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Idle speed when choked?

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Looked through the manual and I can't find any references to a separate idle adjustment on my FCR for choke in vs choke out.

What's happening is when I've got the bike tuned in for a nice idle under normal conditions, when I activate the choke it is screaming.... seems like it's pushing WAY too high RPM, and it will idle with the choke on significantly lower.

Problem is, if I idle it down, then when I disable the choke, it dies and I have to run the idle up again.

Is there a screw to adjust the "choked" idle speed?

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If the engine is idling high enough to remain running at anything above a low thump (1500 or so?) when warm, it's screaming any time the choke is engaged, warm or cold. Temps are in the high 50s to low 70s, elevation -200 to 1000ft.

Buddy's bike isn't as bad, and both are modded identically... JD kit blue #4, 45 pilot, ZipTy (he's a 1.5, I'm now at 2, but same problem at 1.25), ACV disabled, I'm running 182 MJ, he's running 185, 40 LJ. YZ pipes and cams, airbox opened.

Mine has always done it, even when bone stock.

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sounds like your bike is lean on the pilot circuit or has a air leak.all the choke does is add more fuel.

when they are lean like that you have to have the slide raised to far for idle.when you add the fuel they take off.

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sounds like your bike is lean on the pilot circuit or has a air leak.all the choke does is add more fuel.

That's what I thought... just a plunger with no connection to the throttle, but it didn't make sense.

when they are lean like that you have to have the slide raised to far for idle.when you add the fuel they take off.

Hmm.... interesting. May be an air leak, though I've checked the boot. I did have a hanging idle when I had the fuel screw at 1.25 turns. It might need to be cleaned out from that load of bad fuel that hosed my buddy's bike a few trips ago. I'll have to pull the carb and run some cleaner through the jets.

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What number is your starter (choke) jet. I'm not sure what would happen with the starter jet loose in the carb body (a faster or slower idle)?

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Yes, starter jet. What is it and what does your friend have? Certainly not ruling out the other suggestions, but that's directly related to the choke.

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the starter jet controls the amount fuel supplied to the choke.however,it does not control how fast the idle is when the choke is applied.if a warm motor speeds up when the choke is applied there is a issue.its lean for some reason.

if the motor sped up then went instanly rich and dies,thats normal.

same deal with the hot start.if you apply the hotstart at idle the idle should at least get crappy if not die.if the idle speed picks up it rich.it likes the extra air.

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We've changed the MJ, needle, pilot, leak, and the air jet (per ACV removal instructions in Thumperfaq). Have not changed the third jet in the bowl.

I'm pretty sure it's a partially blocked pilot circuit, considering that my buddy's bike is set up and jetted nearly identically, and though it's always been a minor issue, it's become worse recently. After the bad fuel, we completely tore his carb down and cleaned it. Mine seemed okay so we just dumped the bad fuel.

Stock, the hot start didn't seem to do anything. After we moved to the 45 pilots, the hanging idle went away, and the engine would slightly speed up when using the hot start. This trip, I didn't need to use my hot start at all.

Ya... it all points to a lean pilot circuit.

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the starter jet controls the amount fuel supplied to the choke.however,it does not control how fast the idle is when the choke is applied.

Should the starter jet need to be changed when going to a big bore........i.e. athena 290? If so, richer?

same deal with the hot start.if you apply the hotstart at idle the idle should at least get crappy if not die.if the idle speed picks up it rich.it likes the extra air.

So...........is that true at even partial application, or just if you pull it fully? Mine will idle up w/partial application, but dies with full. I'm still trying to get my 290's pilot/starting circuits right. Bike seems to run good, but starting is a royal pita at times although first kick others.

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Should the starter jet need to be changed when going to a big bore........i.e. athena 290? If so, richer?

So...........is that true at even partial application, or just if you pull it fully? Mine will idle up w/partial application, but dies with full. I'm still trying to get my 290's pilot/starting circuits right. Bike seems to run good, but starting is a royal pita at times although first kick others.

the starter jet should not need to be changed.does the bike start well cold?

if you apply the hot start even partially and the idle raises/improves you have rich pilot circuit.

that is very possible with the big bore.

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the starter jet should not need to be changed.does the bike start well cold?

if you apply the hot start even partially and the idle raises/improves you have rich pilot circuit.

that is very possible with the big bore.

Oops..........looks like I'm in the process of hijacking this thread. :bonk: Sorry WheelsUp. :cry:

Anyhow, I started my own. :applause:

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Oops..........looks like I'm in the process of hijacking this thread. :applause: Sorry WheelsUp. :bonk:

No problem... my question was answered, I just need to get back out to the desert home and work on it.

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