I am willing to listen, seriously, I am.
Could Rotella T6 be too good? Possibly.
Maybe BRP should specify a designated rating that clarifies the owners manual. As is, they stipulate a motorcycle oil and a rating that is reflecting a minimum or higher.
As mentioned, maybe it is too good. Should it meet JASO MA2, not according to BRP.
http://en.wikipedia.org/wiki/Shell_Rotella_T
Motorcycle usage
Though marketed as an engine oil for diesel trucks, Rotella oil has found popularity with motorcyclists as well. The lack of "friction modifiers" in Rotella means they do not interfere with wet clutch operations. (This is called a "shared sump" design, which is unlike automobiles which maintain separate oil reservoirs - one for the engine and one for the transmission). Used oil analysis (UOA) reports on BobIsTheOilGuy.com have shown wear metals levels comparable to oils marketed as motorcycle-specific.
JASO-MA
JASO is an acronym that stands for "The Japanese Automotive Standards Organization." Among other things, they set standards for oil to be used in motorcycles.
Shell Rotella T 15W-40 conventional oil does list on its packaging JASO MA as one of the specifications it meets. Note that the 10W-30 conventional oil does not list JASO-MA.
The newer fully synthetic T6 5W-40 oil lists JASO-MA compliance on its packaging and on the Rotella website.
I said I am willing to listen, the internet has many posts about T6 being used in machines will mileage on them and some have had clutch slippage. There is also a large following of people using T6 with no issues.
An auto clutch can be a difficult item. When we raced Karts, wet clutches were common. While not the exact same, these were smaller in size, but similar in effect. The settings were adjusted to create slip to a given point of torque.
This is a copy and paste from the 2013 RT owners manual
EngineOil
Recommended Engine Oil
The same oil is used for the engine,
gearbox, clutch, and the Hydraulic Control
Module (HCM) on the SE5 model.
Use the XPS 4-STROKE SYNTH.
BLEND OIL (SUMMER) (P/N 293 600
121) or a 5W40 semi-synthetic (minimum)
or synthetic motorcycle oil
meeting the requirements for API service
SL, SJ, SH or SG classification.
Always check the API service label on
the oil container.
NOTICE To avoid damaging the
clutch, do not use a motor oil meeting
theAPI serviceSMor ILSACGF-4
classification. Clutch slippage will
occur.
NOTICE Do not add any oil additives
to the recommended oil. This
may lead to gearbox and clutchmalfunctions.
This is a copy and paste from the current Shell information spec sheet.
SAE Viscosity Grade: 5W-40
API CJ-4, CI-4 PLUS, CI-4, CH-4, SM, SL, SH; ACEA E9; Caterpillar
ECF-3, ECF-2; Cummins CES 20081; DDC 93K218; Ford WSS
M2C171-E; JASO DH-2, MA; Mack EO-O Premium Plus; MB Approval
228.31; Volvo VDS-4
According to current published info, the T6 should not be used in the 2013 Spyder.
Possibly Shell had not submitted the oil for new testing when you ran it. Maybe it is just too good for a motorcycle wet clutch, but it seems odd it meets the specs for a wet clutch.
Really, I am listening. Explain some more beyond the clutch slipped and stopped slipping after the oil was "flushed" out. By the sound of it, T6 is too good and an oil that can hold the clutch is less of an oil.
FWIW, I did some looking at BITOG older posts from 2010 and back then T6 was rated as an SM. Not sure what to say, could there have been some bad info and you used an SM oil in a machine specifically not approved for it. I don't know and not accussing, simply asking. Again I am willing to listen.
PK