Rotella 15w40 T4 & T6 in Motorcycles

Do you think 30 flows any faster through a pressurized oiling system than a 40 when a PD oil pump (not in pressure relief) is forcing the oil through the system? If so, explain how.
We know oils are graded on flow... not thickness nor weight... so yes a 30 is quicker than a 40...
 
Oils are graded on flow not the notion of separation...
I wasn't really talking about "grade". You do understand that the film thickness separation separation between parts is a direct function of viscosity (ie, "grade") - ?. Do you think all "grades" (viscosity) gives the same oil film thickness between moving parts and the same protection from wear and damage?
 
Do you think all "grades" (viscosity) gives the same oil film thickness between moving parts and the same protection from wear and damage?
Blackstone's 35 years worth of racing and street motorcycle oil
analysis shows no significant differences in WEAR between the grades
or brands... in other words either a 30... 40... or 50 grade oil will meet
and exceed your mileage expectations... what is significant between the
grades is HP and Temps from unnecessary oil drag...

The Importance of Viscosity?
Quote Blackstone Labs

"The viscosity, or thickness of the oil, is not nearly as important
as many people think. Oil retains its nature no matter what thickness
it is.Think about this: automakers are continually recommending
lighter multi-grade oil in new engines. The reason is increased
efficiency. It takes power to pump oil through an engine, and the
lighter the oil, the less power required to pump it. The oil’s ability
to act like a solid and protect parts is not related to its thickness.
If that doesn’t sound quite right, consider this: The gears in a
heavy duty Allison automatic transmission are doing the same work as
the same machine equipped with an Eaton manual transmission. Due to
the hydraulics of the automatic, it runs on a 10W automatic
transmission oil.But the manual transmission uses a very thick
(sometimes up to 90W)gear lube oil. The gears of both types of
transmissions will have a similar life span. We don’t find any
significant differences in wear, regardless of oil thickness."
 
Blackstone's 35 years worth of racing and street motorcycle oil
analysis shows no significant differences in WEAR between the grades
or brands... in other words either a 30... 40... or 50 grade oil will meet
and exceed your mileage expectations... what is significant between the
grades is HP and Temps from unnecessary oil drag...

The Importance of Viscosity?
Quote Blackstone Labs

"The viscosity, or thickness of the oil, is not nearly as important
as many people think. Oil retains its nature no matter what thickness
it is.Think about this: automakers are continually recommending
lighter multi-grade oil in new engines. The reason is increased
efficiency. It takes power to pump oil through an engine, and the
lighter the oil, the less power required to pump it. The oil’s ability
to act like a solid and protect parts is not related to its thickness.
If that doesn’t sound quite right, consider this: The gears in a
heavy duty Allison automatic transmission are doing the same work as
the same machine equipped with an Eaton manual transmission. Due to
the hydraulics of the automatic, it runs on a 10W automatic
transmission oil.But the manual transmission uses a very thick
(sometimes up to 90W)gear lube oil. The gears of both types of
transmissions will have a similar life span. We don’t find any
significant differences in wear, regardless of oil thickness."

^^^ ... ⬇️

Broken Record-2.gif


UOAs don't tell the whole story ... that's been discussed many times in the other forums, which seems that you never really explore. I'll use what the manual specs, never ever will I use a viscosity that is lower than what the manual calls out, and have used thicker oil than what the manual calls out on some vehicles. Because MOFT matters. :)
 
I agree... follow the grades listed in the manual...
Hi, Long time since Ive been here fellas!
So to kind of drag this thread back to topic, Shell T6 is good stuff, great additive pkg & I will try it in both my bike & my 170K mile HHR wagon.
My like-new 2015 XVS950 Bolt-R (purchased 10/21 w/ 89 miles on the clock) is approaching the end of it's 600 mile break-in period. Ive been researching the forums for advice on low cost/bang/buck synthetic oils & cross-refernced filters. Oil filters continue to change as we speak; like recent cut-opens reveal the FRAM Ultra has omitted the wire screen media backing. Not good. Other forums show the only-at-Advance Auto FRAM Titanium may still have wire mesh backed media, but @$15 for the Ti, might as well get a proper K&N, & speculation is Fram will dump it's wire mesh media backing too.
For years Shell T6 has been reported in many biker forums as used in many Japanese bikes, notably hi-mile Jap touring rigs. Also in conjunction w/ cheaper/better constructed high end auto filters and non-bike synthetics, (w/ lots of discord among bike-only purists) there is good evidence for going that route.
Now T6 is almost nonexistent here, but found & bought 2 of 3 jugs of the last 3 T6 5W-40 @ a suburban Oreilly's Auto.
The 950 Bolt owners manual shows an ambient temp oil range chart for the bike w/ 10W-40 in the middle, 20w-50 being the high temp end, & it needs 4.2 qts (4L)
So being the tight wad I am considering 1st oil change.
Lots of bikes run straight 5W-40 T6 as winter oil. However if one was wanting to run 10W-40 (T6 in 10W-40 is not made)
Here's my low cost proposed witches brew to get back to a 10W-40 synthetic;
2qts of 5w-40 T6 + 1qt 10W-40 Super Tech Motorcycle + 1qt 20W-50 Super Tech Moto [5+5+10+20= 40] 40/4 = 10W (?)
Filter: Purolator PBL 14612, & watchful of possible improper tightening interference probs
I'm still shopping/researching filters but have a Purolator Boss

Also wondering if 950 Bolt filter might work on my PC800 both are M20 X 1.5 threads the Bolt is 69mm dia vs 66mm.
will have to try it on for size...

Fellas, please feel free to question my sanity
 
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^ Don't bother with a Frankenbrew / guesstimate hoping to achieve 10w40 viscosity. You'd be better off mixing equal quantities of T4 15w40 and T6 5w40, which will actually produce a 10w40. Or just pay a few extra dollars for a proper 10w40 motorcycle oil. In your shoes, I would run the T6 5w40 straight and be done with it.
 
Almost a year later and I've had the T6 15w40 in both my CB1100 air cooled inline 4 and my VT750 liquid cooled V-Twin.

The verdict? I'm going back to the T4 15w40 on the VT750, but I'm going to try the T5 10w30 in the CB1100.

The T6 was smooth in both bikes and I didn't experience any notchy shifts, but especially on the V Twin, the clutch felt very loose. Sometimes it was hard to find neutral because it would slip so effortlessly from 1 to 2 and 2 to 1.

On several occasions, the transmission would drop down a gear while riding without touching the shifter... It did this on both bikes, but the VT750 was significantly more noticeable.

I suspect that it's because the V-Twin is a much lower revving engine. This "ghost shifting" generally only happened at low revs.

For example, I'm riding along in 5th gear kinda lugging the engine, when I should probably be in 4th... Then it suddenly just drops down a gear, sometimes two...

The CB1100 hasn't been bad, but there were a couple of times when it seemed to drop out of 2nd into neutral more often than it did before with the Honda 10w40.

Also, the 15w40 is a little noisier in the CB1100. Right after I filled it with fresh 15w40, there seemed to be a perceptible valve chatter from the top of the engine.

I didn't bother using a decibel meter but maybe I will measure the noise when I try the T5 10w30, doing a before and after comparing the 15w40 to the 10w30.

The T4 15w40 has worked well in my VT750, and I expect it will again.

The T6 seems to be "too slippery" allowing the clutch plates to slip when their not supposed to.

While I had high hopes for the T6 15w40, in my experience, it's not as consistent as the less expensive T4 15w40.

If the T5 10w30 doesn't work out in the CB1100, I will give the regular 15w40 a try.

I used to use Rotella T 15w40 in a CB750 with good results. The CB1100 engine is very similar to the CB750, but it's quieter...

Either way, I won't be going back to the T6 15w40. The T4 15w40 works better and costs less.
 
I found a Youtube VOA comparison video on the Rotellas, I was going to try using the T5 15w40 Syn Blend in my 2005 Kawasaki Vulcan 800 liquid cooled until I saw the Moly count on the T5 Blend in the comparison vid, the moly count scared me a bit so I'm staying with T4 15w40 conventional, not going to risk clutch slippage. Years ago I did try T6 5w40 on my 2004 Kawasaki Vulcan 1500 liquid but I didn't like the shifting feel using T6 5w40 so drained it after 300km. I'm happier using T4 15w40 in my Yamaha 125cc scooter also, 140cc push lawn mower got the T4 15w40 also. That higher moly count on the T5 15w40 Syn Blend in that video comparison in my opinion is probably why Shell didn't label the T5 jug with JASO MA/MA2 as they did on the T4 15w40 jug.

 
Thanks for sharing the video. There are a good number of oils that have higher moly than T5 15w40 blend. The ones I have used include M1 15w50, M1 20w50 VTwin, Delo 15w40, T6 5w40 (higher moly at the time apparently) and I have used the T5 15w40 as well with no issues. Currently running Redline 20w50 with upwards of 300 ppm moly, and no issues in an 80,000+ mile shared sump ZRX1200 with the original clutch.

Clutch slippage generally is a symptom of something else. Not ruling out moly as a good talking point for potential slippage, however my experience says it is not an issue.

Clutch feel/shift quality is particular to a bike and a riders preference during actual use and is absolutely worth considering.
 
I was going to try using the T5 15w40 Syn Blend in my 2005 Kawasaki Vulcan 800 liquid cooled until I saw the Moly count on the T5 Blend in the comparison vid
Is the Rotella T5 JASO MA/MA2 rated on the oil jug?
 
The diesel oil in my motorcycle inquiry and debate will only end with ICE motorcycles and/or wet clutches.
I did use diesel in my old Sportster.
 
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YMMV, don't be afraid to try different ones out and then dump it for something else. The Rotella does have a cult like following but also at the same time it didn't work out so well for others. I've found that even suggesting the same oil that I use for someone else with the same bike might not even work out either for them.

I've seemed to have good luck since I've been using Valvoline full synthetic 10w40 in my Ninja 650, a lot better than the Castrol Actevo blend I was using which caused notchy shifting and getting hung up in between gears where you couldn't really shift up or down.

Isn't 10w30 mostly a Honda thing now? Most of the bikes I've been interested in all use 10w40.
 
I hate to say this about The T-4 15/40 been using this for yrs in my 4 stroke MX bikes,I purchased new 2023 KX450 SR 2 months back.I have been hitting my local MX track have been getting a spike in my rpms after 15 minutes of doing laps. Right in the meat of the power loamy section of track,have to really pay attention,at first thought it was wheel spin.dumped the Rotella and went with Mobil 1 racing 4T 10/40 not one spike in RPMS with the Mobil. It was definitely slippage with Rotella way more positive rear tire hook up with the Mobil.
 
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