5 turns out

so. im just trying to see if im going about this right.

i recently purchased a colortune tool.

i used it the other night and came up with odd results. the bike was running okay other than trouble "getting out of the hole" and sometimes a shaky idle.

each pilot screw needed to come out about 5 turns in order to see any orange.

i searched for leaks today with a propane torch and came up pretty empty handed. i thought at one point maybe it was evening the idle out, but it was just to little of a difference to be definitive about it.



i was assuming that my pilots being all the way open i have a very large air leak that would respond very well to propane.

am i in the wrong waiting for an extreme change in idle while testing?


i have no high idle. it does take a good 3 seconds for the idle to settle from 5k to 1k. it probably drops from 5k - 1.5 in 1 second then the next two seconds it takes to drop down to 1k.

ive synced it multiple times. always using the yic stick.

have a stock air filter, and stock exhaust. stock jets and business also.

confirmed fuel levels also. all about exactly 2mm.

anything helps?



only get tan plugs when im 5 out. otherwise i look lean.

 

As I understand it you should be trying to get a blue spark not orange with the color tune ? maybe I am not understanding what your trying to do.

 

The Mixture Screws regulate AIR.
Because they are married to the Pilot Fuel Jet, the Air Bleed siphons Fuel from the Pilot Fuel Jet supply.

At 5-turns Out, ... they're Wide Open.

If the Mixture is Lean at 5-turns Out, ... Install Larger Pilot Fuel Jets.

 

Are your valves in spec?

You shouldn't need to re-jet a stock bike, something else is afoot.

 

I agree with what Rick said, go up a size on the pilots. The stock jetting is on the lean side, especially if you are at, or near sea-level.

When doing the color-tune, the orange color is showing that it's too rich, and you don't want to "set" the mixture screws that many turns out. Make sure they are at least a half turn in from where it turns orange or you will load up the cylinders at idle.

Ideally, the setting is half way between the orange color, and when you get the bright white lean color (listening for the cylinder die off while turning the screw in).

As you've probably noticed, you'll need to dial in the mixture screw on each cylinder based on it's particular fuel-air requirements, so a variation of up to a full turn across the board is not uncommon.

Also, be certain that the throttle is adjusted to have the proper play, and you cable isn't binding. It should snap the carbs back to the idle position when released.

Tony

 

i did a valve adjustment just coming up on about 3k mikes ago. i have the stock size 40 jets in there.

when color tuning i am bring to orange and bringing it back just enough to to where there is no more orange visible. that happens to be about 5 turns.

what i found most troubling was that they all were about the same turns even with the the yick stick in.

 

That's actually a good sign that they are nearly even.

Go to the next size up on the pilots. Dial those in with the color-tune, and they should help.

Tony

 

I thought we only used the YICS tool to sync the carbs, not for our mixture settings? What did I miss? :/

 

You missed the fact that isolating the carbs for mixture tuning is as important, if not moreso, than isolating them for vacuum synchronization.

With YICS open, you would get a reading consisting of the intake charge from all 4 carbs.

The ColorTune is our visual substitute for an EGA. Yamaha specifies blocking YICS for the EGA tuning procedure.

 

Ah right, Doesn't quite make sense to me the more I think of it though. Obviously you'd want it blocked to sync effectively since you only want the vac reading from one cylinder at a time, but for setting mixture I'd think it'd be more logical to set the mixture to correct with the engine in it's "as-run" state?

I'm not going to argue the point 'cause if Yamaha says that's the way to do it, that's the way it's done. just didn't seem right somehow :?

 

Look at it this way: Let's say you're "ColorTuning" carb #1. Meanwhile #3 is running WAYYY rich. With YICS open, you'd "see" the overly-rich (combined) mixture and be trying to lean out #1 when in fact it wasn't the culprit.

 

I'm glad I said I wasn't going to argue the point... It makes a lot more sense now!

 

this is the plan i think.

warm the bike up.

stick in colortune plug.

sniff with propane and see if colortune shows me a leak?

do you think it'll come up orange intermittently?




do the slides have a lot to do with idle? they passed the clunk test with ease but had some smaller dark stains on them.

the bike seemed to be operating fine (other than being lean at 3 turns) after my last carb overhaul/inspection(week ago). (i was looking into this bogging down issue again) i didnt find a problem, but after cleaning and reassembling and putting back on the bike, the bike seemed to run smooth again. until two days later, i revved the engine at one of my friends as a joke, and then from there on it couldn't get out of the hole without bogging down a bit at first.

does this cause any red flags for anyone?

thanks for all the help guys.

 

I don't have a color tune plug or a yics tool, now I remember why

 

you're probably right. im making this too hard

 

anybody out there have a stock bike with larger pilot jets?

also. anybody have any real noticeable success finding a leak with propane? can you explain what you found and if it was significant.

 

When I was leak hunting with a blowtorch the revs shot up when I found a leak. I found I had to use quite a bit of the gas to have an effect though perhaps because of the breeze outside, had to have the blowtorch I used turned right up full & it had to be pretty close by the leak to make the revs rise.

But if you find a leak with gas I'd say you'll know, based on my experience of it. Just a thought, are the O-rings on your pilot screws new? they're usually shrivelled & leaky after 30 years

 

i think xj's not made for usa had 41 pilots

 

lean out the pilot screw settings so the engine runs a little rough. this will help you notice when the propane hits a leak.

CN

 

canadian xjs have a 43. but a different size pilot air jet as well.

i had it at 3 turns when testing. instead of the 5.

i popped out the o rings on last disassemble and lubed them up and played with them and they seemed fine. also stuck the torch on the pilot screw holes and didn't get a response. so i believe those rings to be fine. also shoved the nozzle between the carbs at the throttle seals and was left with nothing also. thanks

thanks everybody

 

If the o-rings on the pilot screws are 30 years old, they're NOT "fine."

Just like rock-hard vacuum port caps, they may "look fine" but are they doing their job?

If they're 30 years old, the answer is NO.

 

thanks

alright. might as well do it for 6 bucks.. they did stretch and bend without cracks, but for six bucks. who cares.

going to try propane and carb cleaner tomorrow.

 

well. went through and replaced all the seals with brand spanking new business. bench synced and then threw it on the bike and vac synced with the yic stick in. and now its acting like i actually have a vacuum leak.

i tested with carb cleaner and propane and still cant find a leak.

revs high when i throttle it and if i ride it i can turn the idle down after and it acts a bit better, but after i shut it off and start it back up it doesnt want to idle untill i turn the idle back up and it then it revs high when i blip the throttle.

i did toss the colortune in on one side and it was orange on 4 turns instead of the 5.5 so. looks like something has changed.

im around 3.5 on all the pilot screws.



i'll keep you all informed.

 

Are the copper washers on both sides of the YICS port new? they go hard after a while & need annealing or replacing, I'd prefer new for what they cost.

 

It sounds like you're just slightly out of sync.

Now that you're close with the ColorTune, go back and re-visit your vac sync.

It's an evolutionary process.

 

thanks guys. i colortuned all four cylinders and synced. one little issue that dont know any information about.

i'll check my plugs tomorrow.

when i blip the throttle from idle, when it returns to idle it stutters a bit then smoothes out.

 

ive replaced all the seals but the Hitachi starter plunger valve seat DUST CAP. can i get a vac leak from those?

 

Yep. Are they worn/torn and not fitting tightly to the plungers?

 

i only popped one off because the center off it looked a bit worn. it took some pressure to get it off, so it wasnt loose or anything. i'll have to spray directly on them tomorrow with the propane and see if its the culpret.

thanks a bunch fitz. you provide so much knowledge.

 

cant find any leaks. still running lean. also hearing a weird intermittent buzzing noise while riding. cannot find where the noise is coming from. and cannot control when it happens. only happens when im moving. thought it was the tac or spedo.

took off oiled tac and speedo and reassembled. noise still around. will remove carbs and look for lose things?

also. tac is very very very slow and non reactive in the cold. lubed it up and i have not experienced any change.


was idleing today and i was testing for leaks again. i decided to remove a new vac. plug/cap and when i removed it. it didnt affect the idle at all. is that normal? i tested the open port with a shot of carb cleaner and got a reaction.

now if only i could find the actual vac leak.


thanks for reading.

this is my update.

 

No or inaccurate Tach in "Low" temps.

Normal.

The cold causes the bearing bushing to constrict.
Needle can't move right.
Mine won't work right 'til a Robin craps on the seat.

 

Yep, what Rick said. The tachs really dislike the cold.

You should have noticed some difference when removing a vacuum port cap yes, sounds like they're leaking even if they are new :? really messed my idle up when I forgot to reconnect the petrooster line once.

 

thanks guys.

i was reading earlier on the forum about someone whose carbs (number 4 carb pilot screw was visibly sticking down further than the other carbs) i have this same deal. this makes me think that 3 turns out to start will be way less compared to 3 turns out on the other carbs.

any ideas?

 

Not really, if you think about it the threads are the same on all the carbs so 3 turns out from lightly seated is 3 turns out, regardless of how long the heads of the screws are.

Might be worth checking that the needle section of all the screws are all the same length though in case someone's put a random one in there. (I'm thinking possibly they get shortened though when people chew the head up, then grind it down & put a new slot in)

 

im not so sure what you mean about how long the "heads" are.

the tip of the needle is extruding through the pilot hole into the exhaust port side of the carbs further than the others when seated. i can actually see the tip of the needle coming out. thanks

 

Oh right I misunderstood, I thought you were referring to the heads being different depths in the holes! Have you compared the pilot screws to see that they're all identical? :?

 

i know. puzzling. i had them out and they are all the same. i was reading just one other post that had the same exact issue on the same #4 carb. im thinking 5 turns out on that sucker shouldn't sound so alarming to me.

thanks for the quick replies.

 

been searching for like an hour now and cannot find that old thread. i know someone had the same pilot sticking out the bottom of #4 carb issue. if any one remembers shoot me a message or comment please.

 

You got me interested now, I'll have a look lol... I wonder if it's just coincidence that its the same carb number & someone's just screwed the #4 pilot home too hard :?

Just wondering before why it was quiet on here lately, it's Thanksgiving over there ain't it! Happy thanksgiving

 

haha yeah. happy thanksgiving. im the first to drill out the brass caps. so the screws were not adjusted until i took them out. and ive been very careful.

i dont think i over tightened them. i wonder if the threads allow you to even tighten it down that far. im sure the brass mixture screw would be damaged before the carb body would.


thanks again.

 

Ahh, the plot thickens Probably not that then, if you're the first to go in there.

I think excessive tightening would probably show as a ring scored into the part of the needle tip that seats in the hole anyway rather than damaging the pilot hole in the carb, now I think of it.

I couldn't find any other reference to the thread you mentioned either... :?

 

I WILL FIND IT. thanks for looking.

 

Hmm, only thing that's anything like so far was a post where chacal mentioned that XJ1100 pilot screws were the same except for the tips are a lot thinner, but again as the metal anti-tamper was removed by yourself I don't think the screws could have been switched...

Be interesting to see what anyone else reckons on the issue (the tip of pilot screw number 4 projecting noticeably further than the others through the hole in the carb throat when seated, just to save anyone scrolling back up )

 

there is another place to look for a vacuum leak, where the head joins the block, there's a oring in there on each yics port.
on the other page you said you pulled a vacuum cap and it made no difference, was that the cylinder with the mixture screw problem? it didn't change because that cylinder wasn't firing.
does your sync change when the yics tool is out?

 

yes polock. i think at 3 turns it to lean to fire. i'll have to pull the yic stick out and check for differences in the sync tomorrow.

your assumption may have some merit. i thought i cleaned my yics port pretty well, but there is some residual oil in the port. i just assumed it was residual from when i lubed up the yic stick the last time. could be.

i thought maybe the o-rings were baked from a lean engine, and beginning to fail.

i plan a disassembly tomorrow. i'll let everyone know about how much the sync changes from yic block vs. not.


thanks again everyone.


ps. i do have a seeping head gasket around number 1 and 2 exhuast. not enough to drip ever, and my compression is 145 across all cylinders. i had crossed it off the list awhile ago because of the good numbers. but could i get a vac leak from this?

i'll also take a picture of that tip hanging lower.

 

the yics orings are independent of the head gasket.
a leak in either would not affect the other.
when the butterfly closes completely it would hit the tip of the mixture screw if it protruded, that would drive you nuts trying to get a sync.
i'd take a close look at the low speed circuit in that carb

 

i cleaned up everything so much. i was cleaning clean things.

still no good.

sync doesn't really change with or without yic stick.

with the color tune the screws are at about 4 or 4.5 turns

i attached a photo of the #4 carb when its seated. the rest of the mixture screws are flush when seated. it takes about one whole turn to make number four flush.

went all out with the propane and cleaner again. still no finds. maybe i need to find a smoke machine.

synced without the yic stick. still no good.


well thats the update for you all. wish me luck.

 

Is it my old eyeballs, a shadow, or is there already a mark on the butterfly from running into the tip of the screw?

The bottom line is this: The mixture screw should NOT protrude down into the carb throat.

If you've done "all the right stuff" yet it still does, there is really only possible explanation, and that's that someone before you has messed with that hole. Possibly drilled out a stuck screw and was careless "cleaning out" the threads, I dunno.

But it's a solid sign that there is something not right with THAT carb, and it's screwing up your sync.

If you've got decent color at 4 turns out, leave 'em at 4 turns out. Personally, I don't think it's the mixtures; I think there's something wrong with the #4 carb preventing getting a good sync. I think you're dealing with 2 separate issues.

Remember, #4 is the "in the weather" carb when the bike is sitting on the sidestand.

 

I suppose one way to see if it's the screw or the carb body that's dead, would be to take #3 pilot screw & seat that in #4 carb and see if it still protrudes.

I think your eyes are good Fitz, does look like a mark on the butterfly to me. Someone MUST have been in there before, maybe they just fitted new plugs for some reason (maybe a dealership is at fault?)

 

thanks everyone for continuing to look at my progress and pitch in.


today after work i took my time and synced. then colortuned again. then synced and took the bike for a ride. riding better, but still not the best.

i colortuned them all to the same color. after riding cylinders one and three are no where near as dark as 2 and 4. ?maybe an indication of where air is actually coming in.


as for the picture:

the butterflys open the other way and cannot hit the tip of the pilot screw. the top of the butterfly tilts back into the carb and bottom comes forward.

those lines on the top of the butterfly are from fuel coming from the by-pass hole.

it only sticks out when its all the way closed.