Technical Insights; first seen in Kawasaki Dual Sport News Feb./Dec. 1997 now found on

There have been lots of bad ideas furnished to KLR riders on the internet. Three of the
worst are:


  • Replace your 08/09 strong forged thick bladed “doohickey” with a weaker machined
    aftermarket copy of the original.
  • Equip your KLR650 with 16/43 final gearing which is likely to decrease engine life
    and lower your fuel mileage (have you heard of “pumping losses” and lugging your
  • Use diesel oil like Shell Rotella in your engine.

Well, the motorcycle manufacturers have finally caught wind of the diesel oil craziness.
The owner’s manual for Top Gun’s new 2009 Yamaha WR250R says the following about
engine oil:

NOTICE:  Do not use engine oil additives; they may cause clutch slippage. Do not use oils
with a diesel specification of “CD” or oils of a higher quality than specified. In addition, do
not use oils labeled “energy conserving II or higher”.

Any of the top motorcycle engine oils made by Spectro, Belray, Mobil (not car Mobil 1),
Honda HP4, or Maxima, for instance, will do the job as long as they are API rated for
service “SG” or higher and have a “JASO” standard “MA”.

Only oils formulated for use in motorcycle engines with integrated transmissions and
clutches can withstand the shearing forces that will quickly breakdown an oil blended for
use in gasoline and diesel truck or car engines. You would be amazed how quickly your
KLR650 engine can take a diesel engine oil from say 20W-50 down to 20W.

Like John Arbuckle says, “you get what you pay for”. What no one wants to pay for is a
pre-mature engine rebuild.