I don't see a major company such as Shell which makes Rotella messing around and not knowing their oil meets spec even though it is a claim. I think that's been debunked many times although it becomes fodder for discussion around here almost once a week or more.
Whats the least expensive JASO MA spec full synthetic?
- Thread starter grampi
- Start date
Yeah, any big name oil company can probably be trusted. Even the Valvoline conventional and full synthetic motorcycle oils don't have the JASO registration logo on the bottle (see below), nor are they on the latest JASO registration list (I just looked at the Sep 2025 list PDF download). There are 5 Valvoline oils listed, but none are for the Valvoline motorcycle oil I've ever used.
But here's the clincher. Castrol "Power 1" 10W-40 which I've used before is on the JASO registration list, but it doesn't have the JASO registration logo on the bottle. If you read all the JASO documentation it doesn't really say that the registration logo HAS to be put on the bottle. This is on the Sep 2025 JASO list. So, this proves it can be registered with JASO, but not have the JASO logo on the bottle. Adds more confusion, lol. Side note - SuperTech motorcycle oil is not on the list. The only Shell oils on the list are also shown below.
It gives guys like us something to throw around on the forum. I got a gen 1 Vmax running for a friend about this time last fall, hadn't run in years. He's run yellow bottle 10w40 Pennzoil in it its whole life. Once it was up and running, it ran as good as any bike could. As in aside, the reason that bike did the quarter mile so fast, it turns 4000 RPM at 60 main top gear. It was geared so short.
That, and Jay 'Pee Wee' Gleason was small in stature and light in weight, and also VERY skilled.
My best bud had a Vmax when I had an FJ1200. He did often comment/complain about the high RPM rolling down the highway, and it's limited tank range. In contrast my FJ had a bigger gas tank, while also getting better MPG.
My 1980 XS1100 Special turned the same 4,000 RPM at 60 MPH in top gear. I put the final drive gear/housing from an XS750/850 on it and lowered it to 3600 RPM at 60 miles per hour. That was a very popular modification for the XS1100. I suspect the VMAX would overpower the XS750/850 final drive housing/gears, however I've always wondered if the VMax wasn't the same final drive housing as the XS1100 used. I don't see the XS750/850 FD swap mentioned as a modification for the Gen1 VMax. Maybe they weren't compatible but in any case, Yamaha stacked the deck in their favor for sure.
I noticed even M1 doesn't have the JASO registration logo. It just says it meets the standard. I wonder if that logo/registration has been reserved for only the oils branded by the motorcycle companies? Of course those oils have greatly inflated prices...
Yeah, I had a first gen Max, and that was one of my complaints about the bike. It desperately needed a 6th gear. An engine that made that much power and torque didn't need to be turning 4K at 60 MPH...
Per the JASO documentation, it sounds like anyone who meets the requirements that are submitted and vetted through JASO can put the registration logo on the bottle if they want to. I searched the Sep 2025 JASO registration list (link given earlier) just now, and only saw these two Mobil oils, but they look to be a variety not sold in this country.
I have noticed that oil sold through Honda, Yamaha, Kawasaki and Suzuki will have the JASO registration logo on the bottle. My example of the Castrol Power 1 given earlier in this thread shows it can be in the JASO registration list, but won't have the registration on the bottle.
This JASO thing is far more subjective than it should be. It SHOULD be far more cut and dried, like it either does, or doesn't meet JASO MA specs...certified!
It will either say it "meets or exceeds" MA or MA1 or MA2 on the bottle (like the Valvoline in post 142), or it won't. Or it will will have the JASO registration logo on the bottle (like the Yamalube in post 139). It's not really a direct "certification" by JASO because they don't do any actual testing ... that's up to the company submitting the information to JASO for review to determine if it passes or not. For the friction testing, I'd suspect that the submitter hires a certified test lab to run a test like that, but JASO isn't directly involved with that. JASO probably won't take test data from an uncertified test lab, or test data done "in house" that's not certified.
If it doesn't have the JASO registration logo and just says that it "meets or exceeds", or it's not in the JASO registration list, then that means JASO hasn't been supplied with all the required info to determine if it really does meet the requirements to be registered with JASO. That's when you just have to trust the oil seller that it really would pass all the JASO requirements.
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I've been using Shell Rotella T4 15W40 (yes, not a synth) in my 77 CB550 and 79 CM400A for years with no issues. Just recently switched to T6 15W40 which is about the same prices as a gallon of GN4 10W40. With rebates on the 2.5 gallons of T6 from TSC it ends up costing about the same per gallon as T4. Great deal and great oil for the price. I change mine about every ~1000-1500 miles. Got 40,000 on the CM400A and rebuilt it last year "just because" but it was unnecessary.
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