yamahas dcs and the aftermarket

AmSnow Riders Club Member SRX102 recently asked us whether Yamaha's new Detonation Control System (DCS) would work with aftermarket heads. We didn't know, so we asked the experts at Yamaha. Here is the answer from Mr. Hiro Okada, THE man behind the DCS development & testing:

"The detonation signal, frequency and cycle shape do not change so greatly with the engine specifications, so the DCS system should sense the detonation even if there has been some engine modification.

"The main point is that the detonation sensor is calibrated between 6500 to 9000 RPM and at throttle openings from just under 1/2 throttle to wide-open-throttle (WOT). The DCS will not work outside of these engine speed or throttle openings.

"In answer to your question, the DCS system will work inside sensing area even if engine is modified. But, DCS system will not work if the engine speed is increased to operate over 9000rpm."

Yamaha spokesman Greg Marier was also quick to add that "as cool as the DCS is, Yamaha reserves the right to review the warranty coverage of SRX engines that have 'blown up' due to modifications."