Help...79 GS1000 runs like crap

[Def]

Hey

My old GS1000 has been running excellent for the past 2 years up until a few days ago. The bike is ridden regularly year round. I was riding along the other day and the bike started missing under load. I made it home...barely....then decided to take it around the block the next day to see if the bike still ran poorly...yup no change (don't know why there would be any change as I hadn't done anything to it yet, lol).

I decided to pull the carbs , cleaned the air cleaner, checked the airbox for blockages, checked the airbox for leaks, disassembled the carbs and cleaned all the orifices and passageways (the carbs were clean prior to cleaning but did it anyway) I pulled the valve cover off to ensure the camchain didn't jump a tooth but everything lined up perfectly, decided to check valve clearances, everything was perfect as well. Reassembled the carbs back to the way I found them, replaced the sparkplugs, points, condensers then synched the carbs and fired up the bike. Choke works the way it should, bike idles but with a very slight miss, no hangup of idle when blipping the throttle, takes off nicely at very low rpm but when fuel is administered, the bike misses like crazy all the way up the rev line. (I also pulled the tank and cleaned it out but it was clean as well). The petcock filter was also clean.

The electrical also checks out as there is spark at all sparkplugs, one coil shows 4.3k ohms the other 4.8k ohms.
I've noticed that the points on the 1-4 side has a much fatter spark than 2-3 side.
I've changed the rectifier to the sh775, new battery last year, stator appears good. (I just checked it out cuz I just changed starter clutch assembly).

Any other suggestions? I'm at a loss on this one.

 

[Grimly]

Sparking at the points is not a good thing. If the condensers are in good condition there should be next to no point sparking.
I'd not be surprised if the condensers are duff. Not unknown for New Old Stock or pattern parts to be dead in the box.

 

[Guest]

If it's a daily rider you would be well served to switch out the points for a Dyna ignition. Also check the secondary on the coils. Sounds like an electrical issue, I'm guessing related to the points/condensers.

 

[tom203]

Yes, sounds electrical...try new spark plug caps ,one might be corroded ..about $5 each

 

[Def]

Thanks for the input. Yes, I forgot to mention I changed the plug caps as well. Where do I measure the secondaries on the coils? at the points? What reading is normal? Also, if the coils are good, is it advisable to change them out anyway when converting to Dyna ignition? Must it be dynacoils or are their others that bolt right in to where the originals are placed on the frame that are just as good or better? Sorry for all the questions but I might as well do things right.

 

[Nessism]

How long since the last valve adjustment?

 

[Def]

Last valve adjustment was 4 days ago and not one valve had moved... not even a bit. Kinda happy about that.
I may have found the problem although I think I should still install a dyna ignition. One of the new condensers was bad. I swapped it out with another one and the point spark on both sides are nice and small and even. I re-adjusted the timing as well as the 1-4 side was under advanced. Now the bike seems to run better but it's raining out so I'll take a test ride once it stops.
I'll post my results here.

 

[Def]

Okay, so I replaced the condenser on the 1-4 side and the bike runs better...although, if you git on it and go, it misses like usual. At slow speeds and gradual slow acceleration the bike runs pretty good even at freeway speeds. I'm convinced I have a bad coil that seems to eat condensers so it's time to install a dyna ignition, coil and wire set. In my research, I've noticed
Dynatek coils are 3 ohm coils and my stock coils measure 4.3 and 4.8 ohms respectively. My question is...Is it a problem using 3 ohm coils on my bike? Or am I missing something? Any qualified feedback would be greatly appreciated before I spring for a new ignition & coils. Also, is Dynatek the way to go?

 

[Guest]

The Dyna Green coils are designed for your bike. I have those and the grey 8MM suppression wires. If you go with their ignition and coils you will definitely tell a difference in the way it runs. Check out Z1 enterprises, they seem to be reasonable on their prices.

 

[Guest]

Yes you'll need a Dyna DS3-2 ignition and a DC1-1 Dyna green coils. You can use 7mm or 8mm wire, copper core is all you need but there's no harm if you use suppression wires. You should notice an improvement. Testing the secondary on any coil is simple, put one of the tester leads to one of the coil power connectors and the other lead down the hole where the plug wire goes. It should be around 12-13000 ohms I believe.