The original 1987-99 (maybe 2000) ST2 bikes came with a 170 form the factory and then later went with a 180. The ST4 came with a 180. Both bikes have the smae rear rim. You can also run a 190 on it without any issues. I prefer a 180 because I keep an inventory of them in stock on my tire rack....
well. it wasn't the regulator, or just the regulator.
bike died again
Ah yes. Probably a stator. The original regulator is in a piss-poor location that doesn't get any air and the OEM regulator doesn't have any fins to help dissipate heat. It was relocated in 1999. If yours is still in the original location under the seat, you need to relocate it. My second, factory warranty regulator was put in the OEM location and lasted less than 4000 miles when it took a dump. Also, there was a recall on the stator spacer on the '97 and early '98. The newer design has a groove to help sling oil on the stator to keep it cool. The old design didn't aid much in cooling the stator and they tended to overheat and fail. With 54k miles on my bike, I am on my third regulator and my second stator, except I think I got a bum stator replacment and will have to replace it again.
On the bright side, a new OEM regulator (specific to ONLY the '97 and '98 ST2 and no other bike) is only $90 new. Originally, I was quoted $800 back around 2002 or 2003. Yes, that is eight-hundred dollars!
Wish you luck with it.
