I'm a dummy... so teach me about starting a long-sitting bike...

[Jeff S]

In my continued quest to not remain a mechanical dummy...

When a bike sits for a decade, its obvious that the cams, rings, etc will be bone dry... so just trying to crank it up as-is seems a little punishing to those metal-on-metal contact points. For a bike you haven't ridden in a week... obviously no issue...

So, where's the line for you? If your bike sat a year... 2 years... do you just crank it and go? Or turn it over with the kill switch off to circulate oil and build at least minimal oil pressure before running it under power? When would you pull plugs and squirt something into the cylinders before trying to fire it up?

Do I just have an over-active sense of mechanical sympathy? Or do dry bearings and dry cam lobes weigh on your mind when you eye the starter on a dusty relic that needs new life breathed into it?

 

[John Bennett]

so just trying to crank it up as-is seems a little punishing to those metal-on-metal contact

Yes, First pull apart the fuel system and check for varnish. Wash out fuel tank with new fuel. Rinse lines and carb/injectors with spray cleaner.

Pull the spark plug. Spray lubricant in there.

Then, change the oil and rotate the engine many times before firing it up.

 

[Rydah]

Yep, what he said. Make sure battery is good and charged, give the airbox/air filter some love and gap your plug/change it out while you have it out.

 

[Jeff S]

Yeah - I think I know what to do... I'm asking more about when ? Obvious for a decades-old bike... but what about 6, 12, 18 months. How long do parts stay "wet" and how quickly when rolling by hand will oil actually reach cams and all the oil passages?

 

[John Bennett]

How long do parts stay "wet" and how quickly when rolling by hand will oil actually reach cams and all the oil passages?

It would help if you told us how long your bike as been sitting.

I've started engines that clattered and smoked from dryness after sitting for only 6 months.

Whether avoiding that Labor is worth the risk depends on how long it's sat, and your financial situation.

 

[dukey33]

Yeah - I think I know what to do... I'm asking more about when ? Obvious for a decades-old bike... but what about 6, 12, 18 months. How long do parts stay "wet" and how quickly when rolling by hand will oil actually reach cams and all the oil passages?

6 months I would say no problem. Send it.
At 12 months I would want to do a bit extra care & feeding before hitting the button.

When rolling by hand, it is unlikely to get spinning fast enough to get the oil pump primed and pushing oil to the top end.
I had a shop teacher instruct me to pour oil into a new engine over the valvetrain and all the top end; then use a power drill to prime the oil pump until the oil comes up. A previously run engine won't be as dry as a new engine so hand rolling a few times and then going to the starter would be okay.

 

[Big Block]

It depends on the humidity, dust conditions etc. where it was stored IMO. I live in a dry climate and my old bikes are stored inside. I leave them 6 months without worrying. In a dusty climate, wet climate or stored where there might be critters is a different situation with more care needed.
I drain my carbs when parking for more than a month. But it is still a crap shoot if they might need attention or not. I store with a full fuel tank too. There's lots of factors and no right answer.

 

[Thrasherg]

I remove the spark plugs and then rotate the engine with an electric drill and a socket on the bolt that holds the alternator onto the end of the crank, I keep turning the engine over in short bursts until the oil pressure light goes out. Then I do a few more bursts with the drill, refit the spark plugs and try to start the enigne. I always change the oil and filter before starting any of this and replace any gas in the tank. As stated, if the vehicle has a carb, I try to drain it before laying up the vehicle, either open the drain screw on the carb if it has one, or turn off the gas and run the engine until it dies,