How long can engine oil last in motorcycle?

I just bought a Honda CBR 250r from a friend. He bought it brand-new at the end of 2012, so it's 3 years old now. But the milage is only about 160, pretty low. Most of the time it just stays in his garage, without any maintenance. I've been using it for two weeks since I bought it, and added another 150 miles to it. I wonder if I need to change the engine oil and do some other maintenances now? I also checked the oil, it is full and looks pretty clear.

How long can engine oil last in an unused and brand-new motorcycle? I tried to make an appointment to the dealer and schedule a maintenance but the local Honda dealer here won't be available until a month later.

Oil should be changed at least once a year.

Moisture from the air gets into the oil and contanimates it.
Oil should be changed at least once a year
More often when the bike has been ridden a specified number of miles as stated in the owners manual.

Change it, then you'll know exactly when it was done.
At that mileage it shouldn't need anything else, skip the dealer service.

Best is to change the engine oil
as moisture gets into the oil over time

On a street bike you can go about 10.000 miles or every year.

Heres something oil makers won't tell you. If you change the FILTER a LOT you really won't have to change the oil very often. I change the filter every MONTH. Guess what? The oil stays a golden honey color and doesn't lose viscosity for a very very long time. FACTS! I learned this a very long time ago while attending MMI and talking to an oil company rep who was visiting the school.

You have not even reached the first service interval.

But as soon as you do make certain that you have it done. Because the oil in your engine now is a single grade that is used to help the components mate to each other so there will be some metal shavings in the oil that need to be drained out.

Get a manual and check the exact mileage recommended. Ask the dealer if there have been and recalls at the same time.

Change the oil. Depending on what it is it can start to break down in as little as 6 months. The biggest concern is the water that has condensed in it.

Good practice on any second hand bike is to give it a service straight after you get it home regardless of the mileage since its last service. That way you KNOW it's been done & properly. As others have written moisture gets into the oil, especially if only ridden on short trips so the oil doesn't reach full operating temperature. An annual oil change is usually enough with modern engines & oils & normal riding patterns. Six monthly if ridden a lot. Remember its the short rides that cause wear & oil problems - take it for a good long run ( 1/2 hour min) including some enthusiastic throttle use (once it's run in) at least once a month.