......

 

Service manual here is your best friend. Take a look at a couple of videos on youtube to get an idea of the process and then follow the service manual. That's what I did. Easy job.

 

Unless you are the size of a small thai boy then yes, you are too heavy for oem suspension.

On my last ride, I bottomed out the forks at least three times so hard that the tire chewed on the fender. Same in the rear but that is much easier to handle.

Oh and I only weigh 165.

 

eddie, it's not a matter of opinion or trying to give you a hard time...15wt oil in the KLX fork is way, way, way too heavy a viscosity. The compression damping will be way too harsh.

 

I second TNC on this.
If ALL you are trying to accomplish is prevent negative pitching under braking, I can see how the 15w feels like an improvement, but I'd suggest that it might be more pre-load or heavier springs you are actually after.
15w is at the heavy end of the spectrum even for street bikes. Running such a heavy oil off-road puts you at risk for cavitation and possibly even blowing fork seals.