looking to change gear ratio from 1.5 to 1.36 is their any reason you cant change it in the upper. my upper gears need replaced anyway but lower is fine.

That's the way it should be done. Change upper to 29/27 gears

sorry forgot to mention Lower is an xr and can come in 3 ratios just wanted to know which is best way to go for strength and durability. Thanks for the chart

Just curious. If the boat is already propped to run the 1.5, why would you go up to the 1.36?

The regular Bravo/X lower and the 1.50 XR lower have the same gear tooth count so switching the upper gears in a X is all that is needed to make it a 1.36.

Do you have XR uppers?...I’m guessing yes, since you say your uppers need replaced

thread title says he has a Bravo X and that is what I based my answer on.

bought boat with no drives this is ratio that old owner was using. 30pitch p5 props to answer Keith