How much lighter does he think his frame would be over a stock one ?

 

IF i had a ds650, i would go with a new chassis first. If you get the ds650x to lose 100lbs- that would give it the same weight as the rappy700 and the outlaw525. Not only will a 395lb ds650x be much faster than a stock ds650x, it will also be safer because it would handle better and if you do nosedive on a jump and flip forwards, you have a much greater chance of surviving.