• Yamaha made several models of Apex snowmobiles in 2007.jet ski image by Paul Moore from Fotolia.com
  
  Yamaha Motor Corporation, the Japanese company that first began making motorcycles in 1954, introduced its first production-model snowmobile, the SL351, in 1969. The company's 2007 line of Apex snowmobiles include the GT, the Mountain, the Mountain SE, the RTX and the RTX with Reverse. They all have four-cylinder, liquid-cooled machines with fuel injection, rear exhaust and wide, saddle-less plastic mountain skis.
  
  

Engine

• Yamaha's 150-horsepower 2007 Apex snowmobiles have four-stroke, four-cylinder, 998 cc engines. Besides being liquid cooled and having 74 x 58 mm bore and stroke, Apex engines have a three-valve intake design, 39 mm Mikuni fuel injection, digital TCI with throttle position sensor, rear exhaust, a YVXC drive clutch and a variable-ratio clutch/transmission. Their 4-piston hydraulic disc brakes have a lightweight rotor.
  
  

Chassis

• The 2007 Yamaha Apex models have independent, double-wishbone front suspension, 7-inch front travel, wide saddle-less plastic mountain skis, standard carbide ski runners and a stabilizer bar. The Apex models also have gas cell hydraulic rear shocks, 14-inch rear travel and 40 mm HPG, aluminum front shocks.
  
  

Fuel and Oil

• Yamaha's Apex models have a 10-gallon fuel capacity, 3-qt. oil capacity and they take regular unleaded fuel, as well as Yamalube 4, 0W-30, cold-weather formula engine oil.
  
  

Features

• The 2007 Apex one-seaters have 10-position hand and thumb warmers. Besides standard rear carrier racks, they have two 60/55W halogen headlights. Controls include standard digital speedometer, odometer, tripmeter and digital tochometer.
  
  

Models

• Yamaha's 2007 Apex models include the ER (manufacturer's suggested retail price of $10,199 as of 2010); the GT ($11,199), the Mountain ( $10,799), Mountain SE ($11,299), the RTX ($10,299) and the RTX with Reverse ($10,599). The models vary from one another slightly in their length, maximum ski stance, height, length, weight, track length and width and lug height.