Jets and needles

Hi,

I recently decided to dismantle a set of carbs for cleaning and new gaskets out of boredom and discovered that they have the wrong size jets in and adjustable needles. It appears to have been rejetted severely down.

Original size is 112.5 and it has 87.5 installed. An upgrade for more fuel would be 114 to 118 max usually for these carbs and down to 110 for frugality.

I have a set of 122.5 jets that are a straight swap.

Mys question is could i put them on and then move the needle down a notch or 2?

The main jet mainly controls fuelling at top end throttle openings, typically above 6000rpm, though it does affect mid range as well. Lifting the needles will richen the mixture above 3000rpm. Pilot jets control tickover and up to 3000rom as well as airscrews. They all affect each other at the overlap phase.

courtesy of [mention]ThePhatomfart[/mention]

Is this on the FZR?

They suffer from emulsion tube wear and run rich, mine did and I had to replace them ,genuine only when I did mine.

Is this on the FZR?

They suffer from emulsion tube wear and run rich, mine did and I had to replace them ,genuine only when I did mine.

The carbs are off the rf900, i have doner jets from the fzr as i am boring it it to 1040 and increasing the jet size. I believe the carbs on my rf were replaced either off the 400 or off a Japanese bike at some point as they had different regulations in the 90s for their bikes.

I swapped the jets cleaned the carbs well and moved the needle down a grove and and it's running really well, buckets more power and no more bogging in the high rpms.