New XJ owner with a few ?s

I would just like to introduce myself as a new fellow XJ owner, and a new motorcycle owner as well. I've been browsing the forums for a few days and see that there is a wealth of information here, and many knowledgable minds! I hope you guys can help me along my journey into the world of two-wheeled transport!

About a week ago, I purchased my XJ650 with about 25k miles on it. When I initially looked at the bike, it was sitting in a shed, and hadn't been ridden in a few months. After some trying the bike started up,but ran kind of rough and uneven. After a little checking around, we determined that cylinder 4 was not firing. I was assured that it shouldn't be a coil problem since the coils run two cylinders each (as I have confirmed through what I have read here!) He pulled the plug and it was wet with fuel. We cleaned it off and reinstalled it, and the bike ran fine. I ended up not taking it for a ride that night as it was getting dark, and was beginning to snow.

So, I came back the following day, the bike fired up on the first try and sounded great. I took it for a quick spin after letting it warm up for a few minutes and decided it was coming home with me! My plan is to get everything running great, and slowly clean and restore as much as I can over the rest of winter.

I decided to leave the bike at work in the warehouse, since I don't have a nice garage or basement to do my work in. I figured at work, it will be warm, out of the weather, and I'll have access to tools, etc. So, after a couple days, I got around to checking things out. When I started the bike, it sounded rough again, and after a few minutes of warmup, I discovered that the exhaust down-pipes on cylinders 3 and 4 were cool to the touch while 1 and 2 were untouchable. With an IR temp gun, 1 and 2 were about 160 degrees while 3 and 4 were between 60-70, ambient outside today was in the 50s. I pulled the plugs on 3 and 4, both were wet with fuel. I swapped plug 4 with 1 to see if it is a plug problem. When I restarted, the bike was idling really rough,and the temp on 1 was about 70, 2 was 160, 3 was 140, and 4 was still around 60.

So, my question is, are we looking at a mixture issue w/carb and possible bad plug or plugs, or do we possibly have a ignition coil problem?

I didn't have a multimeter today, but I will bring one with me tomorrow. I also noticed that the boot on plug 4 has a white NGK stamped on it, while both coils appear to be original and have the same stampings on them.

Also to bear in mind, I was told by the seller that the PO had the carbs cleaned and adjusted about a year ago, I have reciepts showing so, but who knows what the shop did or didn't do.

I apologize for the novel I have written here, but I would like to thank you guys in advance for any help you can lend me. It's just annoying to have the bike running fine one day and not the next. At least I have a few months to work these things out!

 

Top off and fully charge battery; check air filter to be sure it isn't a million years old and all "soggy;" if you suspect the gas is old, drain it, install in-line fuel filter; install brand new spark plugs (check all 4 plug caps to be sure they're screwed securely onto their wires) and see what happens. If the intermittent spark thing keeps happening you're going to have to start wringing out the wiring. Invest in a service manual immediately. And welcome!

 

Clean & adjust the plug gaps, switch the plugs around & see if the problem follows a plug.
& welcome, never mind the long description, I was doing nothing this arvo, anyway. Wiz.

 

welcome, I recently had spark problems as well it turned out to be a bad coil ( see your sevice manual for testing) but also a bad boot (which is likely why you have one ngk boot now so be sure to test the boots seperate from the coils it would have saved me a bunch time not to mention cursing!

 

Welcome aboard Pederacer!
I'd also try running some Seafoam in your gas for awhile to help clean up the fuel system. It's clears the gummy stuff out of the small journals in those carbs and the jet passages clear up too. Just a thought.

 

Welcome.

I'm no pro, but everything stated above sounds good to me. I'd replace all the regular maintenance parts (filters, plugs, etc). Test the connections and coils. It might be a good idea to take off and clean the carbs at some point this winter (since you won't be riding it much). It'll help you get more familiar with the bike, really making it YOURS. Sounds like it could very well be any of the suspicions you listed, best to test them individually.

First thing to test, make sure that battery's performing as it should. The bike's sensitive when it comes to using and charging the battery.

 

hey pederacer what part of SW Virginia you be livin in.

 

The test for an Ignition related Problem are easy enough.

But, because the central issue is that this bike has done time sitting around ... I'd go out on a limb here and say the bulk of your troubles will be cured when you have overhauled the Carbs.

However, the bike is within that SET of Bikes which all have the same problems leading to you is troubling you.

So:
Check the Alternator Brushes for being within specs.
Remove the Fuse Panel and replace it with a modern one.
Clean all the Electrical Connections and Ignition related Switches.

Remove and thoroughly clean the Carbs; giving the Carbs a 100% going-over.
Clean all the parts. Remove all the Jets and Emulsion Tubes. Flush all the AIR and FUEL Passages.

Re-finish and Polish the Diaphragm Piston Bores.

Get it all done by Easter Sunday!
That's plenty of time; right?

 

Update time!

I pulled out the trusty multimeter and discovered that I either have a bad secondary coil or a bad wire on one coil. Depending on the cost, I might just replace both coils to have a little peace-of-mind.

I think I will take all the advice you guys are giving me, starting with the carbs and then moving on to the charging system. Looks like I need to start a shopping list!

Fongdingo, I'm in Christiansburg, which is just outside of Blacksburg.

Thanks for the advice guys!

 

Welcome and good luck. As Rick says, a good clean set of carbs will do wonders for these bikes. Also, change all your consumables like plugs, filters, even the plug cables if they're looking bad. You can replace plug cables easy enough if you buy the XJCD set. There's illustrated instructions for doing all kinds of stuff you'll never see in the official manuals.

 

Rick is too humble:
http://www.xjbikes.com/Forums/viewtopic/t=2908.html

here's where I started:
http://xjbikes.com/Forums/viewtopic/t=9 ... r+oil.html

Also being a new rider I did not even know my forks were dry, much less that they were supposed to have oil in them!

My other issue was rear brake delamination -- scared the bejesus out of me -- so I put new shoes in both bikes just to be safe.

Look for chacal -- he sells every part under the sun, fast shipping, cheaper than local (oops, did I say that?)

Double ditto on the new fuse box -- get it from chacal and do it first. Can cause weak spark, which *could* cause your symptoms (doubt it, but could). Causes all sorts of electricals, tho, so just do it first!

Did anyone mention valve clearances? They wear tight, so best to get that sorted early as well.

Fabulous bikes, fabulous forum. welcome!