How to start my xj650 tear down?

My 82 xj 650 sat outside in the weather for Five years+.
originally stopped riding because the fork needed a new seal...was running very rich though. had new oil, plugs, air filter, then had to tear down the garage and so the bike sat. And sat.
Starting on it today
I removed the seat, old battery, rack and windshield.
Knocked off the dirt with a soft brush.
I'm thinking my next move is to remove the tank, drain the gas. Then prepare for the tank restoration, rebuild or repair petcock, and clean/rebuild the carbs.
Then should I change the oil and try starting, or ???
Thanks for your input

 

While you have the tank off check & re-set the valve shims, get some oil down the bores & around the cam shafts, gently turn the crank by hand (remove the left case & get a wrench on the square nut) do not attempt to start until you are sure everything is moving freely.

 

Yes! Thanks much.

 

Before you go too crazy rebuilding the carbs, etc., you might want to check compression. Make sure it's worth the work.

 

Afraid not, but if you take the above advice on lubing the bores & setting the shims, making sure it's free etc then you can use a car battery and jump leads (if hooked up to a car, leave car engine OFF!) if you don't want to spend on a battery just yet.

I'd expect the compressions to be toward the low end as it's sat so long & will be cold when you test (proper comp test is done hot), but as long as they're fairly even and no big differences between cylinders you should be OK. If you're unsure of anything report back here and we'll be able to advise

 

You should check your valve shims first and make sure that they are in spec. Once they are done you can do your compression test otherwise you may get inacurate results.

 

If the oil is "clean" you can worry about it later,
Other things to note before putting it on the road -
Brake fluid & lines
tires
rear brake delam.

 

Brakes should be FIRST: Anyone can make something go, but making it STOP is what saves your life. Replace the pads and shoes if needed (or if you don't know when they were last replaced) and check the brake lines. Rebuild the front calipers and MC and consider putting new brake lines on if there are rubber ones on the bike currently.

Check motor integrity: Adjust your valves and check compression. Compression should be consistent and around 140+ (someone may correct this, I'm not sure the exact specification). Use the 'wet' check if you get low compression anywhere. Check for vacuum leaks around the carb boots and intake manifolds. Remember the rubber caps on top of each manifold, these can dry rot and cause leaks that are very difficult to diagnose.

Now make it RUN: Clean and rebuild the carbs with all new rubber components, put an inline fuel filter in. Parts here should be around $50 from Chacal. Take your time and do it right the first time - I speak from experience here, it took me about five times removing and reinstalling the carbs before I did it RIGHT and was done with it.

If the bike runs but runs poorly, you can try mixing some seafoam in the gas tank and running the bike for 5 minutes to draw it into the carbs. Let it sit overnight and this may help you get by and clean out any varnish built up - this will NOT fix cracked seals or trapped rust.

At this point you should tune it. New plugs, check the spark plug wires and coils for cracks, shorts, or damage. Tune the carbs - the best method is the use of a Carbtune Pro and a Colortune plug to sync the carbs and set your fuel mixtures. Get the bike to idle around 1050 rpm.

Now the bike works! Put a battery in and decide how much farther you want to go. You may find the suspension is worn or sagging and you may need to rebuild the forks and replace the rear shocks. Check your steering column bearing for uneven feel and repack or replace bearings if necessary. Lubricate and replace any control cables needed (clutch, throttle). Put in a blade style fuse box if not already equipped. Get some good tires on your bike - the ones on it are probably dry rotted.

Post any questions and concerns in this topic you created so everything is in one spot.

Lastly, welcome to the forums. There is a wealth of knowledge here, and plenty of friendly people to help out. I went from a bike in worse shape than what you have to a bike that is a beauty and runs great thanks to the guys here.

 

THis is exactly how I would do it-

Pull the oil drain plug and get the see how the oil looks first. Then pull the spark plugs and shoot some PB Blaster into each cylinder to break the pistons and rings loose. Let the pb soak overnight; it will slowly dribble past the rings and into the oil pan. The next day pour some Marvel Mystery Oil or Seafoam into each cylinder and try to turn the motor over by hand. Remove the left side crankshaft end cover; there is a 19mm(3/4 inch) square nut in the center you can turn the engine over with.
Once the engine is free you can do a compression test, though Id suggest you keep lubricating the cylinders with some kind of penetrating oil and turning the motor over by hand to clean them out from sitting. Everything you put into the cylinders will slowly drain past the rings and out the oil drain plugs

Once you've established compression, you WILL need to disassemble the carburetors and rebuild them properly, replace the front and rear tire(I've had a blowout, trust me you do not want to have a blowout), overhaul the entire front braking system, and rebuild the forks BEFORE you put the bike back on the road.

 

Solid advice especially if there could be dead-tight valves.

 

Thanks! It makes sense to me to lube the cylinders and make sure the engine is turning over. It's been a long time but I remember HATING to adjust the valve shims. I'll have to revisit how to do that...

I have a stage one Dyno kit, again, can't remember what all went into that. But reading here I think I may want to go back to stock. I have an old mercury carb vaccum adjustment stick (whatcha thingy). and I know nothing about the YICS system, so I'm guessing my bike will run better than it did the last couple of years.

Thanks for starting me off in the right direction...Sometime soon I'll be spending alot of time here. Very friendly and helpful people, I think it's going to be a fun.

 

If that bike spent 5 years outside; you have to clean Electrical Connections.

First, ... Install a Brand New Fuse Panel..

Then, ... Get a Can of CRC QD Electrical Contact Cleaner.

It's a Electrical Cleaner that dissolves the oxidation on Electrical Contact and evaporates without a trace.

Buy 2 Cans.
Shoot all the connections on the whole bike.
Especially, ... the 2 Plug-in's on the Black-box ... the Handlebar Controls and every Quick-connect inside the Headlight Bucket.

http://www.crcindustries.com/ei/product ... =03130&S=Y