Modern Vespa

Whe have a Piaggio MP3 400 from 2007. A while ago the drive belt, oil, cooling fluid and spark plug were replaced.

I was wondering: after how many kilometers do I have to do this again? Can someone point me in the right direction?

The best direction is its service manual.

Per Piaggio, the MP3 requires a belt service (new belt and rollers) every 10k km/6000 miles.

Some people have gone over and gotten lucky for a while, others have gotten snapped belts and paid for the mess/damage it creates.

The rollers seem far more durable. My rollers have got over 20k km and still look OK with the smallest signs of wear.

Brake fluid service is due every 2 years. Same with coolant. Only G12 spec coolant, you can get it at any VW/Audi dealer.

Brake fluid spec is DOT4 as stamped on the reservoirs of the bike. Motul makes a great DOT4.

Piaggio recommends a oil + filter change every 10K km/6K mi. I do mine every 5K km/3K mi. Make sure you use a motorcycle rated (MA/MA2) oil. I use the factory spec'd 5W-40 oil by Eni/Agip.

Most importantly, have the headstock bearings serviced/lubed at a minimum every 10K km/6K mi. They are the Achilles heel of the entire bike.

well considering it was awhile ago you have to sometime in the future to go.

seriously how can anyone give you any type of reasonable response unless you give out reasonable info first. try with aprox. date and miles that it was done and your current miles.