Scooterotica

I have just had my frame welded on the front where there was som pitting.
Does welding weaken the frame a lot?
Obviously i know that heating and cooling metal is not good.

Probably nothing to worry about, but there is welding, and there is welding. If the whole front of the scooter was glowing red hot while using acetylene (a hard thing to achieve as the frame is a great heat-sink), then there is more likely to be an issue, but you are unlikely to have a problem. Steel is very much more forgiving that ali when it comes to heat.

I'm not a metalurgist, so if someone else has an opinion, please feel free to contradict me.