carb balancing?

[nick crisp]

When I've balanced carbs in the past, I've just been concerned with getting a level reading across all four, and didn't used to worry too much what that reading was. With wear and tear on higher mileage engines, I believe it would become more difficult to ensure that the actual reading would be perfect anyway. The goal is to get the bike running as smoothly as you can and not worry too much about whether or not you are perfectly "on spec". Obviously if you are no where near the recommended settings you may have another problem, but this would probably manifest itself in other noticeable symptoms anyway. I also seem to remember that you usually have one "reference" carb, and I seem to remember that this one doesn't usually respond in quite the same way as the other 3. But it's a while since I've done this myself, and perhaps my memory is a little cloudy.

Actually, come to think of it now, on some bikes the reference carb is not adjustable?