10w-40 vs. 10w-50

Dezertpilot

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Ok so in my continuing quest for as good but priced cheaper 4 stroke oil I have come across Mobil 1 10w40. My bike calls for 10w-50, can I safely run 10w-40 in my bike? I know one oil is thicker and one is thinner, but not quite sure what is what. I dont want to blow my bike up at the cost of saving $7 or so a quart, I just want to be safe, thanks!
 

bajaxp

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Ok so in my continuing quest for as good but priced cheaper 4 stroke oil I have come across Mobil 1 10w40. My bike calls for 10w-50, can I safely run 10w-40 in my bike? I know one oil is thicker and one is thinner, but not quite sure what is what. I dont want to blow my bike up at the cost of saving $7 or so a quart, I just want to be safe, thanks!
It depends on what year your KTM is. Mine is a 2007 and the engine and transmission/clutch share the same oil and the Mobil 1 or any 'car oil' won't work. This is because 'car oil' has what is called friction modifiers (SJ rated and up) and it will wreck your clutch...failure mode...slipping clutch. But I think the newer KTM engines have seperated the engine oil from the clutch/transmission oil like Honda did and it work fine in the engine side...just don't put it in the clutch/transmission side.

But at the end of the day, dirt bikes don't hold much oil, so even Motorex at $15/qt plus filters equals something like a $30 oil change. Not cheap...but cheap insurance. Mobil 1 is probably the best readily availible 'car oil' on the market, but my $.02 is that I would stick with the factory speced Motorex 10W-50. Plus 3bros needs the business! :)
 
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PBR

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It depends on what year your KTM is. Mine is a 2007 and the engine and transmission/clutch share the same oil and the Mobil 1 or any 'car oil' won't work. This is because 'car oil' has what is called friction modifiers (SJ rated and up) and it will wreck your clutch...failure mode...slipping clutch. But I think the newer KTM engines have seperated the engine oil from the clutch/transmission oil like Honda did and it work fine in the engine side...just don't put it in the clutch/transmission side.

But at the end of the day, dirt bikes don't hold much oil, so even Motorex at $15/qt plus filters equals something like a $30 oil change. Not cheap...but cheap insurance. Mobil 1 is probably the best readily availible 'car oil' on the market, but my $.02 is that I would stick with the factory speced Motorex 10W-50. Plus 3bros needs the business! :)
well said, cheap insurance. you have a $9000+ street legal race bike that needs the best oil to keep it alive and well. your bike only takes 600cc's of oil in the engine, i don't get why anyone would search to find a "cheaper" oil. ht-racing also makes an oil cooler that will give you more oil capacity and longer change intervals.
 

Dezertpilot

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No I'm using the 4 stroke mobil 1 racing oil, it is ok in the trans because it is jaso or something rated. I'm over the motorex it can't be be twice as good as another fully synthetic oil. Thank for the replys guys!
 

Dezertpilot

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well said, cheap insurance. you have a $9000+ street legal race bike that needs the best oil to keep it alive and well. your bike only takes 600cc's of oil in the engine, i don't get why anyone would search to find a "cheaper" oil. ht-racing also makes an oil cooler that will give you more oil capacity and longer change intervals.
I'm going to get the HT cooler after I get my suspension done, rekluse, etc.
 
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