Thx for the replys.

I made it on monday thru the Tecate / Otay Mesa border crossing.
There a two thinks to watch out for.

1. You have to clear your customs document (which I needed cause I have a Visa for the US) with US Immigration.
The US Immigration office is at the End of the footbridge where the people come out from mexico to the US.
Don't get shocked or afraid by all the people - just walk in where they do come out - when you are before the US customs checkpoint - just before - turn right at the not named - not signed office - that's the US Immigration office - where you can leave your US customs form or Visa Waiver thing.

2. To clear the temporary import document (so to say to export your bike) you have to go to the US export office. This is as hard to find as the immigration office, maybe even harder.
Hit the Highway Exit - where it says no return to USA (an no return it is) - and go very slow. Just before you the mexican officers - where it says line "nothing to declare" and "to declare" - this is at the end of the footbridge, where people leaving the US, heading to mexico come out, just before mexico- immediately head right - there is a small gate (on car wide) - with an US customs officer - give them the export form - or if you do not have one - as I did - he directs you to a other office some meters away - where the chief officer will take care of you.

All in all took me 3-4hours on monday to clear the US customs - and 15mins to clear the mexican "permito de vehiculo"

da
Lucky