01 800 zx carbs vs 03?,04 & newer carbs: main jet style differences & other changes

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flatlander72

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Sep 5, 2008

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wisconsin

• Jan 11, 2009

• #1

01 800 zx carbs vs 03?,04 & newer carbs: main jet style differences & other changes

transplanting engine into 99 gen 2 pol & airbox won't work without major remodel. told if i run pods these carbs won't work well but newer ones will. looking to find out what internal carb changes i need to make to convert to newer style carbs if possible. thanks for any info. up to this point swap has gone easier than i figured it would. 151x16x2.5 stuffed into tunnel

 

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hymark860

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Jan 10, 2002

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PF, Idaho

• Jan 11, 2009

• #2

Newer carbs have the hooded needle jet. Started in the 03 on the summits. 01 carbs cames with 500 mj. The 03 and 04 were 420s give take a size depending on year.

The pilots were the same on all years. 17.5 If you run pods might need to go to 20s or you'll get a lean bog. Newer carbs also had a adj needle. start in the middle. Start 500 or 490 on the mainjet and work down.

 

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Flit8.0

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Nov 28, 2007

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Evans, WA

• Jan 11, 2009

• #3

I have an '01 800 (in a ZX) and I run pods. Seems to work fine for mine.

 

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flatlander72

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wisconsin

• Jan 12, 2009

• #4

thanks for the info. Hymark, when you say a hooked needle jet what does that mean? Also is the jet needle the same profile or different along with being adjustable? Flit, did you change anything else besides the pilot, did you go up on the main also?

 

Summit8

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Oct 13, 2001

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Fairview, MT

• Jan 12, 2009

• #5

Hooded needle jet sticks up from the bottom of the intake venturi of your carbs. 02s were non-hooded also, ran like crap. Had mine rebuilt with hooded NJs and adj. needles, dpm removed, carbs vented to the airbox, adj. power-jets on carbs. Works great.
Xtreme Perf. in CO was doing this fix for the Doo carbs years ago, the fix info is still listed on their website I believe.

 

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flatlander72

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wisconsin

• Jan 15, 2009

• #6

carbs: other ideas

After the carbs are changed to newer style did you have to do anything to the brain box or just left it alone. I've been told you should get it reflashed, do you need to or is it optional? Any other tuning changes if you boost compression for high elevation, 7,000 and up?

 

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hymark860

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Jan 10, 2002

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PF, Idaho

• Jan 16, 2009

• #7

No reflash is necessary but the 02 had flashes to comp for the crappy carbs. you might want a 03 or 04 timing curve. i don't know how different the needle it, but it works.