General Help Getting The Old Girl Going. 1983 XJ750

Hello all, Just wanted to say thanks to everyone who contributes to this forum, I have been lurking the last couple of months, and happily surprised with the love for these model bikes. I picked up a 1983 XJ750 the day I turned 16 in '91 with 800 miles on it and rode it on and off throughout the 90's until I got married and had kids and the wife said no more, too dangerous. Well I got rid of the wife, and pulled the ol' XJ out of storage last week and am ready to get it going again. It's been sitting for nearly 10 years. Was hoping I could just put up a few questions now on then on this post and any help would be appreciated.

The first thing I did was pulled the carbs this weekend, gave them a good boil, and cleaned them up pretty good. The float needles were the dirtiest and stickiest of everything, and it went fairly well. It certainly was a grueling job, but glad I did it myself, learned allot. besides wishing I had been a little gentler with the brass bits, and for the life of me not being able to get this light film off the bowls it went well. Tonight going to flush the tank with diesel fuel and some nuts and shake the hell out of it, but the tank looks pretty good. then change the plugs and all the fluids and recharge the air filter.

My main question is this at this point. My plug wires look strange and in the wrong order to me, though I may be wrong. From the position of sitting on the bike, the labeled plug wires are in this order. #1 is on the far left cylinder, #2 is connected to the inner left cylinder, #3 is connected to the far right cylinder and #4 to the right inner cylinder. #1/#4 coming out of the left coil, #2/#3 coming off the right coil. Does that sound rite?

Also, I know my back tire needs replacing, but my front one has maybe 100 miles on it, but has been sitting for 10 years, is that tire safe, or should I replace it. I don't see any cracking and it was always stored inside. Anyway, thanks everyone in advance for your help, and I will try and pay it forward.

 

1 check back brakes for delamination
2 toss that old rubber away (dry rot)
3 ASAP and/or when can afford replace front brake lines, rebuild master cylinder and obviously bleed system

Others will chime in with other crucial items to do to your dust collector err been sitting bike

 

I will heartily second the brake admonitions listed above and tossing the old tires. Not worth the risk.

If it's been sitting awhile you might want to top off the oil and see if there are any leaks - seals and gaskets have to be pretty old. I'd also recommend digging back in the engine crannies and making sure there isn't any detritus lurking back in there . . . first time I rode my "barn rescue" Maxim a large clump of oil/gasoline soaked leaves made the bike catch fire underneath me, leading to consternation.

I'd also tell you to get a new battery, hook it up, then take a wooden dowel and poke at the wires throughout the bike's frame (gently) with the headlights/signals going. You might find out about some electrical gremlins/exposed wires before discovering this on the road.

It's a great bike, definitely worth the effort.

 

The cylinder numbers are 1,2,3,4.
#1 is to the far left and #4 is to the far right. So just follow the numbers on the labels, which means that you should switch #3 and #4 if i understand you right.

 

That's what I thought. They must have gotten switched at some point in storage, maybe even ran that way for awhile because I noticed when cleaning the carbs that #4 carb was twice as dirty as the other three, not sure if that would cause that or not though.

 

My bike has 1/4 on left coil and 2/3 on re right.... which is correct per factory manual.....

 

Thanks guys, that really helps. Anything special I should do with the petcock? I have it off to clean the tank, and planned on just rinsing it out good with diesel fuel. And now that I look at it, what setting should it be when running.

 

Oh yea.... to answer the rest of your question

Compression test
check frame for rust/failure
Factory manual
Chuck the tires
replace rear brake
rebuild mc + front brakes
New plugs
new fuse box
New battery
check electrical for hidden gremblins as suggested above
valve shim clearances
Clean carbs + replace rubber (search for "the whole nine yards"and "in the church of clean")
throttle shaft seals

This is just a basic list.... if anyting else looks suspect ... id just replace it

 

Replace the petcock to tank gasket since you took petcock off...

Consider upgrading original fuse panel before attacking any electrical gremlins.

 

Uh oh. Just changed the oil, and I could tell rite away it was way to water like and far too much of it. Looks like atleast a couple of quarts of gas was in the engine. Any ideas what would cause that? Gas getting past the petcock or something from sitting? Looked clean though with no metal bits.

 

Two problems:

1. Petcock is probably not shutting off properly when vacuum is removed (engine is stopped).

And

2. (The main issue) Float levels incorrectly set, or, more likely, one or more float needles not sealing properly.