Hanging Idle after wide open

[GasGas]

I have a hanging or surging idle after wide open conditions. Is that too lean on the main or needle or too rich? Works fine otherwise.

 

[Jiikoo811]

Too small pilot jet or airscrew just too much open.
Try first turn airscrew more in, it should help if help but not enough you need step bigger pilotjet.
Sent from Razr MAXX

 

[Jakobi]

That would be my first test too. Either drop the slide a little or close the air screw a tad. If it still hangs and is strictly after doing WOT runs, I'd be thinking about the main. When you back the throttle off just a bit (from WOT) does it surge or run on, are you getting any pinging? What sized main are you running with which needle? Have you done a plug chop at WOT?

 

[GasTimppa]

chec left side crank seal too...

 

[rosco]

You always want to set your main before any other circuits. Go out and run the bike hard for about 5 to 10 minutes in an area where you can keep it in the wide open position most of the time. A nice open field works great where you can keep it wide open for a couple hundred yards and then back off the throttle to turn and then get right back on the main again. Kill the bike immediately and do a plug check. You should jet for a nice light brown plug color. White too lean, dark brown too rich. Once you get the main set then go straight to the idle circuit. Bike should idle at its best at 1 to 3 turns out on the air screw. If its less than 1 you need a bigger pilot, if its more than 3 you need a smaller pilot. Now comes the fun part trying to get the right size needle to make it run the way you like it. Everybody has there own special needle that seems to work for them. I have had good results with the YZ needles, N3ew,N3cj and N3cw.

 

[clw]

Too small pilot jet or airscrew just too much open.
Try first turn airscrew more in, it should help if help but not enough you need step bigger pilotjet.
Sent from Razr MAXX

Just curious, what needle are you using?

 

[Jiikoo811]

If you mean my bike. It have stock needle clip2 pos. And 45/178 jetting as1 carb 38mm doma pipe and s3 billet head..works ok in mx track,single track and on road... Its road legal bike..

Sent from Razr MAXX

 

[clw]

Thanks, but I was curious about the OP.

The only time I have had hanging isle problems on my street legal GG is when I drank the kool aid about the Suzuki needles. For street use I'm back to a CCK for its smooth behavior. The aggressive needles do my rear tire in too quick for me!

 

[Jakobi]

Thanks, but I was curious about the OP.

The only time I have had hanging isle problems on my street legal GG is when I drank the kool aid about the Suzuki needles. For street use I'm back to a CCK for its smooth behavior. The aggressive needles do my rear tire in too quick for me!

If you went with one of the recommended H/W/J diameter needles on an AS1 model carb, fitted to a pre 2010 gasser its not surprising that you encountered hanging idle issues. The older style carb definitely requires an F/G diameter to run well.

 

[clw]

F or G, huh? I tried both a NEDW and then a NEDH. As I recall the H felt a little thick off idle when paired up with a 42 and the AS in the 1.7 to 2.2 range. It ran fine 80% of the time but exhibited a very different behaviour when you got the engine real hot. That's when the idle got flaky and it would feel real lean. Felt like it had an air leak. But the CCK needle back in and the hanging idle went away.

Maybe the needle jet is trashed (it is 12 years old) and that's contributing to the difficulty in tuning.

 

[Jakobi]

Definitely sounds like you were a bit lean somewhere under heavy loads, and could be the first taper of the suzuki needle contributing to it. May have just needed to be a half a clip richer. Never the less, if the CCK works then nothing at all wrong with using it. I've never had to work with an earlier model bike or carb so don't have any first hand experience to fall back on. Appreciate hearing about others!