I've read different posts on other forums claiming that rotella T4 has changed it's formula and isn't as good as it used to be as far as wet clutch comparability? I race mx with a built trx450r and I am not easy on the clutch. Ive been using it in both cases. Is Rotella still a good option or are there any better brands out there?

It's just as good as it has always been. I assume you are interested in the 15W40 version?

Does it still (did it ever?) have appropriate JASO specs?

I am not sure if it ever met the specs for JASO, but I pretty sure it never carried the JASO certs. Those 450's are fun, the power delivery reminds me of a two stroke.

I believe at one time it was jaso-ma certified but according to the website, it is now only jaso-dh2 which I believe is a certification for Japan diesel engines. I believe rekluse clutch company is shying people away from it because of problems they've been having with the new t4 formula.

Rotella T4 meets JASO DH-2, MA, MA2. Call it up on Rotella.shell.com. Also, Rotella T4 is a large improvement over Rotella T. Check their website.

JASO is the Japanese Automotive Stanards Association. JASO MA and MA2 is a standard for four cycle motorcycle engines. Re-check the website at Rotella-Shell.com. It meets the MA,MA2 specs. JASO DH2 deals with diesel oil specs. If you are dealing with wet-clutch systems the 4T spec oil is a good choice.

Why run diesel oil in a wet clutch system when you can run this?

I dont think Rotella ever submitted to JASO but were confindent enough to say it met the standards.

Here is the current list of JASO oils http://www.jalos.or.jp/onfile/pdf/4T_EV_LIST.pdf

FWIW just about any 15w40 has stout enough add packs and lack of friction modifiers for a happy wet clutch.

I just checked the Shell website. There was no longer a certification for JASO-MA. It only mentions JASO-DH2 which does not relate to motorcycles.

Rotella.shell.com

You’re are not looking hard enough. Go to Shell.rotella.com. The go to Shell Rotella Products. Then Shell Rotella T4 Triple protection.
Then hit Download the Shell Rotella T4 Triple Protection Brochure. Then curse to the lower left hand corner in a yellow box.

Read JASO DH-2, MA,/MA2 and about 17 other specs.

That was my belief as well, I thought it was just implied that it met the specs.

My Suzuki S40 needs ZDDP along with a JASO MA.
Rotella T4 fills the bill well and is cheap as dirt.