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Discussion Starter #1
Finally got my bike fully fixed, did all adjustment things including the carbs.
Fuel level is half millimeter above carburetor body edge.
Pilot screw is set to 2 3/4 turns.
Cleaned with lots of carb cleaner.
There is kinda slow-ish return to idle, this seems like lean condition on idle circuit!? No backfiring, acceleration is good, fan never turned on etc, all seems good, just return to lower RPMs is kinda slow, makes it bit hard to downshift...
I got these new NGK plugs and this is the result after 15 mile ride at about 35mph average speed. I'm wondering about this white residue shown on pic. Is this from lean condition or something else is going on?
Previous sparks are been fouled in a matter of minutes because of rich mixture and oil burning, I sorted this out.
 

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I concur with SamR, it may be a bit lean (which at low speeds isn't detrimental, just annoying). What are your carburetor jet sizes? (including jet needle)
Stock sizes:
Pilot jet: 35
Main jet: 102
Jet needle: N2WE

Are there any leaks on the airbox size of the carbs? Are there any extra holes in the airbox?
 

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Do the carbs have Low and High speed adjustment screws? Seems when I cleaned mine up there was one screw on the bottom of it, that I'm thinking was maybe just the jet needle. But I didn't take the welch plugs out.
 

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Do the carbs have Low and High speed adjustment screws? Seems when I cleaned mine up there was one screw on the bottom of it, that I'm thinking was maybe just the jet needle. But I didn't take the welch plugs out.
The jet needle is connected to the slide in the throat of the carb. It meters fuel from about 1/4-1/2 throttle.
There is only one screw adjustment and it is for idle fuel. It meters from idle to about 1/8 throttle. All other adjustments are metering orifices.
 

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Discussion Starter #6
Stock sizes, didn't mess with that. Sizes are:
#35
#102
N2WD (European bike)
There aren't any leaks on intake side nor holes in airbox. New carb boots and air filter (oiled it with air filter oil)
Should I maybe replace jets? Bike is from 1999 and I'm sure jets has never been replaced nor went through ultrasonic bath.
Soaked everything in carb cleaner and used guitar string to clean jets.
 

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Fresh jets couldn’t hurt but worn jets in your carbs don’t cause lean conditions.

Adjust the idle mix for best idle instead of adjusting to a spec. If I remember correctly there is about one turn difference between the idle mix screws on Hidalgo. ...and Hidalgo’s carbs are perfectly balanced.
 

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How do you suggest one adjusts those screws on the machine? Seems they are underneath the carb in a tight space. Just use a stubby or maybe one with a bend in it?
 

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Discussion Starter #9
Thanks for replies everyone, I'll play with those screws and see if it solves the issue, if not I'll send the carbs to ultrasonic bath.

Sam, type keychain screwdriver on ebay. I got these, great for pilot screws and costs few bucks.
 

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Ah, good! When I put them back together I neglected to really tune those screws, I think I put them both at 2 1/2. Bet I could get it to idle a bit better.
 

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Discussion Starter #12
One spark plug failed. These NGK plugs are terrible...Went back with Denso, much more reliable. Set pilots to 3 turns out and that will be my starting point for further adjustments
 

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