5W-40 Rotella T6 causing clutch slippage?

[metroplex]

I switched to Rotella T6 in my 696 over the winter and was able to ride it today. I noticed that during high RPM upshifts, the clutch will slip big time causing the RPM to spike up momentarily.

I used T6 because it seems to have favorable reviews among other wet clutch motorcycle riders, including Ducati riders. Has anyone else experienced this? Do I need to go to M1 V-Twin 20W-50 synthetic or Motul/Silkolene xW-50? The T6 meets JASO MA, so I'm not sure why the clutch would do that during an upshift. Downshifts seem fine, as is WOT at high RPM in gear.

[elgallo73]

I used Rotella T6 in my 696 (2011) last fall but did not notice any clutch slippage.  Not sure what is going on in your situation, but it is possible that the lighter weight coupled with being synthetic could be causing some slippage.  I'm not critiquing your riding style (you should see my chicken strips...) but it could be technique as well.  From my reading, it seems that many slippage issues are a result of technique and have nothing to do with the oil.

If it helps, I switched to Rotella T 15w-40 and could not be happier, used it during our heat wave last summer (North Texas) and no issues.  Just finished a valve lash check and the heads were clean.  Change it every 2,000 miles.

If you want to stay with synthetic, Mobile 1 15w-50 is an excellent choice as well.  You'll get a million opinions on oil, but if you stick with a reputable brand in the proper weight range (even automotive), I don't think you can go wrong...

[metroplex]

Thanks, I think you're right about technique. I'll keep an eye on it, because it didn't make sense for the oil to cause slippage only during upshifts.

[stopintime]

It's during upshifts that the clutch is hit by max torque, so that will be where slipping occurs.

Bike mileage?

IMO 5-40 oil is too light, at least for a wet clutch. Try 20-50, maybe even semi synthetic....

[zarn02]

Synthetic isn't going to be the problem. Your bike comes from the factory with synthetic. If the oil is indeed the culprit, I would be more inclined to suspect it's due to your wet clutch not liking an additive in that particular oil. Perhaps try a moto-specific oil.

Also, the oil thread is a good read:  http://www.ducatimonsterforum.org/index.php?topic=1912.0

(I know my name's on the posts, but I didn't write it, only transcribed and edited.)

[elgallo73]

Synthetic isn't going to be the problem. Your bike comes from the factory with synthetic.

Spot on, sometimes my mind is doing too many things at once.  I'm still on the fence regarding additives affecting clutch operation, specifically moly.  To date, I have yet to find any serious empirical evidence showing this to be a problem and if someone here can attest to this being an issue, I'd love to know about.

We used automotive oils in motocross bikes for some time (10w-30 typical) with the much discussed moly without issue, and this was with some SERIOUS clutch abuse.

Seems to me the vast majority of clutch issues are more likely worn springs and/or technique, more likely the latter...

[ducatiz]

Synthetic isn't going to be the problem. Your bike comes from the factory with synthetic. If the oil is indeed the culprit, I would be more inclined to suspect it's due to your wet clutch not liking an additive in that particular oil. Perhaps try a moto-specific oil.

Rotella T6 (5w40) is JASO-MA.  So is Shell Rotella T 15W-40 (only the former is full synth)

I have used Mobil1 "High Mileage" with zero problems.  The High Mileage version does not have friction modifiers and tastes the same as the Mobil1 10w40 MX4T

[Curmudgeon]

I have used Mobil1 "High Mileage" with zero problems.  The High Mileage version does not have friction modifiers and tastes the same as the Mobil1 10w40 MX4T

You are drinking the stuff now?!  Where did you get the info on the friction modifiers? Which "High Mileage" are you using?

Son just changed the oil in his ST4s today with 15W50 which is the same stuff I'd use in my V8's if I weren't using BG because the 15W50 has 1300 ppm ZDDP. With a dry clutch this is a no brainer, but with a wet clutch...

Mobil 1 stopped making Racing 4T 15W50 which they made for Triumph. I used my last gallon for the last change on my Bonneville and was looking for what to use next as I wouldn't put the now recommended Castrol in a lawn mower.  Mobil 1 says to use 20W50 V-Twin but I'm not convinced it has the same shock protection the 4T had. http://www.mobiloil.com/usa-english/motoroil/car_care/askmobil/Oil_for_Triumph_Bonneville.aspx

Of course Donnie uses 15W50 Redline which he buys by the drum because it never let him down in all his years of racing. No wet clutch problems with it according to Donnie either. I realize it's an ester-based and a different full synthetic animal. http://www.redlineoil.com/product.aspx?pid=6&pcid=21

[ducatiz]

You are drinking the stuff now?!  Where did you get the info on the friction modifiers? Which "High Mileage" are you using?

i am a sommelier of fine oils

this one:  http://www.mobiloil.com/usa-english/motoroil/oils/mobil_1_high_mileage_10w-40.aspx

The ONLY thing I've noticed is that the clutch in my S2R is actually more "Grabby"..

I've considered sending it out for analysis, but so far so good. 

I saw it referred to on several bike forums and gave it a try. 

Mobil 1 stopped making Racing 4T 15W50 which they made for Triumph. I used my last gallon for the last change on my Bonneville and was looking for what to use next as I wouldn't put the now recommended Castrol in a lawn mower.  Mobil 1 says to use 20W50 V-Twin but I'm not convinced it has the same shock protection the 4T had. http://www.mobiloil.com/usa-english/motoroil/car_care/askmobil/Oil_for_Triumph_Bonneville.aspx

Have you ever thought about mixing the M1 10w40 and the 20w50?  You'd end up with a 15w45 if you mix it 1:1.. yes, i know it doesn't EXACTLY work like that, but it can't hurt to try. they are both JASO/4T (wait is the 20w50 4t too?)

[Curmudgeon]

Have you ever thought about mixing the M1 10w40 and the 20w50?  You'd end up with a 15w45 if you mix it 1:1.. yes, i know it doesn't EXACTLY work like that, but it can't hurt to try. they are both JASO/4T (wait is the 20w50 4t too?)

Hmmm... If 4T is just = motorcycle oil, then V-twin must be 4T as well. The Mobil 1 blurb on V-Twin states that it's more stable at high temps "because the rear cylinder of a v-twin usually runs hotter than the front at low speeds". That's logical enough. The T-100 is rarely revved past 6,000 and rarely sits in traffic for extended periods, so I might just try the V-Twin or possibly mix 1:3. Would be less inclined to try this on a 9,000 RPM Ducati of course.

Your 800 have the same ATPC clutch as my 796?

[metroplex]

I'm apprehensive about trying non-JASO MA spec oils in my ATPC wet clutch in the 696, even though a VOA might show a low moly content. I've heard mixed results using M1 V-Twin 20W-50 in the Ducs.

[ducatiz]

Hmmm... If 4T is just = motorcycle oil, then V-twin must be 4T as well. The Mobil 1 blurb on V-Twin states that it's more stable at high temps "because the rear cylinder of a v-twin usually runs hotter than the front at low speeds". That's logical enough. The T-100 is rarely revved past 6,000 and rarely sits in traffic for extended periods, so I might just try the V-Twin or possibly mix 1:3. Would be less inclined to try this on a 9,000 RPM Ducati of course.

Your 800 have the same ATPC clutch as my 796?

that's the one.  I've contemplated swapping it with a regular one from an 800SS.

[ducatiz]

I'm apprehensive about trying non-JASO MA spec oils in my ATPC wet clutch in the 696, even though a VOA might show a low moly content. I've heard mixed results using M1 V-Twin 20W-50 in the Ducs.

you can try it and then drain it if you no likey

[metroplex]

At first I thought it was my technique, my clown feet size 12 boots are a PITA to fit into that shifter area and my first time out after the winter might be rusty. But I looked at my datalogs from last summer and I usually dropped the throttle to about 11% or less after I clicked the upshift and the RPMs wouldn't spike.

I looked closely at yesterday's datalog and it shows the RPMs spiking as I dropped the throttle. This is something new, and the difference is I'm using Rotella T6 instead of whatever the dealer/factory used.

I've attached snapshots of 3 areas where the RPM spikes occured. I had to zoom in otherwise it looks like I'm pegging the throttle open during the upshifts. If it is indeed my technique, it feels like the previous oil would allow the clutch to grip better after an upshift.

[Curmudgeon]

that's the one.  I've contemplated swapping it with a regular one from an 800SS.

No temptation here as mine appears to work as advertised. Never had a hint of chirp from the rear wheel on rapid downshifts. Admittedly, I match revs for the most part and have always preferred the engine to the brakes.  What are brakes?! 

BTW, I had a few incidents of howl (light load, in traffic, hot engine) from the clutch on the factory fill which disappeared after Donnie refilled mine with the Redline 15W50. Go figure...