It's alive !! It's alive !!

Fired up the ol' XJ750 today. It's the first time it has been started in at least 10 years. Boy did it sound sweet, and surprisingly smooth. Since I haven't got the fuel tank ready for it yet, I fixed up a small bottle and bungee corded it to the front of the seat. Looked funny, but it worked, all I needed was a few ounces of fuel to test her out anyways. All I intended to do was let her idle a little while. After a couple of minutes I heard a nasty grind and she died. By the way it stopped I knew that it lost all spark to the plugs. The only thing I could think of was the pick-up coils because of the grinding sound as it died. Opened up the cover, and sure enough the top coil had come off of its mounting plate. Put in the spare set of coils that I had by chance picked up a few weeks ago. Just bolted it in plugged it up to the TCI, tucked the loose wires in a few places hit the starter and she fired right back up, cool. I let her warm up and rolled the throttle a little and she took the extra fuel with gusto, and wanted more. I was surprised at how smooth she revved up, since I haven't even synched the carbs yet.

She was wanting to get on the road, you all know the call, you've heard it. So I filled the little bottle back up, fired her back up, lifted the kickstand, pulled in the clutch, pressed her into 1st gear, (with a loud clank), well it has been sitting for a long time. Slowly released the clutch and she took off firm and smoothly. Checked the brakes, they were firm and strong. Cool! Let's go for a ride. She shifted smooth and strong. Dang! This thing accelerates a lot faster than my CB750 ever did. And it's not even running at its strongest yet.

The next problem that needs solved is how to re-run the wire from the pick-ups to the TCI unit, the way they are supposed to be. The question is, how on earth do you get the blue wire unscrewed from the bottom of the engine block. You know, the one that runs from the TCI unit down through the harness and is screwed to the bottom of the block right next to the oil level sending unit. Between the frame, the engine, and the muffler you can't get a screwdriver up in there. I even tried to lift the engine in the frame a little bit by taking out the 4 engine mounting bolts at the front of the frame. I guess you have to take off the exhaust to get to it, huh?

Once I get the wire re-ran the way it supposed to be I have to tackle the charging system. The headlight never came on the whole time it was running . So I checked the voltage at the battery, 12.3 volts, even at 4000rpm. So no charge, that'll sure limit my range. Gotta troubleshoot that one soon.

 

A few pictures of your dilema would be great. If you gotta drop the pipes, do it. Just remember to pick up a new set of gaskets for the header pipes or smear the old ones with a dab of orange permatex and torque to spec. The head light could be the relay or the fuse (and maybe something else altogether different). Check the fuse first (should be 10 Amps) and the clips (lots of us have had them break causing intermittent or non function). Looking forward to hearing how much better it runs after your done with the tune up (don't forget to clean those carbs!). Good luck.

 

Went out this morning to do a little diagnostics on the charging system. Multimeter showed that the field coils and stator coils were good on the generator. So I checked the rectifier/voltage regulator, 4 of the 6 diodes failed. So it looks like it's time for a new rectifier. Anybody know of a good source for these? Old Bike Barn has them for $99.95, ouch :cry: , hoping to spend a little less than that. But at least the stator is good, I can just about imagine how much one of those are.

I'll try to get a picture of the blue wire I was talking about tonight when I get home from work. But it is in the bundle of wires that leads from the TCI unit down to the Pick-up coils. It breaks out of the bundle at the same point where the wire to the oil level sender does. The blue wire has a crimp-on wire conector that looks like a "Y". So all I need is to loosen the screw from the block, slip off the old one and slip on the new one, but there just isn't enough room in there for a screwdriver. :? Humm, maybe a 90 deg. screwdriver from my fishing lure box will work. I'll try that tonight as well.

As for the carbs Robert, that was one of the first things that I did when I brought the bike home. A good cleaning and adjusting was very much in order. There was about 3/16 of an inch of varnish in the bottom of the bowls and the jets were almost total clogged.

 

Your blue wire runs to the neutral switch according to the Haynes. The off-set screwdriver sounds like a winner. You might try to leverage it up into the slots with a second screwdriver, but be sure to protect your paint (don't ask). There was a link given somewhere on this site in a forum for a company that makes just what you need. The other folks are PartsAndMore but I have not had anything positive to say about them yet. They don't answer email and advertise stuff they don't have for years!!! Yes, I'm a little miffed (I really want those brushes!!!!). $100 for a voltage regulator is a good price if you ask me. My Ninja ran $148. As far as electrical stuff goes, new is best practice. Only reason I buy used is I know what I'm looking at and how to test it or the price is free. Good luck and let us know how things turn out. I have an extra regulator, but again, everything is buried in storage (and I'm not kidding). If I get to it in the next 2 months I'll count myself lucky.