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82 jx650 carb issue


Sir Puma
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Ok, oh bike gurus, it's been cool and rainy all spring and into summer and frankly I haven't been riding much. But now that we finally have some sunny warm weather I want to hit the road and my XJ is being a skank. First, I can be out running like a top then it will act all starved for fuel. But when I put it on PRI she'll run OK. So today I pulled the tank and carbs and cleaned them out. Got some bits of rust and stuff out of the tank and cleaned off the filter screens for the fuel cock. Pulled the carbs mostly apart and cleaned out the primary jets and bowls. I run around the block a bit and it runs like crap. While looking it over I discover that #4 exhaust pipe isn't very hot. I clean the plug and check for spark and it's getting plenty. I unscrew the little plug on the bowl for #4 and fuel pisses out. So the carb is getting fuel and the cylinder is getting spark. But the plug is dry and I don't think it's getting fuel from the bowl into the cylinder.

My next step is to pull the carbs again and completely break down #4 and clean every part I can pull off. Sadly this will mean I have to sync the carbs again. Anyone got any ideas where to look first?

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Ok, this is starting to really bug me. I pulled the carbs off and there's fuel in the intake area. The reason I thought no fuel was getting to the cylinder is that when I pulled the plug wire while it was running, there was no change in RPM or how well it ran. When I pulled #3 it sputtered and stalled.

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I'm surprized no one commented. Anywho. I went through the #4 carb and I think I had the Pilot jet and Main jet swapped. One has a very tiny hole and the other big. I'm not positive, but having got through it and made sure the bigger hole was on the main jet I just test ran and the exhaust is getting proper hot and when I pull the plug wire the engine loses some power. I hope that was why my engine would ocasionally act like it was starving for fuel.

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More on my diary of doom. It ran a bit rough this morning but once I had been riding a bit it smoothed out. Ran fine this afternoon but at one point I had to get on it to merge with traffic and it started running like crap. RPMs were jumping around and it was sputtering and acting both like it was starving for fuel and missing the firing order. I could sure use some help.

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Reading through the manual it talks about this kind of issue also being related to ignition. It describes two tests I can do on the ignition coils, testing the resistance between the spark plug wires and between the wires the come from the electrical system.

*edit*

I'm a dork fish. I'm getting the correct reading (once I set the multimeter on the right setting). Now I need to pull the tank and test the other leads.

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I'm surprized no one commented.

Generally happens when no-one knows about your particular bike.

No 4 cylinder problems is apparently indicative of poor insulation on the ignition coils, as mentioned in your other thread about those.

If you've been getting a fair bit of rain/wet/condensation/whatever lately, that could be one cause.

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I live in the Pacific NW. We have two dry months out of the year, the rest of the time we have a varying degree of rain. I did the secondary test on the coils and got the right reading. Now I have to pull the tank and measure the other leads. Then if that is good I'll need to look at the pickup coil. I may have to make a vid of how it runs. I would think anyone with general 4 cylinder motorcycles would be able to help figure this one out. I sorted out #4 not running right (had the two jets in the carb bowl swapped) but now after running fine for a short time it runs like total crap. I may have to resort to taking it to the shop which could run me more than what the bike is worth.

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I live in the Pacific NW. We have two dry months out of the year, the rest of the time we have a varying degree of rain.

Which tallies with general reports of the coils having bad insulation and being susceptible to failure around the times when it rains. Liquid tape is the common solution, as mentioned in your other thread.

DC1-1 Dyna Coils.
$160 from JCWhitney.

I would think anyone with general 4 cylinder motorcycles would be able to help figure this one out.

What are you saying - We're all retards because a problem commonly reported by other owners of your specific bike model is vaguely related to other completely different bikes, simply because they all have 4 cylinders??!! :lol:

All Dragstars have 2 cylinders, yet the frequent issues with each individual model are not common between different models and engine sizes. Then you have different manufacturers of Cruiser, with their own set of common issues. Then all the other twin cylinder bikes, V-twin and otherwise.

Infinite diversity in infinite combinations, mate.
This is what Google is for. ;)
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What are you saying - We're all retards because a problem commonly reported by other owners of your specific bike model is vaguely related to other completely different bikes, simply because they all have 4 cylinders??!! :lol:

 

No, what I'm saying is that troubleshooting ignition or carb issues is the same, no matter what type of bike you have. Check this, if not check that, etc. The manual will tell me how to check and what to look for but I didn't have a clue where to start. I'm not a bike mechanic but many on here are and a little advice would be much appreciated. Google netted me squat.

But all that is neither here nor there as I think I may have fixed the problem. In preparation to checking the other leg of the coils I motored it onto my front porch with much complaint from the bike. I got it up on it's stand and started again. While pulling the seat the bike just up and cut off, wouldn't start again. While poking around the small fuse panel I found one loose wire that when jiggled would elicit a clicking noise from under the fuel tank (coils?). After playing with it the bike started and ran smooth. Pulled the wire off and bike died, no starter. I tugged on the connector and it came off with ease. So I replaced it and cleaned up the end of the wire. Runs good, for now. All that remains is some longer test runs and keep an eye on it.

Had someone replied with a simple, "check your fuse wires and the wires going to the various components" I might have caught it early. I should have thought to check the wires for secure connections.

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Well we're not all utter gurus here and certainly not guaranteed to magic up answers within the 24 hours it took you to expect an answer.

Knowing nothing of your bike, I did a quick Google and in about 4 minutes had several sites all in the US that offered at least a starting point that was related to the ignition issues your explanation suggested, even though it was fuse related anyway.

On behalf of the entire forum, I offer our sincerest apologies for not resolving your issue sooner and promise to try and offer a better service next time.

Sense of humour optional.

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On behalf of the entire forum, I offer our sincerest apologies for not resolving your issue sooner and promise to try and offer a better service next time.

Sense of humour optional.

haha and thats the polite response

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Puma you only come here when you have problems, also the threads some times move fast and no one see's the older ones ,NOTE this is NOT a repair info site just a bunch of guy's and gals who like bikes.

The last thing I would have suggested was that you had the jets in wrong,not even sure how you managed that or synced the carbs, and things like loose wires are mostly only ever found by looking at the bike yourself. Not by me or anyone else helping from here. If it's a common problem with you spefic bike then only someone with that bike would probably know.

The only general solutions are

1 spark

2 fuel

3 compression

4 dirty carbs/incorectly set up.

After that then it starts to be bike specific ,any bike ove 10 yrs old should have the entire wireing system completly checked for green death and loose wireing bitching about not getting help is counter productive.

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In 4 minutes I'd ascertained that yours is an American model, there were several faults common to that bike, the coils were the most likely common fault and in keeping with your description thus far, the best-rated replacements were DC1-1 Dyna Coils and that there's a helpful US-based owners forum specific to your bike range at XJBikes.com.

I tried to help...

haha and thats the polite response

I'm trying to be a nice Tasky these days...

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On behalf of the entire forum, I offer our sincerest apologies for not resolving your issue sooner and promise to try and offer a better service next time.

Sense of humour optional.

Well then, please accept my most sincere apologies for asking for advice. I'll do my best to not offend you again.

Sense of sarcasm optional.

And, yes, Ttask, I have a US XJ650J, thanks for pointing me to XJBikes.com, I'll yank their chain for a while now.

The problem I thought may have been Coil related turned out to be a lose wire. Go figure. But I'm still having carb/running issues. Lots of popping and spurting while under power, though not at idle. I've got some parts on order and will be going a complete teardown and clean, adjust the floats, then synch the carbs. One thing I hadn't gone over before was the pilot screws. I didn't want to mess with the mixture. But I'll follow the manual and try to fix this thing. Hopefully that'll do it. If not then it's off to the shop. I just don't know how much that would run. Ugh

dt502001, I come here to seek advice from people who are way more experienced in motorcycles than I. As I don't have gobs of money to spend at some school to learn the ins and outs, I choose to seek advice from folks who I see as knowledgable in the field. As many riders are forced to work on their own machines I respect their opinions. Sure I don't hang out here and chit chat about all kinds of stuff, but that's because I don't know anyone here and already frequent a dozen other forums and even manage one. I'm also a private business owner/self employed and rarely have time to hang out on forums.

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Well then, please accept my most sincere apologies for asking for advice. I'll do my best to not offend you again.

You can ask, by all means. That's what we're here for.

But sarky comments about how no-one has commented within 24 hours of your post does not inspire us to respond, especially as many of us are just as busy with real life as you and none of us do this for a living.

Be patient.

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