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DGV weber jets in ZX9R
Craigorypeck - 17/1/11 at 10:42 PM

Are they a direct fit???

I have 180 jets (that were in the carbs when bought) as suggested by nearly all bike carb conversionees for a 2.0, and I'm running a 9:1 on my afr meter on WOT so I'm way way tooooo rich.

Gonna reduce jets to a 160ish maybe and try again..

OR- Should I consider leaving the 180 jets in and drilling a 1mm hole in the blocked air jet?? Will this have the same effect or will it effect the fuelling more up the rev range like air correctors do in dcoe stacks..?


Yazza54 - 18/1/11 at 08:34 AM

Dunno about the jets but that is massively rich! What are you goin to tune it to?

14.7:1 is mentioned alot but for max performance I've read you should be looking between 12.5-13.5


Craigorypeck - 18/1/11 at 03:51 PM

It's nearer what dragsters run... lol!

I have ordered some small drills that will be used to rebore soldered jets, then prob buy the weber ones that are the same size and go from there to start. as it's so rich I'm might take out the blocks in the air jets but dont know if that would have a linear effect or just top end leaning.. more reading me thinks


woolly - 18/1/11 at 08:09 PM

there are two camps those that block the air corrector and those that don't.
my choice was to have the air correction as it helps atomize the fuel.
best go back to the original size air jet and start again the air correction works just about over the whole range. most noticeable around 40 - 80% throttle.
you 1.8 main would be a starting point if adjustable height needles then in the middle, sound like you use a wideband O2 so drive it and adjust as required. had a friend as passenger to write down the readings as i drove, cheap data logger
it does take a fair while but alternative is a rolling road and cost.

i enjoyed doing mine but would like to profile my own needles just to finish it of. one day i will learn how to do it.


Craigorypeck - 18/1/11 at 08:41 PM

Thanks! I may be in the later camp.

I found a 1.6mm drill this eve and reemed out the original jets didn't take much.

Went another spin and its sitting around 11.5ish on WOT, still way too rich.

Idles well at 14.5 tho

There is a lot of outward spray coming from the needle when lifting off idle.
The emulsion tubes may be worn but I cant really see... Needles in the middle atm

[Edited on 18/1/11 by Craigorypeck]