I had the oil changed last week in anticipation of putting the bike away for the winter. I took it out for a ride the next day and after I returned to my home, and several hours had passed, noticed a small amount of oil under the engine on the garage floor. It made me worry that the mechanic didn't do the job right, but with my knees it is just too hard to get down and look at the underside of the bike. I cleaned up the spot of oil today, took the bike for a short ride (about 8 miles) and then parked it again in the garage. This time, no oil spot on the ground. Could it be that they just added a tad too much oil and it overflowed or something but now is not an issue, or should I be taking the bike back to the dealer mechanic?

Was the oil under the drain plug, or under the oil filter? If under the filter, he may have not cleaned the area up very well before installing the new one, or not tightened it properly.

They likely didn't add too much oil. There is no overflow for the engine. The oil sump is sealed.
What likely happened is that some drained oil collects on a small sump guard around the bottom of the engine. The oil drain plug and the engine bottom are protected by this metal guard. Drained oil will splash onto this guard. It will then drip off the guard for a short period of time unless the guard is thoroughly wiped down, on both its upper and lower surfaces.
Nothing to worry about unless the drips start again.

My mechanic warned me about a few drips after he'd serviced it.

It does breathe a bit after a long, enthusiastic blast along the motorway, too.

Hi,

I agree with bigbird. There is a crank case protection plate under the scooters motor that catchs a bit of oil when the drain plug is removed. A few drops of oil will fall on the floor after the oil change. Your scooter is OK.

Thanks much to all who responded. Makes me feel much better. The SW has been so reliable since I bought it 3 and one half years ago that I would hate to think it was no longer the solid and reliable bike that it has been. Our weather is now down in the 40's in the daytime but I hope to get a few more rides in before old man winter takes over.