I had a 1998 XR engine in my XL and though it had the single-gear balancer, once I changed the top end back to the old style with the wider cam chain, I noticed much more whine. It's a combination of the two. A lot of it does come from that balancer gear though, so it's a combination. I thought I would get the full-on whine I used to get from the '83 XL engine (which I love!) but not quite.
1983 Toyota pickup: total overhaul, preservation-restoration in constant progress...
1987 Yamaha XT600 2KF (German)
STOLEN: RED XL600 in Portland
I do heavy-duty textile repair, upholstery, and design/manufacture bags.