Help - can't get it to Idle

Bike was all dialed in perfectly 2 yrs ago. Ran it around for about 1 yr. Then bike sat idle for the last year.....so with that said.....Recently as in a month ago,I pulled off the carbs and went thru "The church of clean" . Cold start enrichment passages all clear as well......did not replace throttle shaft seals as they were replaced along with fuel o-rings 2 yrs ago when I first was dialing it in.....

Replaced battery yesterday & apply full choke and it started after a few tries on the start button. Seemed to run a little rough as it was cold but it eventually idled steadily but at a very high rpm as it warmed up......( idling high because of full choke)......

My problem is the bike is dying as i take off full choke.......even me turning the idle adjustment screw to open the throttle plates a little more is not helping. The bikes dies.....

I know I have no air or vacuum leaks.......intake manifold boots & airbox carb boots are on nice & tight with no holes or cracks in them......great shape even after 3 yrs.....

I thought I had fuel in my oil ( detected faint smell of gas in oil but was not 100% that I had oil in my gas but did an complete oil change anyway........checked & readjusted fuel levels in carb bowls if needed.....

I know eventually I will vacumm sync this with Morgan Carbtune Pro & colortune the plugs......

The problem is that I need a steady idle without the enrichment circuit being on.......

Any suggestions ???

I really don't want to take these off a 3rd time......but if I have to ...I will break them down completely once again and replace throttle, fuel o-rings, enrichment washers & o-rings which were replaced 2 yrs ago as well....

These carbs are clean to the best of my knowledge......

Just can't get it to idle after taking it off of choke........

WTF....

 

Where are your mixture screws set at? Those control idle mixture, too lean and it won't idle off choke. Fuel levels good in the bowls? After that, I would check mechanical linkage, make sure the idle speed knob is actually opening the butterflies.

 

Shouldn't have to do that after two years unless you stored it with berrymans carb dip in the carbs or something.

 

Jay, Thanks for the reply.

Nope did not do that with berryman's......idle mixture are temporarily set at 1 1/2 - 2 turns out from bottom......carbs were bench sync's with idle throttle screw set to see that silver of light thru carbs.....after bench sync looking up into to carb throat( from engine side ).....I can see the little fuel hole on each carb at the top of the butterfly........they are all at about the same location...that is a good sign for benching

I have morgan Carbtune II & colortune but have not perform ......why you may ask ??? because I need a steady idle at 1,050 rpm without the choke on ......

Can't figure it out yet.......I am dumbfounded at the moment.....

Brand new gas in tank....petcock cleaned........fuel levels in bowls checked 7 adjusted if needed......

I will upload a video tomorrow so one can see what is going on........frustrating.......

 

go to 2-1/2 turns out from soft bottom on mixture screws

consider the pilot jet passages may be clogged.
what do your spark plugs look like?

are all 4 exhaust pipes getting hot?

 

I have the same problen untill i take the carbs the last time off and make like this

http://xj650.blogspot.si/2009/04/how-to-bench-synch-your-carbs.html?m=1

Then i realy realy well clean that port read all and watch video

http://xj650.blogspot.si/2009/01/how-to-clean-enrichment-circuit-well.html?m=1

Then i pun all four mix screws on 2.3 turns-guys here they told me that this is the start position of screws ,and now my screws are on #1- on 3 #2- on 3.15 #3- on 2.55 and #4- on 3.05 i writte the last numbers 0.xx like a clock- like this was easier for me to remember the positions.
But this sync was made with my ears soo if you make real sync with tools will be maybe better ,but my bike wit that sync work super.

 

Sounds you're running just on the enricher circuits---- sounds like some, or all, of your idle jets are clogged.

Dave

 

Do a running synch of your carbs. When you had the carbs off did you clean the jets? after setting a short while ethonal turns to gum unless there is a fuel stabilizer mixed in . Usually turns green on the inside of bowl , this can plug up passages that spray cleaner will not get to, soaking is only real way to clean out.

 

Have you checked with unlit torch etc? I had a similar issue when I first fired my bike and turns out all the new intake boots were delaminating internally and had major leaks.

 

Jay....new boots were delamination ????

Hope you get new ones from whoever you got them from...

 

Yup, see below. Installed for two days. Got em from Chacal who took them back without question and got me a set of the Yamaha ones. It pays to buy parts from the proper people.

 

XJ4Ever = A+ Customer Service

 

Did you try running some Seafoam through the carbs yet?

 

That tells your right there, that you're running on only the enricher circuit. Your idle circuit is not drawing fuel.

 

Just got done spending the good part of the day tearing down the carbs once again ( did not break rack as throttle seals & o-rings were just replace 2 yrs ago.....

Well apparently I went to Sunday School rather than to Church the last time I had these carbs apart.

Kick myself in the ass for not seeing this the last time these were off.....I have had this bike 35+ yrs now......you would think that I should know better

.......anyway it appears that the pilot jets were clogged ( 2 of the 4 )....& #4 pilot jet is kind of buggered up however the hole in the jet is OK......it is open & clear...just cant get it off to replace ...so I left it alone but clean it out with my enrichment drill bit ( that drill bit has come in handy for the pilot jets as well the enrichment circuit ) ........so enrichment circuits are clear, pilot jets are clear, main jets are clear, all air jets are open, brass choke plunger are sprayed out, the idle mixture screws were taken out & passages were clean, put back together and turned 2 1/2 turns out from soft bottom. Floats & fuels levels were checked & adjusted if needed. Carbs have been bench sync'd.

Will try to start here shortly.......to be continued......we shall see....

K-moe, Hogfiddles, jayrodoh, Stumplifter, jetfixer, XJ550H, Andy555......thanks for the suggestions or replies.......

Hog , you probably hit the head on the nail here......I will know shortly.....maybe I will upload a video of where I am.....

Thanks....

5ofakind

 

Hey five,
I was just in sd fishing for the last week. Got back today. Anyways, looks like your well on your way to fixing your problem. If you would've posted on Sunday I could've came by a helped out a bit. O well. Good luck with fix'n her up.

Once you get the bike running go snap a few new pics!

 

Question in the carb throat ( Manifold side ) there are 4 holes at top of throat.......

one is where the the idle mixture screw ( pilot screw - per the service manual ) penetrates the carb throat
one is the choke ( Cold Start Enrichment Circuit )

What are the other 2 little holes - manual indicates a by-pass hole......huh ??? what are these 2 little holes - what is the first one & the other that sets right behind it .....

I forget ??? Please advise........I know bench sync'ing.......the first little hole shows and I have a silver of light at the bottom of the butterflies.....

 

Just Started it....Kicked over just fine on full choke...then went to half choke ....still everything Ok,,,,,then no choke and I was able to idle at 1,050 RPM a few minutes, starting bumping the throttle a few times , RPM went up & came back down to 1.050 RPM....but not as fast as I like........but now there seems to be a hanging idle between 2,00 to 3,000 RPM.....

Idle mixture screws are all 2 1/2 turns out from bottom....... I still have not vacuum sync nor colortune yet ????

Hanging idle suggests vacuum leak ...doesn't ???? I am pretty sure boots - manifold & airbox are all right & tight & vacuum caps are all good & tight as well....

Any suggestions ???

 

1st- if you haven't synced, then that's probably why you're getting the angling idle. It will probably go away once you do that.

2. The other holes---they are the passages that allow a smooth transition from idle to main jets. As you open the throttle the butterflies pivot out of the way, and allow a bit more fuel through the holes, eventually the mains start taking over

3. The idle mixture is just that--an adjustment for the mixture at idle. Once you're on the mains, the idle mix screws doesn't really contribute a whole heck of a lot. By that time, the fuel is coming through the mains, and the air is coming straight in from the airbox and filter..... To put it simply

 

So do I colortune first then vacuum sync with Carbtune or vice versa...... ???

 

Colortune first. Synch won't help if the mixture is wrong.

 

Here is video before colortuning & vacuum sync'ing.....

All comments welcomed....

 

Colortune,pls.hehehe

 

sync color tune sync colortune its a rinse lather repete kinda thing until sync is showing no need to readjust then a final color tune

 

I sync first then colortune.

Other than still needing a syncing, it sounds pretty good, and I like the throttle responsiveness

 

Either way should be fine- the "rinse, lather, repeat" is what I found helped me get my XJ650 Maxim dialed in proper.

 

Was doing vacuum sync with Morgan Carbtune II & notice no vacuum response out of #4 carb when turning sync screw.......well the pic reveals what is going on.......frickin is half on & half off......see pic.....

I have #1 #4 manifold boots off to do my fuel level setting. I mount them to a board & then mount carbs to it.......rather than doing the PVC tool setup for.. Well anyway, somehow it got off when reassembling.

I am surprised how good the bike sounds on 3 of 4 cylinders.....with that vac loss on #4........interesting.....

Well need to correct it by loosening the allen head boots to #4 boot or yanking carbs off once again then #4 boot & re-seating gasket.........

Oh well, after this should be a breeze colortuning & sync'ing......

 

after sync......almost there