2005 TE450 Stator/Electrical Help

Hello!

Looking for a little help with my 2005 TE450. It has a stock wiring harness, came with no key/enduro kit. I've added a Baja Designs Squadron Sport headlight (26 watts) and TrailTech gauge. I'm using the Baja Designs AC/DC converter (https://www.bajadesigns.com/products/AC-DC-Converter.asp).

The converter has 2 inputs (yellow/white) that are not polarity sensitive, and then two outputs (red/black). Hooks up and seems to work fine, with a significant reduction in flicker.

However, the light noticeably dims as RPMs increase... which if anything is the opposite of what I'd expect. I had also hooked up the lead for the TrailTech to this DC circuit (I thought it said it could it could wired to AC, but the backlight and RPM sensor were acting oddly when it as). RPM sensor works as expected now, but the backlight dims along with the headlight as RPMs increase.

So... I'm I doing it wrong? What would cause that or what should I be looking for? For reference, we just hooked up an cheap LED headlight to a 2004 XR400, converting the headlight lead from AC to DC using a cheap rectifier/regulator and an inline capacitor, and it works with zero flicker or dimming.

Thanks in advance!