Yes it is a heavy engine. I would really like to delete the balance shaft. It would be a easy 6-7 pounds weight loss. I have heard that it will shake pretty bad. I will try it. And see how bad it is. I have ridden, built and worked on many high powerd big twin snowmobile engines and they dont have balance shafts. My car also has the balance shaft pulled out. Its been like that foe over 8 years and makes 600 awhp on low boost! It shakes, but not bad. I will figure out a way to ditch the shaft in the 951. Im just not sure on how much work it will take yet lol once i have ridden the ski with the stock 951, if its what i want, i will work on lightening it up. I will be making the driveshaft out of titanium as well.