I know that this question is ran into the ground,...and I have done the "oil" search. I just purchased a 01 426 and need to change the oil in it...again. First time I crushed the o-ring gasket on the oil filter cover, not good. I put Amsoil 10W40 in that time. Ran the bike about 5 minutes with the Amsoil. Most of it leaked out. Need to change the oil again! I understand that Yamaha doesn't recommend synthetic oil, my local MX Accessory shop didn't know what I should use, Thumper Racing doesn't recommend Mobil 1, a lot of you guys recommend Mobil 1! Thumper Racing uses Maxima 20W50. What do I use. This is becoming a pain in the @#$!




You cant go wrong with Yamalube. Thats what the manufacture recommends. Ive been using Mobil 15-50 since December in my 01 426 without a problem. I changed over to Mobil 1 because my dealer was out of yamalube. I havent had any problems so I didnt switch back. If you have doubts, just use Yamalube.


This oil subject is absolutely ridiculous! Why do people need to experiment with any thing other than what works. Your manuel tells you and all of us what is recommended, why? Yes,to sell some oil, and because it works.

This is what kills me: YZF400/426 oil needs to be changed after each race or every 2nd or 3rd ride. If owners do not follow this basic YZF rule, they are opening themselves up for motor/tranny/clutch issues.

I do not want to experiment with different oils in my 4stroke, as I did not experiment with different oils in my 2stroke.

With Yamalube you have 2 choices: the cheaper

Yamalube 4 or the more expensive Yamalube 4R.

I do not get the excuse that $ is the issue here.

And the clutch slipping issues are from people that do not know how to properly ride 4strokes.(this will get some response)

I have used both since the YZF400 came out in 1998. I use 4R in my 2001 YZF & WR426, why? It works........no motor, clutch,tranny issues in the 6 4strokes that I have had the pleasure of owning. If you change the "life Blood" of your bike correctly oil brands are a personal issue only. I choose to use what works for me & the Factory Race Team.

Thanks GA426OWNER. After spending $5,800 on the bike, I'm not that worried about the cost of oil! I am going to run the YamalubeR....picking up a case today! Are you going to the race at Paradise this weekend, if so let try to meet. Not sure who you are.

Brian Williams


No fancy advertising or packaging here. I've raced my bike every weekend for a year now and use the cheap 20-50 and change it weekly and it hasn't missed a beat.


Hey Brian, No I won't be at Paradise this weekend, got family issues. But, I wish I was going. I love that 60mph uphill jump! Have you qualified for Loretta Lynns? Or are you fun racing/practice at this point? Where do you ride most?

The only reason I run Mobile 1 over yamajube is cause I don't have to drive 24 minles one way to get it. Mobile 1 has worked fine for me and saved me a ton of time not driving to buy it. Granted I could buy it by the case but my dealer has to order that cause they suck and won't sell a full case of there stock. I can easily pick up the Mobile 1 on the way home from work. I agree about the clutch slipage probably being due to the rider. If I abuse mine hard on the track it gets hat and slips.



When in doubt, GAS IT!

What are you, YELLOW?

If it's dirty, I do it and think it!!

Did qualify for LL, not going to go to the Regional at HillBilly Hills though. Racing the GPG series (for fun..I have found the Fountain of Youth..it motocross!)..Jr Vet Nov and 250C. Concentrate on the Jr. Vet Novice class. Think I am running 4th in pts. Love that Step up at Paradise! Will be the first time on the 426. Can't wait..this bike rips...my YZ250 was mod'd to the max..Tom Morgan engine and the 426 is still faster and easier to ride! Practice at the X Track, Lanier MX, or on race weekends. All these adult responsiblities get in the way of my FUN! Hope to meet you some time.



I have worked and a couple of shops and have heard all the stories about oil .I will say this car oil is for cars .It is blended different and it doesn't have the additives for the abuse of the clutch.I have seen the results on some engines .I f you do use car oil you must change it after EVERY ride .I run your standard honda gn4 or for those of you who like syn,golden spectro is great it is the best of both worlds a syn with a petrolum base

I run Mobil 1 TriSynthetic 15-50 in my 250F and my 400F before that - no problems.

Does anyone have any idea why Yamaha recommends you change the oil in your bike so often? The 400 doesn't really rev all that high, at least by the standards of street bikes, which have many more cam lobes, bearings, gears and horsepower for the oil to deal with. Granted there is much more oil in the street bike, but why can I go 3000 miles on my Gixxer (running Torco petro/syn blend 10w-50), but my manual wants me to run no more that about 50 miles on my Thumper? Anyone? Anyone? Buehler?


The 400 revs pretty high for a 4-stroke. Also the environment in which it operates, dust, sand, water, and your clutch requires more frequent oil changes. It may not rev as high as a street bike, it is still a high performance 4-stroke

[This message has been edited by mike68 (edited 06-13-2001).]

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now