midi sync

i have a mpc 4000 and a yamaha motif. the problem im having is whenever i try to record a midi track with i.e. strings when i hit the rec and play buttons it changes the sound to another sound.

Put your Motif in MULTITIMBRAL mode (ie 16 midi channels).

Has nothing to do with midi sync as your title implies.

I don't have a Motif, maybe someone can chime in with the exact procedure?

Otherwise its in the Motif manual.

in the sequence .Go to the track that you want to use for the motif. Then change the type to instrument (instead of drum - not sure if you have to do this but Ido anyway).
then chose the out section and change it to the midi output (Ie midi out-a) you are using to send to the motif - then you can go up to the pgm change window and find the patch you are using on the motif (scrooll through as you watch the motif's display until you hit the one you want)- then everytime that this track plays it will use that motif patch. When you want antoehr motif part use a different midi channel (like channel 2 instead of 1) and select the next patch sound using the pgm change.- hope this helps

Also, I think the 4k needs to be switched from a drum track to instrument track if I'm not mistaken (in seq mode of course).

Nah just hook the midi outs and ins up (motif to mpc and back)

and select the channel you want it to send midi to

in the OUT 1 or OUT 2 part on the main screen (can be done per channel)