Can someone identify this symptom.

[The Buddha]

I suffered with this a month or so and finally fixed it today. I didn't even have a theory till 5 mins before I fixed it, stumped.

OK so the bike starts great on choke. Runs fine for ~5 seconds before it starts missing. Take off the choke, and it continues for the entire duration of the ride. Hot, cold, raining dry, fast ride, slow ... whatever, makes no diff, it sneezes every 5 seconds. Worse yet it wont run right either, ~1/4 throttle it always misses ... a sneezy miss. I behaves fine at steady throttle as well as when accelerating ... it sneezes @ that 1/4 throttle mark regardless of rpm or speed.

Worse yet, air screw had no effect. Closed to 4 out is all the same.
Float level had no effect. 2 mm under to 2 mm above the gasket = same damn thing.

This is the second bike with that issue I have fixed, ironically the first one also was in the first week of july and I fixed that in no time. This took me a month+.

Anyway anyone wanna try their hand @ figuring it out.

Cool.
Buddha.

[burning1]

I had strange problems with the carb breather tube. Any chance that, or one of the crankcase vents was the issue?

[pandy]

Sounds as though she has a cold. 

[burning1]

Pandy, you ride at Thunderhill? I'll be racing my GS there next weekend.

[werase643]

one of the lil ribber vac plugs came off the top of the carb?

[the mole]

Its a gremlin.

[mister]

Starter button.

Michael

[jeremy_nash]

the bar that links the choke operation across the carbs is a little bent, holding one carb in partial choke at all times

[Paulcet]

Loose throttle plate?

[mister]

Lack of Magic. You put the magic back in and she ran sweet 

Michael

[The Buddha]

Man ... all wrong .. all of em ... not even close ... maybe my escription is a little bad then ...

So here is the next clue ...

Its acting rich ... with the air screw closed its still rich @ idle. I raised the float ... it was 2-3 mm under the gasket ... and still rich from 0-1/4 throttle, very obvious @ idle ... coughts every 5 seconds and dies if you dont rev it. Its stock jetting with a pipe and stock air filter ... still rich as stink ... puffing black soot and smoke every time I blip the throttle ...

OK so now who's got the answer ...

Cool.
Buddha.

[mister]

Plugs. Leads. Ignition advance/timing.

You were using glow plugs instead of spark plugs?

Aliens abducted the magic?

Michael

[Homer]

Was this a "new" bike, or one you've had and it just started happening?
Cause I'm thinking a homebrew timing advance in the wrong direction. 

[The Buddha]

Mister - nope its definetly fuel, none of what you suggested.

Homer - I have had this one running alright through winter. It started doing this ~mid may. I didn't ride it a lot till the 7th cos I had that maxim I was riding and working on selling it. On 5th june I sold it, and on 7th, the very next time I rode a bike I got rear ended, so its been doing it longer than it has been bothering me. Of course since the accident on the 7th of june, it sat @ work for most of that week, I got it home and rode it 2-3 days the next week, and 2-3 days a week after that.

Lets just say it started suddenly, oddly enough with the weather getting hotter, but I can promise you its unrelated to that.
It also isn't smelling like gas at all. Its been one tough nut to crack, especially cos it was so un intrusive, the first time this happened I got it in a few minutes and fixed it in under an hour. But it also puffed white smoke, reeked of gas and overall was very unmistakeable.

OK so guess away ... I'd put the answer up tommorow night.

Cool.
Buddha.

[Homer]

This is infuriating. 
What about the o-rings for the little slides for the choke? 

[JAY W]

Over filled with oil?
Combo Jay.

[the mole]

Choke valve not closing properly.

[noob]

Little plastic thing that holds one of the needles in the slide had popped off?

[mister]

Choke valve not closing properly.

What he said ^^^^

Michael

[black and silver twin]

Ill bet you cursed at her when she wasnt running perfect and now shes mad with hurt feelings.
just appologize and she'll ride good again. gigity.