Syn Oil Options for a Triumph Air Cooled Thruxton

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I have an air-cooled 2013 Thruxton with about 20K miles. Old technology, but with EFI. Inadvertently started an impassioned debate on appropriate oil at the Triumph Rat forum. The bike has a wet clutch and the manual recommends 10W/40 or 15W/50. Manual also specs API SH (or higher) AND JASO MA.

Have been using Mobil 1 15W/50 @ 4K oil change intervals up to now and seemed fine. I do not ride in temps much below 45degrees, mostly 60/70/80+. Of late have been noticing gear changes getting increasingly clunky after about half an hour of riding in hotter weather. No clutch slipping! Of more concern is the trans seems to react to bumps in the road. Almost feels like it is going to implode, or the back half of my bike is going to fall off. This feeling is through my seat and only happens when riding over bumps. The ride immediately returns to normal after the bump. Very disconcerting.

With the focus on oil on this forum, thought I would reach out to the collective membership's expertise/experience for opinion. Some forum members are blaming incorrect oil selection. The oil I have been using is NOT JASO MA but many have attested to it working fine for their bikes. I am not particularly knowledgeable on all the spec abbreviations/standards and their implications! Link to M1 product info herewith..... M1 15W-50

Thanks in advance for any advice.
 
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Very cool looking bike! While I never pulled the trigger, it has been on my short list several times.

I would have suggested the oil you are already using...so no further advice there. M1 15w-50

You description of the transmission over bumps would be worrying, and likely not oil related IMHO. Have you checked chain tension (too tight or too loose)? Is your rear axle properly tightened? Shocks top and bottom tight? Transmission spur gear tight? Play in shock pistons?

I am guessing if the feeling is as you describe, you have something mechanical as your culprit...not your oil.
 
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Why not just try a JASO MA rated oil like Amsoil 10W40 or 20W50 to see if it makes a difference. Mobil 1 also makes motorcycle specific oils in 10w40 and 20W50 as well. The price isn't goin to be much different.

The trans over bump thing sounds like a loose axel or maybe swing arm? Get it on a stand/lift and check it out.
 
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I recently got a 2016 Kawasaki voyager, and the manual says to use oil rated Jaso 2 and Api Sl. Its because there safe to use without causing clutch slippage. But I would bet, you could use any oil that just has the SL rating. Vavoline states on their bottles of 10/40 and 20/50 wt motorcycle oils, both of the rating I posted. That's what I have been using without any issues.,,
 
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Of late have been noticing gear changes getting increasingly clunky after about half an hour of riding in hotter weather.

Manufactures warn owners that our gears can't shift smoothly if our clutch is part
way engaged... check for unwanted clutch drag after riding in the hot weather...

Here are the steps how to check and eliminate unwanted clutch drag...

1 Place your bike on the center stand...

2 Start engine and establish a steady idle at 212ºF (operating temp)...

3 Squeeze in the clutch lever and shift into first gear...

4 Continue holding in the clutch lever and note if the rear wheel coast to stop or not...
if it continues spinning that's unwanted drag... adjust...


To adjust a cable equipped bike turn the small knob clock wise (out)
1/4 turn and test for clutch drag... if your bike is equipped with
hydraulics bleed system for bubbles...


Ultimately you want the rear wheel to coast to a stop when the engine
is idling and first gear selected with the clutch lever is squeezed in...


A tip on shift TECHNIQUE...

I think we are after the same thing... smooth shift without upsetting
the suspension... the secret is moving the foot quicker than clutch or
throttle... go easy with the clutch and throttle but move your foot
quick... but worry there is no such thing as too quick... its early
form of seem less shifting...
 

CleanSump

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I'd recommend using what Triumph spec'd and see if it helps.
To be blunt, you aren't doing what the manufacturer recommends and then complaining about the result.
 
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The oil very much more than likely is not his problem in this. It wouldn't take 20,000 miles for a problem show up. It's something with the transmission, which wear and tear on that with M1 15w50 is no more or less than any other oil.

I like the idea of checking chain tension and BLS has a good idea for you in checking clutch adjustment.

Like I said what you were describing is not a oil related, it's something mechanical. For grins drain that oil (save it in a clean container, no sense wasting it if you're nowhere near an oci) and put in 15w40 T4. Betting dollars to donuts it does the same thing. That'll prove for under a $20 bill that it's not your oil.
 
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CleanSump

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The oil very much more than likely is not his problem in this. It wouldn't take 20,000 miles for a problem show up. It's something with the transmission, which wear and tear on that with M1 15w50 is no more or less than any other oil.

I like the idea of checking chain tension and BLS has a good idea for you in checking clutch adjustment.

Like I said what you were describing is not a oil related, it's something mechanical. For grins drain that oil (save it in a clean container, no sense wasting it if you're nowhere near an oci) and put in 15w40 T4. Betting dollars to donuts it does the same thing. That'll prove for under a $20 bill that it's not your oil.
"Of late have been noticing gear changes getting increasingly clunky after about half an hour of riding in hotter weather."
The oil he is using isn't meant for use in a motorcycle transmission sharing oil with the engine and clutch. Damage done.
 
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The oil he is using isn't meant for use in a motorcycle transmission sharing oil with the engine and clutch. Damage done.
I agree with Bonz... the problem is not oil related... employing oil not motorcycle specific does not automatically damage your gear box because the slight difference between Mobil MC specific oil and Mobil Auto oil is not enough to cause the reported damage...

M15w50AutoM20w50V2HD20w50.jpg
 
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RaymondP

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BusyLittleShop, appreciate the comparison. Very interesting. For info I don't think either of the two oils (M1 Auto vs M1 V2) are on spec for my 2013 Triumph Thruxton - 10W-40, 15W-50, API SH (or higher) AND JASO MA. I believe the MI V2 meets Harley V-twin specs. Mine is an inline twin with a capacity of 865cc. Why it should be different I don't know.

Deviations I see in the data you kindly provided are in the Phosphorus and Zinc. No idea what these two elements do for my engine/gearbox, but for info I have NOT experienced any clutch slippage, even on hard acceleration? Bike is modified including a tune for +72 hp. :)

Sorry for asking a favor, but if not too much trouble would it be possible to see same comparison with Mobil 1 on spec oil. I believe this is the one that meets the spec. Mobil 1 4T 1-W-40 Just curious as to the differences, and in particular with what I have been using up to now as you have illustrated ...Mobil 1 15W-50 syn. auto.

Really appreciated, thank you, RaymondP, (the OP)
 
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That is an absolutely excellent oil choice. Furthermore, it is extremely unlikely your transmission gears and bearings are worn out at 20K miles especially with the use of such a robust oil. M1 15W-50 is well known in racing circles for being able to handle high temperatures, the shear of gearboxes and heavy loads of turbocharged engines.

I'm guessing that your "bump" related issue is not transmission gear or bearing failures, but something mechanical.

There are known shift mechanism issues with some of these bikes. As I understand it (I've not seen it) they are relatively easy to repair.
 
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Compared to M1 15W-50, M1 motorcycle oils generally have a bit more ZDDP and 'might be' a bit more shear resistant. Although that last part is, to the best of my knowledge, unproven. Way too many people have great results with the automotive oil in motorcycle applications.

But any motorcycle with a shared sump and transmission will experience oil shearing, and the subsequent shift feel changes. I don't believe that ZDDP levels affect shift quality. There is a reason some motorcyclists change oil frequently, gearbox related shear.
 
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Deviations I see in the data you kindly provided are in the Phosphorus and Zinc. No idea what these two elements do for my engine/gearbox
Sorry for asking a favor, but if not too much trouble would it be possible to see same comparison with Mobil 1 on spec oil
Really appreciated, thank you, RaymondP, (the OP)

You're welcome Raymond... I will ante up what I have prepared between Mobil 1 10w40 auto and 10w40 Motorcycle...

As riders we need to understand the way additives live and work...

Under extreme conditions, the Zinc and Phosphorus compounds
are sacrificed to prevent wear, particularly between cylinder
bores, piston rings, gears. However - and this is the important
part to remember available research shows that more Zinc & Ph does
not equal more protection, it merely extends the protection against
metal-to-metal contact. Under normal conditions Zinc & Ph are not
sacrificed and end up being wasted during oil change... so much for
those higher PPM numbers...

Blackstone Labs has got the data that the level of additives don't
have an awful lot to do with wear nor that 50 grade wears better than 40
grade... so either the M1 Auto or M1 MC or 40 / 50 grade will meet and
exceed your mileage expectations...

Mobil10w40V4T10w40.jpg
 

RaymondP

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You're welcome Raymond... I will ante up what I have prepared between Mobil 1 10w40 auto and 10w40 Motorcycle...

As riders we need to understand the way additives live and work...

Under extreme conditions, the Zinc and Phosphorus compounds
are sacrificed to prevent wear, particularly between cylinder
bores, piston rings, gears. However - and this is the important
part to remember available research shows that more Zinc & Ph does
not equal more protection, it merely extends the protection against
metal-to-metal contact. Under normal conditions Zinc & Ph are not
sacrificed and end up being wasted during oil change... so much for
those higher PPM numbers...

Blackstone Labs has got the data that the level of additives don't
have an awful lot to do with wear nor that 50 grade wears better than 40
grade... so either the M1 Auto or M1 MC or 40 / 50 grade will meet and
exceed your mileage expectations...

View attachment 112376
Thank you, Larry. So nice to get clear, concise and understandable feedback from someone knowledgeable. For some reason so many oil discussions seem to descend into hostile rants. Good to see none of this in this series of posts.

From what I am gathering there appears to be unanimous support for me to continue using the Mobil 1 15W-50, so I plan to do so. At around $25 for 5qts. from Walmart seems like a reasonable solution given the higher cost of motorcycle specific M1 at $11 per qt (10W-40 4T). I also have a preference for the 15W-50 weight.

Once again, a big thank you. RaymondP
 
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There are plenty of MC specific oils that have lower zinc content than mobile 15w50. It's not an additive issue. Oil heats up and so do engine components in a shared sump.

It's not a logical stance to say it's due to the rating of the oil. Nobody's going after anyone, This is simply discussion. BLS and I have had it out plenty of times but when we do agree it's from personal experience, applied logic and reading others experience on this forum.

However, BLS, the 10W-40 4T data you posted is the outdated data again...
 

FZ1

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I have an air-cooled 2013 Thruxton with about 20K miles. Old technology, but with EFI. Inadvertently started an impassioned debate on appropriate oil at the Triumph Rat forum. The bike has a wet clutch and the manual recommends 10W/40 or 15W/50. Manual also specs API SH (or higher) AND JASO MA.

Have been using Mobil 1 15W/50 @ 4K oil change intervals up to now and seemed fine. I do not ride in temps much below 45degrees, mostly 60/70/80+. Of late have been noticing gear changes getting increasingly clunky after about half an hour of riding in hotter weather. No clutch slipping! Of more concern is the trans seems to react to bumps in the road. Almost feels like it is going to implode, or the back half of my bike is going to fall off. This feeling is through my seat and only happens when riding over bumps. The ride immediately returns to normal after the bump. Very disconcerting.

With the focus on oil on this forum, thought I would reach out to the collective membership's expertise/experience for opinion. Some forum members are blaming incorrect oil selection. The oil I have been using is NOT JASO MA but many have attested to it working fine for their bikes. I am not particularly knowledgeable on all the spec abbreviations/standards and their implications! Link to M1 product info herewith..... M1 15W-50

Thanks in advance for any advice.
All I can tell you is that Amsoil 20w-50 MC oil shifts better than M1 10-40 MC oil. Fresh oil shifts better than old oil. YMMV.
 
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Thank you, Larry. So nice to get clear, concise and understandable feedback from someone knowledgeable. For some reason so many oil discussions seem to descend into hostile rants. Good to see none of this in this series of posts.

From what I am gathering there appears to be unanimous support for me to continue using the Mobil 1 15W-50, so I plan to do so. At around $25 for 5qts. from Walmart seems like a reasonable solution given the higher cost of motorcycle specific M1 at $11 per qt (10W-40 4T). I also have a preference for the 15W-50 weight.

Once again, a big thank you. RaymondP

You're welcome Raymond... however I would choose the 40 over the 50 because
a 40 flows faster with less energy than a 50 which means a 40 will increase
horsepower and decrease operating temps with no loss in longevity...

full-45634-35394-viscositytest1.jpg
 

ZeeOSix

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Of late have been noticing gear changes getting increasingly clunky after about half an hour of riding in hotter weather. No clutch slipping! Of more concern is the trans seems to react to bumps in the road. Almost feels like it is going to implode, or the back half of my bike is going to fall off. This feeling is through my seat and only happens when riding over bumps. The ride immediately returns to normal after the bump. Very disconcerting.
Sounds like your chain is too tight, and/or there is a suspension problem or mis-adjustment. Transmissions just don't "react to bumps in the road".
 
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