De-cat vs True Dual
MGS and Rinehart TDS with a stepped header are designed to enhance exhaust scavenging. Scavenging can also be enhanced with a properly designed merge collector (which the stock system is not), which is why some 2-1 and 2-1-2 systems have a repputation for enhanced low end torque. A properly designed true dual system will outperform the stock exhaust system.
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A further comment on true duals. While they have become a custom feature in recent years, in fact the majority of twin cylinder bikes, of all configurations, had a separate pipe for each cylinder until the late 50s/early 60s. BSA/Triumph discovered that by adding a balance pipe torque was increased and every brand on the planet jumped on the bandwagon, including the Japs, BMW, Moto Guzzi, HD, etc.
Any exhaust system with a balancing feature should be better than TDs, but the factory system of 2-1-2 should be better still, due to the way the two pipes are brought together. Either decatting or installing one of the cat replacement pipes should give good performance results. In my own experience TDs lose out on low/mid range torque.
Any exhaust system with a balancing feature should be better than TDs, but the factory system of 2-1-2 should be better still, due to the way the two pipes are brought together. Either decatting or installing one of the cat replacement pipes should give good performance results. In my own experience TDs lose out on low/mid range torque.
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