I have been watching this thread to see which direction it would take as more information was provided.
First, I don't think there is any way that the DPS unit itself can produce a chirping noise. We've had a number of bad DPS units (I've gone through 3 myself). We've never encountered any noise coming from the DPS unit.
However, I can confidently say that the DPS puts a heavy load on the battery when engaged at stop or slow speeds, and therefore, places a heavy load on the charging system. You just started the engine, placing an initial drain on the battery which the alternator is already working to replace. Now you are turning the handlebars and this additional demand on the alternator does exactly what
@jcthorne stated.
The alternator has a set of friction disks which are designed to slip if demand exceeds a certain amount. This will definitely cause the chirping that you describe.
But I will go one step further. Why did BRP design the alternator system this way? As far as I know, this is not a common approach. Charging systems are typically direct drive with no such slipping system. I'm hoping someone will correct me if I am wrong here.
My BushHog has a similar system. It is designed to slip if I hit a rock, a stump, or something that would otherwise damage the gear box, or bend/break something. But an alternator? This indicates to me that BRP is worried that gears, a shaft, bearings, or an electrical component could fail if overstressed.
Increased loading on an alternator is not like hitting a stationary object with a BushHog. Even heavy loads are not going to instantly stop an alternator. So, the only thing I can think of is that there is a weak link in the system somewhere. And these friction washers are a less expensive solution than upgrading the system to handle the output capabilities of the alternator.
This is my speculation. What's yours?
