Got my batpac and installed it today on my '89 RZ350. For those that haven't heard of these, they are a device that takes place of the battery in most 2-strokes. Here's a link to the site: http://batpac.2stroke.cc/
This thing is super easy to install, it took more time to loosen the fairings and take out the old battery than to hook this up and fasten it down! Even though I'd seen the pic in the ad, I still was surprised at how small the device is. As stated on the site, my headlight is brighter at idle than with my old, weak battery. At a low idle speed, the headlight is not as bright as could be, but when given a little gas (like a high idle), it comes up to full brightness. My old battery was so weak, the turn signals didn't work unless the engine was really revved up, and the tacho wasn't even working properly. With the batpac, the turn signals work at idle (better with a high idle), and the tacho is working again.
All in all, I would say this product does what it's supposed to do, and I am happy with my purchase. I wouldn't hesitate to recommend it to a friend.