I don't normally post on here much, but after my findings I wanted to share.
Earlier this year I installed a 130 front tire on my 99 Venture. The first trip was on back roads and loved the slow speed handling. My first trip on the highway had me reconsidering. It seemed very unstable so I started researching posts to find the problem. I started with the steering head quick check and it seemed to be OK. I was riding with my brother and we got our speed up to around 100 mph and I got into a death wobble. It about 1/8 mile to get it under control. (I don't typically drive like this speed) I then ordered steering head bearings and replaced them. They were bad. I checked the swing arm bearing next and they were also bad so I replaced them. Both helped a lot. But since I wasn't sure about the service history of the bike, I went ahead and replaced both wheel bearings.
I didn't notice any of these problems with the 150 tire but they were magnified by the 130 tire. So for some of you that have tried the 130 tire and changed it because of the handling, you may want to check your bearings closer. I did the quick check on the steering head and swing arm and both checked out but when I tore it down both sets of bearings still had grease on them but when I cleaned the races both showed significant wear. And after replacing, bike handling was much improved.
Wiz