WARNING!
Motorola produces 2 kinds of devices, first is "don't touch me, I know better what you need" and second is "if you're really want it, first read our manual up to the end".
Most well-known Motorola modems are SURFR and CODEX. I'll try to describe shortly them both.
AT&FL1W2%C\C1\N4\T5\V1"O64 OK ATS7=120S10=30 OK
W - responses form.
%C - data compression option.
\C - MNP buffering option.
\N - Connection option (reliable V.42).
\T - inactivity timeout (in minutes).
\V - extended responses (on).
"O - V.42 dictionary size.
This modem is of first kind.
This modem is of the second kind and supplied with the manual that is so huge that I still can't complete any opinion about optimal settings. But I don't think that you have it - the usual application of such modems - industrial leased lines.