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Discussion Starter #1
The other day I'm riding to Sacramento on some business and when i get off the freeway i immediately notice that I'm running super rich and she's trying to die on me, so i reach down and speed up the idle adjuster and park. I was running late, so i didn't have a chance then to check out what was up.

I come back after it had cooled and fired it up, figuring i'd listen and try and figure out what the issue was. it was still running real rough and as i'm looking down on the clutch side carb, i notice a little spring sitting on top of the engine case. i'm thinking, where the hell did i pick that up? then it dawns on me, that's the spring that goes with my a/f adjustment needle. my heart sinks, then i get down on my knees figuring i'm now stuck in sac w/o a needle. then i see the little rubber grommet, the metal washer, then hiding under my breather hose, the needle itself. it managed to fall out either at freeway speeds or slowing off the freeway, and all the parts stayed with the bike?!? whatever. i say a little prayer to the moto gods.

i was able to fashion a makeshift screwdriver by biting down on the end of a ball point ink pen ink tube and screw the jet in to around the right number of turns.

ok, so here's the issue #1. when i fired her up initially, with the mixture needle out, she gave one of her misfires that i've been worrying about (and that have been getting more frequent). what was interesting was that when the misfire (or whatever it is) occurred, there was a bunch of back pressure and gas was blown out of the empty needle hole. i feel like at least i know which side is giving me issues now. :)

any idea what's going on here? my guess is that it is a valve issue, either sticking or out of adjustment, one not closing when it should be closed. i'm just over 21k miles, and prob due for a valve job, but i wanted to check here so at least i'll have some idea what i'm talking about when i take her in.

issue #2. i'm guessing the needle coming out was the result of having too lean of pilot jets and thus having to back my a/f screws out 4+ turns. Vibration PLUS the back pressure just blew the little sucker right out of there. here's the problem; my pilot jets appear to be seized in the carbs. having just changed my sprockets and chain, i'm kinda wrenched out for awhile and i'm dreading the idea of taking the carbs off the bike to try and get the damn jets out.

However, when i do, any tips on loosening the buggers? Maybe a penetrating oil like WD40?
 

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I was once told it is better to be lucky than good at something I was attempting to do.:D I like your makeshift screw-driver!

1. Try starting the motor with your right hand UNDER the handle bar and just pushing on the starter button with your thumb...this INSURES no throttle during starting. Giving some throttle during starting--especially on a warm engine causes a pretty good pop out the exhaust on mine.:)

2. Were your pilot screws set with an A/F meter? In many cases the pilot jets used are bigger than needed or the pilot screws are set too rich, IMHO. In my experience with my 790, if I set the pilot screws rich enough to do away with any popping on decel overrun, the A/F meter will show I am WAY TOO rich.

3. My guess would be that 4 or more turns out on the pilot screws are very close to the limit for the spring to keep vibration from "backing out" the Pilot screw.

4. If you had your valves checked and shimmed at 12K, I would doubt if you have a valve problem. IMHO, one would have had to tighten up enough to burn one in order for the valve to be the culprit.

5. WD Fortay is NOT a penetrating oil. In fact of all of its manufacturer's claims, about the only thing it does well is clean. It does NOT displace water--it actually attracts water....guess I had better end my rant before the flame throwers that believe in miracles get upset.
 

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If your bike was running well with the idle mixture screws backed out over 4 turns, then I think that you need to go to 42 jets. I agree with Redbird that you probably exceeded the ability of the spring to keeps some pressure on the screw, allowing the screw to simply vibrate out. I don't think that you have a valve problem.
 

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Discussion Starter #5
yeah, i know my a/f screws are further out than ideal. i've got a colortune coming in the mail, so i hope that gets me in the ball park after all this hit and miss. if i'm still out past three, i'll start making the change of pilot jets more of a priority. but, as i mentioned, they're really stuck in there. whoever was in there last got them in too tight.

btw, sorry i mentioned WD40 :) one of the most debated products online! i had a momentary lapse of judgment, and let it be known that i don't even own any. that being said, what would be a decent lubricant or solvent to use to help get the stuck pilot jets out if it comes to that?

regarding valves, i just went through the service records i received when i got the bike a few years ago, and i'm not seeing a 12k valve adjustment having been done. doesn't mean it wasn't, just means that if it were done, i didn't get the documents. i'm leaning toward taking it in for an adjustment just for the piece of mind that its been done, and done correctly. anyone want to buy a kidney so i can swing this?

maybe, rather than trying to diagnose my moto via my lacking description of the problem, it would be wiser to ask what a maladjusted, burnt (?) or sticky valve would sound like at idle?

tx for your responses!
 
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