leaded gasoline in a YZ450F?

4 replies to this topic
  • CBreaken

Posted July 17, 2004 - 11:58 AM


I was just looking through the owners manual for my 04 YZ450F and noticed under the "FUEL" section it says not to run any leaded gasoline because "use of leaded gasoline will cause severe damage to the engine internal parts such as valves, piston rings, and exhaust system, etc." Is this true, or is it just some enviornmental scare tactic forced upon Yamaha? I've been running 50/50 76 premium pump gas/VP red for the last 6 months with no porblems, but then again I haven't tore down and inspected the engine either. Any thoughts and or experiences would be appreciated. Thanks.

  • Wyatt

Posted July 17, 2004 - 02:07 PM


I ran leaded race fuel in my '01 which had a ton of hours on it with zero problems. I also run it in my '04. No prolblems.

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • dvn

Posted July 17, 2004 - 02:41 PM


I've run a 50/50 mix of leaded race fuel and super unleaded in my 01' 426 from day one with no problems at all. I remember reading somewhere that the lead in the fuel helps to cushon (spelling?) the valve seats. Don't know if thats true or not but I haven't had to adjust my valves yet with over 80 hrs. on it.

  • CBreaken

Posted July 17, 2004 - 03:00 PM


Thanks for the replies guys. Actually the whole reason behind my running the 50/50 blend was because of the leaded fuels tendency cushion the valves at the seats. I know that I wouldn't gain any performace, just looking for long term reliability. It was my understanding that leaded fuels were only harmful to catalytic converters and O2 sensors. I wonder why yamaha added that disclaimer into the manaul :thumbsup:? I know leaded fuel leave behind more deposits. Could this be why it's considered harmful?

  • twistngrip

Posted July 17, 2004 - 06:53 PM


I think they say no lead for a reason. Why go with lead when it runs great on unleaded and it will obviously last a long time with unleaded. Just my .02.

Related Content


The "going back to the other darkside" adventure... by Monk

Dirt Bike   Make / Model Specific   KTM   250/350/450/505 SX-F & XC-F (4-Strokes)
  • Hot  113 replies

Michigan Motocross Tires by 288yz450

Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply

Wilson the Blue Privateer by jetfuel

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  50 replies

Yamaha YZ450F 2017 by Chris.GVS

Yamaha YZ450F 2017
  • * * * * *
  • 1 review
  • Last review by Tommyk_55
  • On Yesterday, 06:20 PM

Thinking about Yamaha 250... by Arctic Pride

Dirt Bike   Special Interest Forums   Pro Racing
  • Hot  491 replies

Join Our Community!

Even if you don't want to post, registered members get access to tools that make finding & following the good stuff easier.

If you enjoyed reading about "" here in the ThumperTalk archive, you'll LOVE our community. Come join ThumperTalk today!

The views and opinions expressed on this page are strictly those of the author, and have not been reviewed or approved by ThumperTalk.