According to MrDuhFactor on
He says do not use fully synthetic oil on the KLX250 as the clutch will slip.

Well, i just did an oil change a couple of weeks ago, and for the first time in its life 6k 2009 KLX250sf, i went ahead (before seeing this video) and put synthetic oil in it.. Valvoline 10w40 to be precise.

I'm also about to buy a pumper carb and 351 kit from Bill Blue. The bike has probably only done 100miles max on the synthetic oil. Should i drain it out, asap and put regular 10w 40 in ?

I'm in SW Florida, (if that matters) and its hot all yr round.

 

I just did 351 and Pumper, used Dino for the break in, but normally always use semi syn. Motul 5100 I think it is. Never heard of it being bad, and my clutch has never slipped.

 

BTW you're gonna LOVE the new setup

 

I always used Full Synthetic in all my bikes, never slipped a clutch.

 

+1 Never a issue. I do buy motorcycle full synthetic that is made for wet clutch engines.

 

I use it on engines I care about like my KLX. Clutch may slip only if it's just about to anyway. Just make sure you use oil (any oil) that's for wet clutch motorcycles.

 

At 1:45 of MrDuhfactors video, he seems pretty adamant not to use synthetic oil. He is a very competent mechanic. Built a KLX from the ground up pretty much in his series of videos.

This is what has me concerned.

 

I've used Mobil 1 full synthetic since it first came out many years...decades ago...my first 1973 Kawi Z1900. I can't even count how many road and off road racing bikes I've used the stuff in. All the 4-strokes had wet clutch systems shared with the engine. Amazingly I never burned up the clutch in any of them, and frankly I'm shocked that none of my enduro competition bikes killed their original clutches...usually 2 year spans for the racing models. I think the synthetic oil death on clutches deal is way over stated. I'm sure there must be some exotic syn oil out there somewhere that might have an additive that would be hard on a clutch, but most any quality syn oil you can buy off the shelf from a big box store will be fine.

 

The syn oil labeled as energy conserving have additives that will make your clutch slip. As long as you don't use them, you will be fine

 

Mobil 1 with the Gold cap (use to be Red) is all I use.