Motorcycle Repair: Start Bike after Being in Storage, honda xl250, vent holes

Question
I have a Honda XL250 that has been in storage for more than 20 years.  What do you suggest I do before I start it for the first time?

Thank you!

Answer
David, I am assuming that the engine still turns over..?

Drain the oil, first. I would get a squirt can/bottle with some light oil... 10-30 or so and shoot a few squirts down the spark plug hole, then remove the valve cover caps/cover and oil the rocker arms and camshaft if you can get back to it. Spin the motor over, without the spark plug installed, to help prime up the lubrication system.

You didn't say what year it is, so if it is an early one and has points and condenser ignition, I would remove the point plate and check the mechanical advancer for free movement. If you have to pull it apart for cleaning and lubrication, check the relationship of the point cam to the advancer base. You CAN put it back on 180 degrees out of phase. It will not start, if you do that....
Point plate back on, after you put a little point cam lube on the point cam, then turn the engine over until the points are wide open, as far as they will go, then check the gap. Should be around .014"  Be sure that the point faces are CLEAN and shiny.

Fuel system.... tear it all apart. Fuel tank gas cap vent holes need to be checked, fuel tank must have no rust or moisture in the bottom, fuel valve (petcock) should be removed, disassembled and new rubber parts installed. Fuel line should be replaced, then you get to remove the carb and  see what's inside!

Old gas residues must be fully removed, all jets and passageways cleaned and opened. Float valve needs to be inspected or replaced. Set float level to whatever spec is for your year machine.

With the oil in the cylinder whirled through a few dozen times, you can then put the spark plug back in. Turn on fuel tap, pull the choke ON and hopefully light it up! The clutch may be stuck together, after all this time, so you will have to buy a clutch cover gasket and seal, drain oil, remove the cover (use an impact driver on the screws), and then disassemble the clutch steel and fiber plates. If they are badly worn/rusted/decomposed, then buy new ones.

After that, replace the drive chain, the battery, inspect and clean/lube all the control cables or replace them. Grease any zerk fittings you see around the swingarm.

The fork seals will probably start leaking soon after you start riding it again. Install new tires/tubes, check spokes for proper tension. The brake drums will probably be rusted over inside, so scrub the crud out of them and hope that they are still fairly round. Depending on the miles, you may need new brake shoes...

Do a full function and safety inspection before you throw a leg over it and take it down the road....

Have fun and be safe...
Bill Silver