What oil to run on my Suzuki s40
- Thread starter ram_man
- Start date
Thanks! You have the awesome benefit of the well established S40 forum. I'm sure you are a member by now.
What Papa Bear shared earlier from that forum is probably years worth of discussion summed up very nicely. Pick an HDEO in 15W40 that has a good zinc content and go with it.
I second the idea of T4 15w40, as an air cooled single will contaminate the oil and make it dirty much sooner than a more modern liquid coolant engine before you make it halfway to the recommended 6,000 mile OCI most likely. The benefit of a longer oil change interval with a synthetic as it relates to holding viscosity and shift quality is a moot point once the oil is dirty.
Keep the updates coming, this is an enjoyable thread.
Depends on how ridden. If 2 miles a day 5 days a week, that oil would probably be done @ 2000 miles (especially if a carb bike). If ridden every few weekends for 100 miles at a time, then it is probably fine up to the OEM interval.
Agree, I wasn’t meaning to imply the extreme short trip warm-up scenario was not worthy of consideration however that typically is not what most motorcycle oils endure. Bikes that get out each week for the summer months and end up with 1500 miles on the oil are disposing of oil sooner than needed is what I was hoping to get across.
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In your climate, as someone has mentioned, I would use the Valvoline Conventional 20w50 motorcycle oil. I was happy with it in my Suzuki C50.
I think oil in a shared sump has there things against it, the engine part with combustion and the primary part with clutch material, throw in the transmission metals too and why I changed my oil every 2000 to 3000 miles on my shared sumps bikes, actually I kind of do that in my non shared sump RK too, though I do not change the primary or transmission oil at those intervals and perfectly fine if I run longer on the engine, but I tend to change because of seasons, more then mileage, much like a boat, whether it needs it or not.
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I bought a 2019 this year, running ST 20w50 V Twin hoping to mitigate cam drive wear. FYI a friend put over 30k on one of these no cam tensioner fail.
Another good thought as to running 20w50, seems it’s hard to find a reason not to run either 20w50 or 15w40. Has anyone seen a VOA or UOA of ST 20w50 VTwin?
Your S40's valve train will thank you
T4, T5, or T6?
tight budget...10w-40 conventional bike oil on sale or respected 15w-40 hdeo oil
better budget...10w-40 synthetic blend or full synthetic bike oil
oil filter...oem Suzuki replacement or HiFlo Filtro
iirc...most metric cruiser/standard bike engines have automatic chain tension adjusters to minimize maintenance; I would contact a suzuki powersports dealer or trusted independent shop with concerns of timing chsin lash
better budget...10w-40 synthetic blend or full synthetic bike oil
oil filter...oem Suzuki replacement or HiFlo Filtro
iirc...most metric cruiser/standard bike engines have automatic chain tension adjusters to minimize maintenance; I would contact a suzuki powersports dealer or trusted independent shop with concerns of timing chsin lash
When going with a HDEO for wet sump bikes, make sure it meets JASO MA/MA2 for wet sump compatibility. T4/T5/T6 are self-certified and well proven there.
For a higher end oil Motul 7100 ticks off all of my checkboxes.
Great choice for a starter bike! At 18K it's probably due for a valve adjustment.
For a higher end oil Motul 7100 ticks off all of my checkboxes.
Great choice for a starter bike! At 18K it's probably due for a valve adjustment.