The klx 140 uses sae 10w-40 oil
type of oil to use in a 2007 klx 110
No, KLX 110 plastics will not fit a KLX 140. Although both bikes are part of the Kawasaki KLX family, they have different frame designs and dimensions, leading to incompatibility in their plastics. Each model has specific bodywork tailored to its unique structure, so it's best to use parts designed specifically for the KLX 140.
I use 85-140 but as long as it is a good oil you can use 80-90W.
75w-140
You can use any kind of 10w-40 oil for a nighthawk
Baby oil
Most use Synthetic Oil.
Rocket oil
the answer to that is unknown to man kind
They use the oil God gave them in their oil glands.
synthetic oil
What are you substituting the oil with? What kind of recipe? You couldn't use butter for the oil in salad dressing. Sometimes it does matter what kind of shortening you use.