Racing fuel bad for carb?

3 replies to this topic
  • yz400fl1

Posted December 07, 2004 - 08:39 AM


I was just cruisin' TT and read the the resent post yz400 hp, and read the review of the 98' 400f http://www.motorcycl...yam/yz400f.html. I found one part that said that racing fuels hurt the carb. I have a 99' 400f and have been running VP 110 leaded for the last year. The bike runs better than new. And I asked the dealer they said they didn't know except that the leaded is good for the top end. Anyone have opinions on this?

  • yz400fl1

Posted December 08, 2004 - 06:46 AM


Nobody knows?

Visit the ThumperTalk Store for the lowest prices on motorcycle / ATV parts and accessories - Guaranteed
  • 642MX

Posted December 08, 2004 - 05:05 PM


All I know is I've run Citgo 110 leaded for a long time with no problems. I heard lead cushions the valve against the seat, I don't know if this is true or not. As far as carb problems go, I've never had any troubles, never even had the carb off my bike or changed any jets.

  • Silver Surfer

Posted December 09, 2004 - 04:31 PM


the original purpose of leaded fuels, before they came up with hardened valve seats, was to create a better seal around the valves and the seat. with better metals, and tougher emissions laws, we now have unleaded gasoline.

i don't think your carb will be affected...but this thread has some GREAT info...

Related Content


yz250x vs 450 4t comparisons (preferably desert riding) needed by JakeNorthrupYZ450F

Dirt Bike   Make / Model Specific   Yamaha   Yamaha 2-Stroke
  • 9 replies

Michigan Motocross Tires by 288yz450

Dirt Bike   Dirt Bike Regional Discussion   North
  • 1 reply

YZ450F 03 Sparks driving me crazy by SirAttard

Dirt Bike   Make / Model Specific   Yamaha   YZ 400/426/450
  • 5 replies

Is the 2016 GYTR Yamaha YZ450F too fast? by Fryboy

Dirt Bike   Special Interest Forums   Pro Racing
  • * - - - -
  • Hot  241 replies

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.