20 Most Recent 1983 Yamaha XS 400 L Maxim Questions & Answers

Only a suggestion but when you cleaned everything up did you check to see if there was a screen filter inside the tank? Second suggestion, possibly the fuel pump got gummed up with 10 years of sitting and is only working a reduced capacity that can't keep up with the flow requirements?

What is wrong with them?

my goodness kids do your research. carbs mix air and gas very specifically. any change in air intake will mean you also need to adjust the flow of gas in carbs. even if you use an aftermarket filter in the original air box it will still change the amount of air going to the carb, it might not be as drastic as a pod filter but it is still a change. you will probably need to change the main jets in your carburetor as well as play with the air/fuel mixture setting screw.

Your oil filter is located underneath the motor. There is a round cover 4" to 5" in diameter next to the drain bolt. The cover is part #1 and the oil filter bolt holding it on is part #4 on the diagram. http://www.bikebandit.com/houseofmotorcycles/1983-yamaha-xs400k/o/m8258#sch208022 To change your oil you will need 3 quarts of oil, a filter, and a new aluminum drain plug washer. You can reuse the old drain plug washer if it has not been squished out of shape. Your motorcycle comes from Yamaha usually with 20w-40 mineral base motorcycle oil. You can use any oil that is JASO MA certified motorcycle oil. 10w-40 for cold climate. 20w-50 for warm climate/touring. Car oils use different additives and may cause scoring in certain types of cam bearings. Do not use any oil that says " Energy Conserving " on the label . It will shorten the life of your wet clutch and transmission gears. If you choose Synthetic oils, they will help your bike run cooler and shift easier. Pour in 2.5 quarts of oil to reach the high mark on the dip stick or inspection window. Make sure the motorcycle is upright or on the center stand when checking the level . You will probably need 3 quarts to hit the high mark. Run the motor for a minute or two to fill the oil filter compartment with oil. Now recheck the oil level and top up as needed. If you want to try an inexpensive full synthetic oil that is JASO MA rated 15w-40 Shell Rotella T Synthetic fits the bill at about $22 per gallon. All brands/manufacturers make a motorcycle oil. Some are very hard to find. Just make sure that the oil you pick has the JASO MA Japanese engine Rating to protect your motorcycle engine.

Your problem is a bad kick stand safety switch jump the switch out and your problem should stop.

sounds like a blown globe,,check and replace,,if the globe is ok,you need to inspect the wires from that indicator all the way,for loose connection,or frayed and shorting out somewhere.

Your clutch plates have become stuck together.The clutch needs to be pulled apart,clutch plates cleaned,and put it all back together in EXACTLY(EXACTLY) the same order as it came apart.There is plenty of people that know how to do clutches.Hope this helps

I think it is marked on the engine casing right where you pour the oil in. I believe on that bike it is 3 quarts with oil and filter change

Either 10W40 or 20W50.
I used a good synthetic motorcylce oil but if you want to use regular oil thats ok as long as you change it at its normal time.

Change your plugs first , make sure the fuel is not too old or may have water in it .
Check all connections and make sure the coils are well earth .

Some vehicles have a pressure switch that is subjected to oil-system pressure, which must receive pressure to allow the ignition to function. This guards against lighting off an engine before it has oil pressure.

Sounds like you have one, and you need to crank the bike enough to fill the oil pump and filter back up.

Try removing the plugs, and cranking the engine for a while to get the oil system back to normal, then replace the plugs and start it.

If you do not have such a system I would look for a wire somewhere off to the side that accidentally got disconnected while you were working on the filter.

Check to see whether the bike has spark (Put a loose spark plug in one of the plug wires, lay the plug on the engine then crank to see if there is spark).