To counter your point for future reference for other KDX owners, I 100% disagree about Lucas being the problem. Why? Lucas doesn't produce crap products to start with. All of their other products have a great reputation so why hurt that reputation by making a crap product? It makes no sense that they would produce a 2T oil that harms 2T bikes as that would be a piss poor business decision.
Second, I've been running it for years now after switching from 927. I run my 220 hard to keep up with the bigger bikes in sand washes and such. I'm at 150 maim, 38pj, CEK needle @ 2000ft. To date I have had zero issues and everything looks as it should. Another example, my buddy has run nothing but Lucas in his 2018 YZ250X since new and I, literally, just did the first top end on the bike this week. Guess what I found? Other than some blow by due to being way overdue for a top end, the cylinder looked absolutely mint. The piston had no scoring or scuff marks and no sticking rings. This is with over 300 hours on a stock cast piston!
![Shocked :shock:](./images/smilies/icon_eek.gif)
(he's a cheap bastard
![naughty :naughty:](./images/smilies/eusa_naughty.gif)
) There was plenty of oil on the cylinder and the piston itself. This was running the bike pretty lean with a 168 main, 45pj, 40 power jet, and Suzuki tri-taper needle running 40:1 with Lucas and 91 pump ethanol fuel @ 2000ft. For both of us, this is riding and racing in the Arizona desert, with lots of super hot days, wide open sand washes and hill climbs.
Third, I do have a theory as to why Lucas might show up in more "failures" than other oils... I think it is largely due to it being available at most auto parts stores (unlike 927, Motul, etc.) where the uninitiated noobs that don't don't know squat about jetting, bike setup, or working on 2T bikes in general, can easily use it. I would bet, if most of the people that had failures were truly able to diagnose the real issue, it was something else (forgetting to actually add oil to fuel, guesstimate oil ratios, jetting way too lean, cheap/knock-off pistons, improper ring gap, cheap/knock-off bearings, air leaks, etc.) that caused the issue(s) but the oil is easy to blame. Not saying these people didn't have an issue but it's physically impossible to add the proper amount of oil to your fuel and the cylinder to be completely dry unless you weren't getting fuel at all.
That all said, use what you like and what you feel protects your bike. After tearing down top ends that have been using Lucas for hundreds of hours without issue, I feel completely safe running it in my bikes and will continue to do so.