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Discussion Starter #1
What if you adjust the idle mixture screw all the way until it's gently touching the seat, but the engine doesn't really stumble?
I made sure my bike was good and warmed up (rode about 45 min) before I made any adjustments. Couldn't seem to get it to stumble on the lean side (not like when I used to play with the Holley on my old truck). Went back to approx. 2 1/2 turns out for now. Checked the mileage, seems to be around 39mpg, and seems to run good & strong.
I changed from a 45 to a 48 slow jet a while back (after installing a K&N air filter & slip on mufflers), but did no other mods to the carb (except the idle mixture plug).
Is this a problem or am I paranoid? I want to make sure it's right, so I don't have to keep messing with it.
Thanks in advance for your advice
 

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Sometimes motors can be like people, no two alike and in your case it seems strange you cant get it to stumble. Check your plugs & see how they look. If they look good -done if not go from there.
 

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Thats sounds pretty normal. The adjustment range of the mixture is such that it won't enrichen it enough to affect idle speed in real-time on some bikes. BUT, if you were to leave the screw turned all the way out and let the bike idle for 5 minutes or so you would probably find yourself with fouled plugs. Stick with the recommended method of winding it down on the lean side until it stumbles and you'll be fine.
 

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Discussion Starter #4
Update...

I tinkered with it a little bit, and did finally get it to stumble (I'm not sure why it wouldn't do it originally).
This past weeked I pulled the carb and shimmed the jet needle about .033". I re-adjusted the mixture and had no problems getting it to stumble. So now I am very satisfied.
I also took the time to make sure my throttle cables are adjusted properly. I have absolutely no complaints about how my bike is running right now :D !
 

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spits awful

My 2002 Road King FLHR has been fitted with sampson Silver Bullet mufflers, High flow kit, Screaming Eagle kit and rejetted...I am getting about 35 mpg (buddy of mine with stock pipes burns 1 gallon less per tank and has no soot in his pipes). My complaint is the spitting/missing when stariting out from a stop, etc., or accelerating in a turn. Durring my 1000 mile service, a different dealer took a look at the carb and told me they turned up the idle, was too low, and said they felt the 45 jet was too big...but they didn't have another size(smaller) jet to replace it with. Any suggestions, when I take it in for the 2500 next week to the dealer who installed the stage 1. I know it's running too rich, well in my opinion, I'm no mechanic, but I doubt almost everything my service manager tells me...Again, any suggestions? JB:confused:
 

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Hmm, the condition you describes sounds as though the slow jet is to small. Hesitation, spitting and unsmooth at low RPMs are usually a lean condition. Is the 45 jet stock, smaller or larger than stock? Its possible to have a lean condition at low RPM but run overly rich at high RPM (main jet too big). So yeah, you can have poor mileage and sooty pipes but still be running lean at low RPMs if the slow jet is too small.

You read this article over on nightrider?
 

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Is the 45 jet stock, smaller or larger than stock?

I have no idea what the stock jet is...and I have very little confidence with the selling dealer who set this all up. I know while in Myrtle last week the idle seem high at times then low at other times...I am also very careful about fuel I use...try to stay with Amoco 93...It can be frustrating, just wish I had a decent mechanic who was also concerned about paint and chrome. Thanks for the link to the article. Guess, I'll take this back tot he selling dealer and insist they get it right. The delaer who did my 1000 thought the jet was too big...
 

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I'm running the stock low jet (45 I think) & a 180 main jet in my '00 Deuce & it runs great ( no flat spots or stumbles). This was done with a dynojet kit so there are other parts that have been changed in the carb also. I usually get 39-40 mpg. & i'm not exactly easy on the throttle either, highway speeds of 75-80 mph. normally! I'll see if I have the part # of the kit if your interested, it was about $70.
 

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Maybe this helps some, had a low speed "cough" with a DWG3 that has SEII's, SE air filter, and a jet kit installed from mile 1. Put a # 50 low speed jet in, still coughed, almost to a stall, really pissed. Went in for my 2500 yesterday and the wrench replaced 2 thin and 1 thick O rings off manifold. Upon inspection found a slight polishing on one rubber ring indicating an air leak. Result, bike runs smoother, better transition, and praise the Lord, no coughing. Dealership is returning them to the Motor Co. If the rain ever stops here in Vermont, I'll put some serious miles on and report back. FWIW getting 39-40 MPH.
Take care...ride safe...
:)
 

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Hard to tune a bike with $hit pipes. If it spits thru the intake on takeoff it's lean at that point, but it could well be the pipes and not the jet.

Every bike is different and now and then you will find one that runs well with horrible pipes and you will also find one now and then that runs poorly with good pipes.

Don't forget the effect of low jet, needle and main is cummulative, and if you are set on running a specific set of pipes for cosmetic reasons you have to give the bike whatever fuel amount it wants. If you are forced to go very large in one area you well might have to take fuel away somewhere else, and in the end some pipes will actually make less power then stock with higher fuel consumption.
 
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