Spark Plugs - The Savage is a low tech engine and just about any spark plug works fine.  I use either of these:
NGK DPR8EA9
NGK IRIDIUM DPR8EIX-9

Oil - I use Shell Rotella 15W-40.  Walmart, TSC, wherever it is on sale. You can also use Shell Rotella T-6 synthetic if you want to spend a bit more. You can add a ZDDP additive if you wish, you can find long discussions about this issue.

Rush-rks wrote on 08/22/13 at 10:30:11:


Most of us that have been around a while don't trust or use the factory oils anymore.  As the motorcycles are refined and redesigned, the oil is changes as well.  Modern motorycles are being equipped with catalytic converters, fuel injection and oxygen sensors.....and the amount of ZDDP that our primitive engine needs to survive are being taken out of the oil so that the oxygen sensors and catalytic convertors will not be fouled by the Zinc and Phosporous.  I have no idea how much ZDDP might still be in the Suzuki Oils.  The Suzuki Savage engine is a flat tappet concept...where the rocker arms rub agains the cam profile without the benefit of any rollers - and ZDDP content of about 1,200 - 1,400 ppm is the minimum amount we believe is required.

To be safe...we recommend the following oils on this forum:
  http://suzukisavage.com/cgi-bin/YaBB.pl?num=1344471565

Filters? Emgo, Hi Flo HF137, K&N KN137 for oil. Emgo or K&N for air filter.

Dealer filters are the same basic unit as Emgo, just cost a lot more. Order a years worth at a time if you have to mail order them. But, even NAPA carries K&N motorcycle filters, at least around here, including the KN137.

Anything else you source from Emgo is suspect, but even major Big 4 dealerships in WA got Emgo units from where I worked for the service bays to use. DIY types got Emgo filters in O.E.M. boxes...