Common Technical Issues: YAMAHA XS400

BRAND: YAMAHA
MODEL: XS400
YEARS: 77-79
CATEGORY: MOTORCYCLE

TECHNICAL ISSUE DETAILS
Yamaha XS400 models have an excited field type alternator system. The field coil inside the alternator is fed from the regulator, the other lead to the field coil goes to ground. This system basically works just like a car alternator with a field coil that is switched on and off by the mechanical regulator depending on charging voltage. Battery charging problems on these models are typically caused by: 1) BAD CONNECTIONS. These bikes are fairly old and you will need to ensure each and every electrical connection is good. 2)The OEM rectifier is OFTENTIMES bad. You can replace both the rectifier and the mechanical regulator with our single ESR350 regulator/rectifier which is a plug in single unit replacement for both original units. Testing procedure for diodes in the rectifier: Diagnosis Center

PRODUCTS AVAILABLE FOR THIS VEHICLE
See products available for the YAMAHA XS400, 77-79 MOTORCYCLE.

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