Hey guys, long story short, bike hasn't moved for almost two years and I'm having some trouble getting it running.  I adjusted the valves, changed the engine and tranny oil, and gas and I was able to get it running very poorly.  It would only run with the choke on and the header got hot really fast.  I took the carb off of the bike to see how bad it looked inside and it wasn't pretty.  I cleaned the varnish out of the carb and pulled all the jets to make sure they were clear.  Suprisingly though the jets weren't plugged up too bad.  I also noticed that the rubber o-ring that sits atop the fuel mixture screw was missing.

After reading through all this I'm curious if people smarter than me can tell me if they see anything here that would be my obvious culprit.  If not can someone point out some other things I can check while I have the bike apart.  Any help would be greatly appreciated!

- remove pilot jet and REPLACE IT
- clean the passage above the pilot with monofiliment wire. It is "S" shaped
- new fuel screw oring
- replace the apump diaprhram and seals
- clean out the apump nozzle: spray brake cleaner up the angled passage directly below the nozzle, under the bowl cover

Krannie, on 01 May 2012 - 04:11 PM, said:

Parts on order, will give all of this a go.  Thanks for the info Krannie, I'll keep you updated!

^{Well, took your advice krannie and now I can get it to start better but still not great and it still seems to be running lean; lots of backfiring when I hit the throttle, and still doesn't want to idle on its own.  I'm curious right now if my carb settings may be off.  Any chance maybe I'm running too small of a pilot jet or maybe my fuel adjustment screw still needs to be tweeked?  Right now I'm running a 48 pilot jet and my fuel screw is 2 1/2 turns out.}

Jake76, on 05 May 2012 - 01:34 PM, said:

Did you clean the passage above the pilot jet?

Have you verified your hot start and choke plungers are not corroded or leaking?

Krannie, on 05 May 2012 - 01:47 PM, said:

As a matter of fact I have not.    I did check the passage way above the pilot jet and it was okay.  I'll pull the choke and hot start and check them out.  Thanks for all your help krannie!

Jake76, on 05 May 2012 - 01:34 PM, said:

A 48 pilot is very big.
If it will not idle, the problem lies in the pilot jet / fuel screw circuit, no where else.
Make sure the idle screw is not artificially high.
2.5 to get best idle means your pilot jet is too small, OR that you have an air leak. Well, the pilot is NOT too small....

Are you following the standard pilot jet / fuel screw protocol?

With a hot engine:
Adjust fuel screw for highest idle. Drop idle with idle screw. Repeat until you can keep it running with the lowest idle. 1/8 turns to fine tune, with a throttle blip and a 10 second wait between turns. You want approx 1.5 turns. The fuel screw must have a washer and a new o-ring for it to work.



As mentioned:

- hot start plunger: they corrode, get stuck part way open, and leak
- Air jet in intake bell: they fall out
- carb boots: they get old and crack and leak
- fuel screw washer and oring

Well I checked the plungers on the hot start and chokes and everything looks good there.  Air jet is intact and the carb boot looks good to me but I think I'm just going to replace it anyways.  I don't have a replacement 48 pilot jet so I tried a 45 that I have.  It didn't seem to make a difference.  I think about all I can do is try a new 48 pilot jet and if that doesn't help I think I'm going to have to throw in the towel and get someone to look at it that knows what they're doing.  I don't think I can tear the carb out of this bike one more time and not put a bullet in it.

Finally figured out what the problem was.  After much fiddling around with cleaning the carb and trying different jets and getting nowhere I decided the carb isn't the issue.  So I happen to have an extra stator lying around so I put it in just for kicks.  Good news, that was the problem.  Go figure.

And now you have a clean carb to boot.

Edited by RollingJ, 30 July 2012 - 07:47 PM.

RollingJ, on 30 July 2012 - 07:45 PM, said:

Hell yeah!  Hopefully now I can keep it that way too!

Good call to check the stator, Jake! I had mucho problemos with aftermarket stators on my '05 X but never a problem with an OEM.

cubera, on 06 August 2012 - 03:53 PM, said:

That's what's kinda got me scared.  This is the second oem stator I've had go bad on me.  

Krannie, on 05 May 2012 - 06:14 PM, said:

Is it OK to run the bike out of fuel?  Normally I do this after loading the bikes, so that it is cooled off while driving home, it usually takes 2 minutes or so to run out.

David B, on 08 September 2012 - 02:57 PM, said:

Yes, but there is still fuel in the float bowl. If you want it dry, you'll have to open it up, or lean it over on both sides to drain it dry.

Thanks Krannie, I have a bet with a friend who has a two smoke, I say he should not run his dry? Any comment on that one?

David B, on 09 September 2012 - 02:52 PM, said:

He is absolutely correct. Dry starting is not friendly to cylinders........