Newer Carb on an Older Bike?

2 replies to this topic
  • TurboDon

Posted December 01, 2013 - 10:32 AM


I have a 99 WR400


I'm in the process of rebuilding it and boring it to 426cc with a 13.5:1 piston and some mild head porting and 2003 style auto decompress cam.


The bike engine wise will basically be a healthy yz426.


I was looking to get away from the old style carb with all the octopus junk hanging off of it and upgrading to a newer yz carb.


Im sure there are plenty of you guys out there who have done this, so just wondering what you all think the best bet would be as far as what to go with.





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  • f150jokerstyle

Posted December 01, 2013 - 06:19 PM



This is pretty common minus the part of it not running right the first time.

  • TurboDon

Posted December 01, 2013 - 10:19 PM


Yeah after posting I realized at the top of the page there is a thread called "look here first commonly asked questions"


sure enough there was a carb upgrade thread.


from the looks of it the 02 carb is good if i didnt want to integrate the hot start mechanism on the bars.


And the 05+ carbs got updated internal circuitry and are better than their earlier predecessors.


It would be great if someone could confirm.

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