Should I set it on fire?

[groundshock]

This damn thing.

Just got done going through the carbs, replaced carb and intake o-rings.

Does the same thing it did before. Starts hard, hardly runs at all on anything but half-choke, as soon as you try to give it gas, death. Doesnt do anything but choke out when you try to crack the throttle.

Idles for crap and makes a funny knocking sound, like its about to clunk out.

It *almost* seems like the ignition timing is off, but i dunno.

Pops through the carbs every so often, puffs some white smoke out the right side pipe.

Obviously will not move on its own power.

I realize this isnt the best info to go on, but I dont really know how to explain it. It just won't run. Period.

Halp.

[Nessism]

Any mods? exhaust? airbox? jet kit? ignition?

Did you do all the maintanence? valve adjustment? points? plugs? plug wires in good shape? plug caps? Voltage at coils?

[groundshock]

No mods. Stock exhaust, airbox. Martek ignition.

Valves were claimed to have been done right before I bought it.

New plugs, gas, plug wires seem to be ok, will check voltage at coils.

Managed to keep it running at half-choke, rode it (!) around the block, absolutely will not rev past 4.5K. DOA after that, and no power whatsoever anywhere.

[groundshock]

L coil, ignition on, 9.35V
R coil, ignition on, 10.21V

Pathetic.

That said, i think this is a contributing factor, but not the full reason. JMO.

[Nessism]

Assuming you did the carbs properly the problem must be the ignition. Is the spark bright blue or pail white? Check ignition timing?

[tas850g]

i'm in a very similar situation, 1979 GS850. Rebuilt carbs, valve adjustments (shims) and runs for minutes before dieing on me even with full choke. can't get it to idle long enough to perform high rpm adjustment. Atleast before i did valve adjustment but after rebuilding carbs it ran long enough to make carb air screw adjustments. Now nothing. It ran great without stock air cleaner but as soon as i put that on it runs as mentioned above. This is with stock exhaust, not sure about jets. Mine has been coverted over to an electronic ignition. I don't think this has anything to do with it. I think the more i work on it the worse it gets. I must be doing something wrong. I'm thinking about taking carbs off and going through them again, double checking everything but it ran well with no air cleaner. I just don't get it. I need some sleep!

[robertbarr]

At this point I'd check the compression. After that, I'd put a container under each carb, open the drain plug and see what you get. Check for volume & contaminants.

[Zooks]

groundshock - sounds like timing / ignition.

tas (thread hijacker ) - sounds like mixture if air intake makes such a big difference.

[groundshock]

Could someone give me an idea of how to check the timing on this with that goofy ass ignition on it?

Compression test -

1 - 105
2 - 100
3 - 120
4 - 110

[tas850g]

Sorry about the Hijack. I just can relate to what he is presently going through. I am thinking of burning mine too. NOT REALLY! I am starting to see the satisfaction of completing a task that once seemed not attainable.

[Nessism]

You should be able to put a test light into the triger wire firing the coils. Then rotate the engine, while watching the timing marks, and take note of when the plug fires.

[psyguy]

You should be able to put a test light into the triger wire firing the coils. Then rotate the engine, while watching the timing marks, and take note of when the plug fires.

and in addition (in case someone may have been "in" the engine before) the firing has to coincide with the correct position of the cranckshaft/pistons

[groundshock]

You'll have to pardon my ignorance, but i have no idea where the timing marks are on this thing.

Only thing under the ignition cover is a big black donut and a nut that rotates.

Just for sh*ts and giggles, in the morning I'm gonna throw the coil relay on this pig. I thought the wiring on my 80 750 was pathetic, this thing is no less than a crime. Wiring is half the diameter of the 80. TINY stuff man.

[psyguy]

it sound like you need a service manual
there may be one on the basscliff's website

[groundshock]

I have it. The procedure does not say a word about aftermarket ignitions.