bought an xj650 desperately need help getting her going

Let me chime in on the carb cleaning thing here. I am a new forum member/Seca owner, but from a completely frustrating experience I had with a previous project, a '96 Kawasaki KZ1000P, during which I made every *noob* mistake you can imagine with the carbs. I ended up taking them on and off no less than five times, all with a stock airbox.
First, breaking the carb rack... I would *highly* recommend you do that, the hardest thing about it is getting the rail screws out, after that it is all downhill. There are at least two good reasons to do it; first, it is the only way you can access the fuel rail O-rings, which after several decades will be like small round pieces of beef jerky. The other reason is to check the butterfly shafts, if they are loose and might need rebuilt, a couple of mine are and you would never know this otherwise.
Don't even waste your time checking the floats in side the bowls, do the "wet" level test with clear tubing; this is mind-numbingly boring, but its importance *cannot* be overstated.
Cleaning...I would recommend an ultrasonic cleaner, Harbor Freight has a cheap one you can fit one carb at a time in that works well. I have tried all the cleaning methods known to man, and nothing works better.

 

Because your fuel rail o- rings are dried out and they will leak. Your throttle shaft seals are dried out and will leak. You can only replace them by breaking the rack apart.

Here's how to clean them thoroughly:

 

What he said...

 

Oh and one other tip. Far and away one of the handiest tools I have ever bought is a little remote fuel container with its own hose and shutoff valve and a hook so you can hang it up high for gravity feeding. If you don't have one, get one, they are cheap. Then you can leave your tank off while you are tuning the carbs, much easier access. For that matter, after cleaning/rebuild, I will hook the gas supply up to the carbs before I put them back on, for an hour or more, to make sure there are no leaks before I wrestle with the airbox again.

 

There is just too much good information in this thread, you guys are on a ROLL!

 

I use an extra snowblower tank with a shut-off valve and several feet of tubing

 

Snowblower...HAH! I left those behind when I moved out of Chicago, and I hope I never, ever see one again

 

Jeez, Dave! That's an impressive photo you posted here! I'm starting to think my carbs may have to visit your shelter for wayward XJs in the future! I am sympathetic to John Hopkins; I understand the basics of cleaning the carbs, but I fear that if I take them all apart, they will NEVER get back together again! I'm referring to it as Humpty Dumpty Syndrome.

 

Welp I came this site for advice and id be a fool not to listen to it. I'm dedicating the next 8 hours of my life to this carbs leaning thing. I'll post a pic when I'm done and hopefully I'll meet this forums standards hahaha.

 

I do have Humpty Dumpty Syndrome hahaha

 

Cleaning Carbs Round 2: this time it's personal.

 

That's better... Now clean EVERY SINGLE PIECE. Don't forget to disassemble the slide assemblies and clean each piece of them too. Don't worry, we will be here to help you reassemble. Now that you have them apart, get new throttle shaft seals, fuel rail o-rings, fuel valve assemblies, gaskets, bowl drain o-rings, and mixture screw o-rings and washers.

Now clean every carb body so meticulously, that every passage is clear including the brass pickup tube. Spray must go in one hole and out another till every hole has been cleaned and blown clear with compressed air.

Don't forget the tiny jet in the bottom of the well in the bowl.

You're off to a much better start this time....

Ask any time you get stuck or nervous.....

Dave Fox

 

Update: Finally my 80 bucks worth of rubber showed up. XJ4EVER was probably the best customer service I've ever had from a business which was really refreshing. I had a lot of questions and they answered them in detail and in a timely fashion. USPS sent my package from Georgia to Maine though just to send it back to NJ..... But whatever its here now and I instantly learned the hard way that I should've had all my parts ordered BEFORE I took the carb apart and let it sit for a week. I took pictures and some notes but its just hard because you don't know what you're going to forget when you go to put it back together so the pictures aren't really a fool proof way of making sure everything goes back together. The only thing I'm really nervous about is the throttle linkage. Everything else is fine, the internals, the choke circuit, fuel rail ect. But as far as the linkage goes my pics just aren't good enough.... Im definitely gunna need some help on it for sure. If anyone has like a step by step rebuild of the throttle linkage that would be amazing.

 

Finished cleaning pic:
Looks about the same as the last one but there is probably 6-8 hours of strictly cleaning every spec of every part. Sending it through the ultrasonic cleaner and cleaning it again.

 

Actually that is the same picture hahaha, I don't know where my finished, cleaned parts pic went but you get the idea hahaha. It was a lot of work.

 

http://www.xjbikes.com/forums/index...-taking-apart-carburetors-lots-of-pics.48063/

This is a great break down. He did a MUCH better job taking pictures hahaha. lesson learned.

 

I would've thought if you're a novice at this, then it would be best to do one carb at a time, that way theres no danger of mixing up the parts. and if you get stuck on the rebuild, you can copy of one of the complete ones.
"just sayin"
stu

 

It really isint the individual carbs that have me trouble it was the throttle linkage and I actually got it figured out pretty quickly. It started right up too!! Also, wet setting the carbs was a huge pain in the ass. I got soaked in gas. Soaked. But it was worth it. I still have a little tuning to do but it really runs well right now. Now I need to save for tires asap.

 

This was my wet set setup hahaha.

 

There you go. And now you're the local carb expert. Pretty tank..........

 

So after a few rides and maybe a total of about 100 miles I think I have a stuck float issue. I drove about 30 minutes to our local watering hole, had some food with my buddies and when I went out to start her back up... Nothing. Took the plugs out and they were black. Even had some gas dripping from the air box drain?! Decided then to have my buddy drive me home, got the pickup and loaded the bike up. Now I've got gas in my oil (again) so that needs to be changed and she really didn't wanna start the next day either. Then me and the old man were messing with it (cleaning the plugs tapping the bowls and opened the air box to see how gas was getting in there) turned it over and it started right up no problem. Didn't take it for a ride but started it another 4-5 times througout the day and it started right up. Stuck float symptoms right? Just confirming. Also my colortune came in today!! Excited to check it out

 

Also my carbtune is on it's way but my old man said I could just set the main idle screw kinda high, then turn the other idle screws one at a time until the rpms raise and back the screw off a bit. The. Lower the main one back down. I still wanna get it dialed in but you do you guys think about this way to do a dynamic tune? I thought it was pretty smart actually lol.

 

Your old man is smart in the ways of tuning a multi-carb engine by ear.
You could have a sticky float, or there could be crud from the tank finding its way between the needle and seat. Fit a small inline fuel filter to keep that from happening. Chacal sells some that fit without cusing any fuel line kinks.

 

it's called the lean drop method if you want to look it up, your "old man" is pretty smart

 

Hahaha it's just funny cause he only had a few dirt bikes when he was younger and if you asked him if he tried a "lean drop" method to sync the carbs I doubt he'd know what you're talking about. I'm all numbers, numbers, numbers, tools, tools, tools and he's the exact opposite. All oldschool. It's always fun working on stuff with him though. Sometimes I'm just like "no WAY that's gunna work" and sure enough..... Hahaha.

 

I actually added a fuel line in for that reason. Just a sears in line for like lawn mowers though nothing special. It gets the job done I think though. I have a sneaking suspicion my bowl levels are off though. I checked the two outside ones with the carbs on the bike and they seemed about 2-3 mm lower then they should be. Might be taking these bad boys off yet again!!! If still rather work on a bike then lean over an engine bay for hours that's for sure!

 

tools came in my colortune plug and sync pro calibration kit. im excited to try them out. I took the carbs back off and found the real problem behind my issue: The emulsion tube on the #2 cylinder unscrewed from the main jet and was stuck to the needle and would rise and fall with the needle!!! im glad I pulled them off. I also re-wet set the carbs the right way and I think someone gave me a bum steer on the forum. Some one told me if the bowls leak from the gasket when you take them off (from being full to the brim with gas) then the floats are set to high. But its literally impossible to get the gas 3mm from the rim and not have some gas seep over the rim. So I reset them and really dialed them right onto the 3mm mark. It started right up instantly and runs way better. Ill let you guys know how the colortune and syncpro goes tomorrow. Well see how close my old man was hahaha.

 

You'll be amazed at how much better it runs once it's synched and then colortuned (hint: for beyond-the-call-of-duty results, re-synch the engine immediately after adjusting each cylinder with the colortune).

 

did you get a yics block off tool? you will need one to get the tune right.

FU

 

Will do!! I actually warmed the bike up before and stuck the colortune on it just to see and I'm wondering what exactly I'm looking for. I know orange or rich, blue is lean but what is perfect? I'm thinking it's right as it turns from orange to blue. Also when should I adjust it? At idle? Or at a certain rpms. I also noticed that when I rev it it gets super orange which makes sense right? Haha i don't know I'm new at this.

 

White is lean. Bunsen blue is spot on.

 

Yes, orange/yellow is rich, blue is JUST RIGHT, and white (or no flame) is lean.

Correct!

.

Correct! And ONLY at idle (1100 rpm's ro so). Don't rev the engine with the Colortune installed!

You shouldn't do this, but............it should go rich ("super orange") just for a few seconds, and then return to blue.

 

Do all xj's have YICS? I won't be around my bike until later this afternoon but I don't think I have it. (I also don't know what it looks like or where it is hahaha) but I just don't remember seeing anything that sounds like YICS or where is put the YICS block off tool. I'll do more research tonight

 

I forgot your bike is an 81. I believe your bike may not be a yics engine. if it is a yics engine, it will say yics on the valve cover and the side covers.

FU

 

Oh ok then no it's definitely not. Thanks for the info though! Always learning about these bikes