An oil thread - progress report on 5W-40 synth

[Grimly]

Some you who actually give a rat's ass, will recall I posted about moving to fully synthetic oil for the past winter to avoid clutch grab. Never one to spend a Euro where a 50c will do, I tempered this rash indulgence by choosing Lidl's offering of 5W-40, at €5/L and gaily sploshing some of that in the crankcase. Some Champion Racing 5W-50 was added for a dash of extra zddp.
The results exceeded my expectations - there was a lack of cold-weather clutch grab, but there was also an immediate feeling of the engine being free-er to rev and the butt dyno certainly noticed an extra oomph.
So, winter passed, and things carried on, but suddenly, almost like flicking a switch, at the 1000mls mark the gearchange started to feel a little rough - any one of you will know what this means. It means the oil has lost condition and if the sliding parts of the gearbox are transmitting a slight roughness to the boot, it possibly means other parts of the engine aren't getting the protection they need.
So, erring on the side of caution I dumped out the 5W-40 and refilled yesterday with Total Racing 10W-50 fully synth for the summer and will continue. Mileage permitting, I'll contine to run the 10W-50 until next winter and the top-up oil will be 5W-40 from late autumn.
I'm slightly disappointed in the 5W-40 not being as long-lived as I'd hoped, but the lack of clutch drag made it a worthwhile spend of time and money to at least find out if it would work or not.

To those who say, "Use Rotella T6" - that's not available here, and the Rimula equivalent isn't available across the counter.

[Brendan W]

I too have been dabbling with the Lidl W5 stuff. Used a 10w40 semi last summer with no complaints. Is it true that wider viscosity ranges mean more VIs have been added and it goes off quicker? Right now I'm dabbling with a 15W40 semi with no issues.
Next change the plan is to use Maxol tractor oil if I can get 5litres to try out.

[Steve]

It it my (unproven) theory that mixing the oils might be part of your problem. You can't guarantee that the different additive packages are playing well with each other, and don't know which one "went south".

Yes, Rotella is popular here, but more-importantly, it's the fact that it's a diesel truck oil. Not sure what your emission laws are over there, but here, they have been slowly reducing the levels of some important "heavy metals", like zinc and phosphorous, in motor oils because, as cars age, the worn-out engines will burn more oil, sending those metals to the catalytic convertors, plugging them up. So far, the oils designed for diesel trucks still have higher levels of zinc and phosphorous, and they are what do some of the heavy-duty protection in the transmissions of our bikes.

.

[mrbill5491]

Don't forget, the gears in the transmission tend to shear oil molecules, tearing it apart over time. That could be part of the problem you saw when your oil went south.

[Grimly]

I too have been dabbling with the Lidl W5 stuff. Used a 10w40 semi last summer with no complaints. Is it true that wider viscosity ranges mean more VIs have been added and it goes off quicker? Right now I'm dabbling with a 15W40 semi with no issues.
Next change the plan is to use Maxol tractor oil if I can get 5litres to try out.

Synthetics inherently have a much wider viscosity range from the beginning, but the black art and trade secrets jealously guarded mean the likes of ordinary mortals don't get to know exactly what's in the bottle from maker to maker. The Lidl (Pennasol) oil is probably half-decent to start with, but Pennasol might have blended a grocery oil specifically for them and it might or might not be the same as the 5W-40 that's on the Pennasol site. I'd not be surprised to find that Lidl shift as much motor oil as any of the large car shops, so worthwhile business for a refiner/blender.

It it my (unproven) theory that mixing the oils might be part of your problem. You can't guarantee that the different additive packages are playing well with each other, and don't know which one "went south".

Oh yes, it's a bit of a guessing game, but the chances are that it's nothing more than simple wear and tear of the oil, as happens with many of them. That, and the last 1000miles have not been 'easy' on the oil, as I've been ragging it around a fair bit. I'd not be surprised if the 10W-50 lasts much longer to shear-off point.
I could have carried on using it, but this is the thinnest oil I've ever ran in it and even though the spec sheets all say the film strength is excellent, blah, blah, blah - it's all so much BS if it simply starts to feel worn out. Perhaps it isn't, perhaps there's another 1000 or 2000 miles left in it, but I thought to cut my risk.

Yes, Rotella is popular here, but more-importantly, it's the fact that it's a diesel truck oil. Not sure what your emission laws are over there, but here, they have been slowly reducing the levels of some important "heavy metals", like zinc and phosphorous, in motor oils because, as cars age, the worn-out engines will burn more oil, sending those metals to the catalytic convertors, plugging them up. So far, the oils designed for diesel trucks still have higher levels of zinc and phosphorous, and they are what do some of the heavy-duty protection in the transmissions of our bikes.

Thinking seriously of just a simple synthetic 10W-40 diesel oil, but that genie of the 5W no-drag clutch keeps popping up.
There's no shortage of other makes of synth DEOs here - if I find a good one at the right price, I don't mind changing it more frequently.

Don't forget, the gears in the transmission tend to shear oil molecules, tearing it apart over time. That could be part of the problem you saw when your oil went south.

Oh, I'm fairly sure that's it. The change was sudden, and in half the time it usually takes for a 15W-40 to shear out. I'd even run 20W-50 a few times when it was doing long sustained high-speed runs every day of the week, with no downside, and even that sheared out at 2000 miles almost bang on the mark.

[madmikeracing]

Geesh Im almost scared to say anything about oils ha ha. I do know Guys who have used Synthetics exclusively in Engines that sit quite a bit, have upon dissassembly of engine noticed more rust than usual inside the engine , Like cam lobes that are not immersed in oil are a bit rusty where before with Dino oils this had never occured. Guys synthetic just doesnt stay on the parts as well when sitting for long periods of time . This is what I have read , Just thought it interesting Fact, Also wonder if gears and shafts hold up better during extreme shock loadings? I imagine once again Dino Oils would maybe be better ? Maybe it really doesnt even matter >??? !! Thanx Mike

[Grimly]

Yeah; even though the film strength is higher, maybe it doesn't stick around as long - something to keep an eye on, good point.
Otoh, I'm utterly sure the synths cope with higher stresses when in ordinary use, so if the lump isn't sitting for months unused, there won't be a problem. Everything is a compromise in one way or another.

[Grimly]

Errata: When I looked at the change record I discovered the oil had lasted 1700 miles before it went off, not 1000 as I thought.