Help! Starts but wont stay running!

JoeG · July 29, 2009, 04:47:04 PM

So last weekend I switched to the K&N Lunchbox and rejetted to 20/65/142.5...reconnected everything today and fired it up...
With the choke on, bike still needs partial throttle to avoid stalling out, runs "fine" at partial to moderate throttle with no load, but if I let go of the throttle, revs fall to about 1000 and then bike sputters and dies. I've played with the idle adjustment, but it doesn't seem to make any difference at all. What do I need to do to get running??

Thanks!
Joe

joshr08 · July 29, 2009, 04:53:11 PM

stock exhaust? what do your plugs look like?

JoeG · July 29, 2009, 04:59:38 PM

stock exhaust...just checked the plugs, they're pretty sooty...
thanks!

scottpA_GS · July 29, 2009, 05:01:04 PM

Did you take the carbs all the way appart and clean them out well? In another post you mention your slides.. Did you put the clip in the right place? Did you add any washers to it?

joshr08 · July 29, 2009, 05:03:04 PM

your running to rich you jetting for make air flow with the fuel to match but your exhaust is holding you back.

JoeG · July 29, 2009, 05:05:12 PM

I did clean the carbs when they were apart, what clip are you referring to for the slides? I did not add any washers at this point. If I'm running rich wouldn't the washers only make it worse? Or do I completely have that wrong?

josh- if a less restrictive exhaust would help, would drilling the stock exhaust help at all?

joshr08 · July 29, 2009, 05:08:40 PM

washers would make it worse because you would flow even more fuel from the start. no i dont think just drill the exhaust would help enough but i guess i could be wrong on that part.

JoeG · July 29, 2009, 05:40:16 PM

So do I have an option besides doing exhaust immediately, or going back to stock?

Is the question whether it can be leaned out without changing jets back? If that IS the question, what's the answer?

bassmechanicsz · July 29, 2009, 07:07:15 PM

if you want to take the carbs out again and try changing the jetting with jets you already have i might try replacing the 65 mid with the stock 60 and put some washers under the needles to see how that would help with how rich you are running.

Dr.Sparkie · July 29, 2009, 07:09:24 PM

withouttoo muchexperiancein the matter, I would definitly reccommend stock pilots. from what i hear the pilots wont need to be changed. certainly your pilots are troo rich if the bike wont idle. do the newer carbs have the pilot circuit adjust screw?you may want to tighten that upto lean it out some, dunno if itll help.. i'veno experiance with the newer carbs.

bill14224 · July 29, 2009, 09:04:47 PM

Josh is right. You're supposed to change your filters and pipes, then up the jets. You did it backwards so now you're running too rich. Put the stock jets back in or buy pipes. Someone will chime in soon telling you how and where to drill your stock exhaust. That's the cheap option.

bassmechanicsz · July 30, 2009, 05:30:24 AM

He does have what is recommended on the wiki for having just a Lunchbox and stock pipe. But your problem sounds like it is similar to what was happening with me when i was running to rich in the mids when i did my rejet. When you get the pipe you will need to get a new main but i would start with trying putting the stock 60 mid back in with some washers and see how the bike reacts.

JoeG · July 30, 2009, 06:18:08 AM

OK cool, I'll give that a shot after work today...so just the mid, and leave the pilot as-is?

bassmechanicsz · July 30, 2009, 10:56:35 AM

maybe try putting the pilot back to stock too. I dunno though it might take a few tries of different combinations to get it running right.

JoeG · July 30, 2009, 11:01:07 AM

ok cool- I guess i will try putting pilot and mid back to stock tonight, I'll let you guys know how it goes, thanks again!

The Buddha · July 30, 2009, 11:15:40 AM

20 pilots should not be too much ... K&N and stock pipe ... dont even matter, we do 20 on stock bikes with stock filter and pipe ... you have something connected up wrong.
Cool.
Buddha.

JoeG · July 30, 2009, 04:47:39 PM

IT'S ALIIIIIVE!

Changed the pilot and mid jets back to stock, one washer, and fiddled with the idle, and it's running like a champ!
Love the induction sound from the lunchbox around town, it remains to be seen how it will be on the highway.... do you guys have a problem with it?

Thanks again to everyone

The Buddha · July 30, 2009, 04:52:39 PM

Maybe your floats or your mix screws are a bit rich then. The normal 04 bike is lean till you get to 20's and 3 turns.
Cool.
Buddha.

JoeG · July 30, 2009, 04:54:03 PM

So what's the best way to tell if I'm a little lean now?

The Buddha · July 30, 2009, 05:06:09 PM

you're not lean, but a plug pull will tell that.
You're rich, U tube the float level. If its above the gasket, it should really be set right to that and you should adjust your idle scrcew to 3 and go back on the 20's.
The float being high will cost you in gas mileage and soft response when you open the throttle especially between 1/8 and 1/4 ...
As you open the throttle - be it fast or slow if your acceleration is a bit soft, that is side effect #1 for high float. Plug pull after idling for ~5 mins will tell you if its rich or lean. My bet - you're still rich, albeit a lot less so than before.
Cool.
Buddha.

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Help! Starts but wont stay running!