I purchased one of these from HArbor Freight and for $10 w/coupon, its perfect for this.When I used the BM governor kit to change my shift points, I used just the weights. Kept the factory springs. It took 2 tries to get it right. I weighed the factory weights. Then each weight in the BM kit. I made one change, compared the full throttle shift rpm gain to the number of grams I had lightened them from factory. Then calculated the next change I had to make. Next test it was bang on. 5900 rpm 1-2, 6100 2-3.
If your peak power is at 5300, you should be shifting at around 5800.
1000 Gram Digital Scale
I measured the weights that were in the governer and both were about 12 grams. I swapped one for a 10 gram weight.
I would have guessed wrong on the weights for sure if I didn't have the scale because you can't just go by the shape. The weights are different thicknesses too.
I need to take it for a test drive so I'm not sure where i'm at. I'll report back.