For the 1973 DT1 the factory manual is LIT-11613-08-01, written across 1971 to 1973 and covering the DT2, DT3, RT1, RT2 and RT3 in addition to this machine. Its code is DT1.
A shared book of this kind is organised by system rather than by model, with callouts identifying which bike a given figure belongs to. That suits the DT and RT range, where much of the engine and chassis work is common.
The useful pages are the specification and procedure ones: teardown order, wear limits, assembly clearances, jetting and ignition data, torque figures, wiring diagrams and symptom-based troubleshooting. Match the DT1 code before you rely on a number, because the range covers several displacements and the figures are not interchangeable.
