

[tkent02]

I've seen conflicting info on the the fuel filter. Should I be running one or not?

Hard to say, I can't see the inside of your float bowls or gas tank from here.
But you really need to read Cliff's stuff and do it.
Why would you be buying coils, carb kits, and filters when the carburetors are not even cleaned yet?
Read Cliff's stuff.

[Pendulum]

Hard to say, I can't see the inside of your float bowls or gas tank from here.
But you really need to read Cliff's stuff and do it.
Why would you be buying coils, carb kits, and filters when the carburetors are not even cleaned yet?
Read Cliff's stuff.

I figure if I'm going to pull the carbs off, I may as well just do the work. Like I said, the bike hasn't been maintained well so I'm sure it could use it. And as far as the coils, the boots are cracked, like I've mentioned a couple times.

[tkent02]

Whatever .

[BassCliff]

Hi,

The aftermarket "carb kits" are not highly recommended. Instead, completely disassemble the carbs and dip the carb bodies and metal parts for up to 24 hours. Re-use all of the jets and other metal bits. Replace only what is worn or broken with OEM parts. Reassemble the carbs with an O-ring kit from http://cycleorings.com.

Please read the "mega-welcome" and follow the links to the "how to" guides so that you know the right way to clean and rebuild your carbs. These are tried and true, time-tested methods. Don't take short cuts.


Thank you for your indulgence,

BassCliff

[MisterCinders]

Listen to BassCliff. He is wise.

Don't forget to pick up some fresh carb gaskets on top of the o-rings. They are the only part of those kits worth getting. Buy them separately from Z1 for much less than the useless kits.