Quote:
book says 15-50w I have only found 10-40 & 20-50 which should I use??
Since your original question got kind of lost here (imagine that!!!  )
The book says 15w-50 or 10w-40.
I use 10w-40 full synthetic motorcycle specific oil year round.
Now it doesn't get too cold for too long here, but the summers get hot. 117 degrees typically.
I've had no problems with the 10w-40.
Contra todo mal, mezcal; contra todo bien, también
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