Legendsforce Legends Cars Engines Information

Legends are now competing in the United States with three engines in the class. The YAMAHA FJ1200, XJR1200, XJR1250 (Sealed). A YAMAHA FJ1200/XJR1200 from other countries (Canada, England) or an FJ1100 may only be used if it meets all the specifications of the current U.S. model as delivered through 600 Racing Inc. They are air cooled 4-stroke running on pump gasoline. Yamaha recommends the use of 89 octane unleaded gasoline. Gasoline additives are closely scrutinized. Such substances as oxygen or nitrogen bearing agents (including propylene oxide) are prohibited. By the rule book, the engine must remain a factory-stock engine. The compression ratio can not exceed 10.0:1. The cranking compression must be below 180 p.s.i. at any time (hot or cold) on at least 3 cylinders with the ignition off and throttle wide open. A controversial new rules is going to be in effect for 2002, where all the spark plugs will now be removed to test cranking compression, instead of removing the one spark plug on the tested cylinder. This will ultimately cause a higher cranking compression than previously attained by the old method of testing due to a higher cranking speed. A slotted cam sprocket can be installed for tuning, and advancing the intake timing increases the compression.

The valve lash can be used as a tuning device. The valves are adjusted by bucket and shim. The best starting point would be, .006 intake, and .008 exhaust. You can lower the lash by .002 to give the engine more top end power, or do the opposite for low end power.

The cylinder bore cannot exceed 77.57mm or 3.054" (maximum .022" overbore from stock).

The carburetors are Mikuni BS36 x 4 constant vaccum. Re-jetting is permitted. The engines are mounted 90 degrees counter to the way Yamaha designed them to be cooled by air flow. The #3 cyl. is a common problem area on these engines due to heat and the restricted air flow to the back cylinders. Have the carbs tuned to keep #3 and #4 from running lean. Venting fenders and hoods, while staying within rules, is recommended. See the FACTORY Professional Tuning Components website for good information on performance carburation setup.

The ignition is 12v battery powered, inductive, digital, magnetically triggered. Recommended spark plugs are the NGK DP8EA-9 or ND X24EP-U9 for US models.

The sequential gearbox in the engine is a constant mesh 5-speed, wet clutch.
Gear Ratio:
1st - 40/14 (2.857)
2nd - 36/18 (2.000)
3rd - 33/21 (1.571)
4th - 31/24 (1.291
5th - 29/26 (1.115)

From the Forums I have read, and talking to other racers, you can use a wide variety of quality conventional or synthetic motor oils. These engines run hot, and it is recommended that the oil be changed every 2 to 3 outings under these extreme conditions. I have ran AMSOIL Series 2000 Synthetic 20W-50 Racing Oil for the last couple of years with good results, although a little expensive. This or Torco MPZ Synthetic 20-50 Racing Oil are good choices.


Engines Chassis Tires Saftey Gearing Sponsorship Links Legends Groups Legendscars Legendstech	Legends are now competing in the United States with three engines in the class. The YAMAHA FJ1200, XJR1200, XJR1250 (Sealed). A YAMAHA FJ1200/XJR1200 from other countries (Canada, England) or an FJ1100 may only be used if it meets all the specifications of the current U.S. model as delivered through 600 Racing Inc. They are air cooled 4-stroke running on pump gasoline. Yamaha recommends the use of 89 octane unleaded gasoline. Gasoline additives are closely scrutinized. Such substances as oxygen or nitrogen bearing agents (including propylene oxide) are prohibited. By the rule book, the engine must remain a factory-stock engine. The compression ratio can not exceed 10.0:1. The cranking compression must be below 180 p.s.i. at any time (hot or cold) on at least 3 cylinders with the ignition off and throttle wide open. A controversial new rules is going to be in effect for 2002, where all the spark plugs will now be removed to test cranking compression, instead of removing the one spark plug on the tested cylinder. This will ultimately cause a higher cranking compression than previously attained by the old method of testing due to a higher cranking speed. A slotted cam sprocket can be installed for tuning, and advancing the intake timing increases the compression. The valve lash can be used as a tuning device. The valves are adjusted by bucket and shim. The best starting point would be, .006 intake, and .008 exhaust. You can lower the lash by .002 to give the engine more top end power, or do the opposite for low end power. The cylinder bore cannot exceed 77.57mm or 3.054" (maximum .022" overbore from stock). The carburetors are Mikuni BS36 x 4 constant vaccum. Re-jetting is permitted. The engines are mounted 90 degrees counter to the way Yamaha designed them to be cooled by air flow. The #3 cyl. is a common problem area on these engines due to heat and the restricted air flow to the back cylinders. Have the carbs tuned to keep #3 and #4 from running lean. Venting fenders and hoods, while staying within rules, is recommended. See the FACTORY Professional Tuning Components website for good information on performance carburation setup. The ignition is 12v battery powered, inductive, digital, magnetically triggered. Recommended spark plugs are the NGK DP8EA-9 or ND X24EP-U9 for US models. The sequential gearbox in the engine is a constant mesh 5-speed, wet clutch. Gear Ratio: 1st - 40/14 (2.857) 2nd - 36/18 (2.000) 3rd - 33/21 (1.571) 4th - 31/24 (1.291 5th - 29/26 (1.115) From the Forums I have read, and talking to other racers, you can use a wide variety of quality conventional or synthetic motor oils. These engines run hot, and it is recommended that the oil be changed every 2 to 3 outings under these extreme conditions. I have ran AMSOIL Series 2000 Synthetic 20W-50 Racing Oil for the last couple of years with good results, although a little expensive. This or Torco MPZ Synthetic 20-50 Racing Oil are good choices.