79 gs850 won't start

[syren]

Bought the bike a month ago, after changing plugs and adjusting choke, it would start for a few seconds then sputter out. After spraying with carb cleaner it would turn on once every 10 tries or so and idle without issue when it was on, but when I would give it throttle it would die.I took the carbs off and took them apart and soaked in carb cleaner, replaced orings and put them back on the bike (jets were clogged bad). Now the bike still makes that noise like it wants to turn over but won't. I get that WAH WAH WAH WAH WAH over and over but it doesn't turn, doesn't even start for a few seconds now like it would one out of ten times before. Battery is fully charged as well. Any suggestions on what to do next? There is fuel getting to the carbs, the float bowls were full.

[Nessism]

Did you check spark? Lay a plug along side the engine and crank. If the first one sparks, check the others.

[Steve]

How long did you soak the carbs? If they looked as bad as you suggested, a full 24-hour soak would be in order.

Also, have you checked the valve adjustment? Tight valves are a typical cause of not starting well when cold.

.

[BassCliff]

Hi Mr. syren,

Let me reiterate some words from a very wise GS850 rider:

Every GS850 [and most other models] has (or had) a set of well-known issues that MUST be addressed before you have a solid baseline for further troubleshooting. It's a vintage bike, and it's quite common (as in, every single GS850 I have had contact with) that there are multiple problems that have crept up and slowly gotten worse over the years. It's not like a newer vehicle, where there's generally one problem at a time.

These common issues are:

1. Intake O-rings (install NEW OEM or Viton only - common nitrile O-rings will quickly deteriorate from heat)
2. Intake Boots (install NEW -- these cannot be repaired)
3. Valve clearances (more important than most people think)
4. Carb/airbox boots
5. Airbox sealing
6. Air filter sealing
7. Petcock (install a NEW one)
8. On '79 models, install new points or Dyna electronic ignition (or at least verify that the old points are working correctly)
9. On all models, it's fairly common to have problems with the spark plug caps. These are $3 or $4 each, and often worth replacing if you're keeping the stock coils/wires.
10. Stock exhaust with NO leaks or holes -- good seals at the head and at the junctions underneath.

Click here for the carb rebuild series. Read it, learn it, live it, love it.

See my website for valve clearance and other information. Until you've addressed all the above issues, you'll be chasing your tail. There are no shortcuts or silver bullets.

Thank you for your indulgence,

BassCliff

[syren]

Basscliff, I have been working from that list and I have done everything except checked valves and install new points. I will check for spark today. I take out a spark plug, crank it and look inside?

[Nessism]

Basscliff, I have been working from that list and I have done everything except checked valves and install new points. I will check for spark today. I take out a spark plug, crank it and look inside?

Spark plug must be installed into the socket, and the body of the plug (metal part) needs to be grounded against the engine. If the plugs are old, just replace them so you know they are fresh. Also, don't touch the metal portion of the plug when cranking the engine or you WILL get shocked. You've been warned!

[mighty13d]

yes, plug the spark plug into the wire and lay it on the side of the engine. If your life is dull, hold onto the plug. If you don't need to be lifted... just watch the spark without holding it! lol

AKA: DO NOT hold the plug, and try to do it in the shade to it's a little easier to see if you're getting spark or not.

[BassCliff]

Basscliff, I have been working from that list and I have done everything except checked valves and install new points. I will check for spark today. I take out a spark plug, crank it and look inside?

Hi Mr. syren,

My post was kind of snooty. I apologize. I know you want to work through all the issues on your bike and get it running great. Keep up the good work and please keep us informed.


Thank you for your indulgence,

BassCliff

[SqDancerLynn1]

What helps sometimes with the spark is to unscrew the plug cap and cutthe wire back a 1/4" and reinstall. Also make sure you have 12 v on the coils

[Suzuki_Don]

What helps sometimes with the spark is to unscrew the plug cap and cutthe wire back a 1/4" and reinstall. Also make sure you have 12 v on the coils

LYNNE you're so dang down to earth. You come up with the most common sense ideas.

[silverhorse47]

You might also crank the engine a bit before you remove a plug. If it's wet when you get it out, you'll know gas is getting to the plug.
S.

[gustovh]

Your battery may seem charged but could be just weak enough to turn over the engine but not enough to produce the spark needed. I chased that one for a while untill I bought a new one and game over. just a thought.
V

[syren]

I will try the spark plug idea when I get home. If I don't see a spark, what do you think it is? Contacts?

[syren]

OK So I am at home now and still a little confused on how to test this spark. I leave the spark plug screwed in and take the other end of the spark plug wire and touch it to the metal part of the engine and look for spark? Or do I just take the wire off and watch the spark plug? I really appreciate all the help and sorry for sounding like such a newbie

[syren]

ALSO where is my kill switch? Do i only need to hold in the clutch and make sure the engine is set to on? Is there something else I need to check besides fueses (all of which are new) like a toggle switch?