Carb Jetting

[breakinbarrs]

My daughter has an 03 rx and when temps get in the 30s it is real fat. Has anyone experimented with leaning these out a little with success?

 

[td0_06]

With higher temps usually comes more humidity = richer A/F ratio. If you wanted to get more exact then you need to change the main jets. But if its not fouling plugs or bogging down (almost like a backfire) then I wouldn't worry too much. Someone else on here who has more experience with the RX1 should be able to help you out more.
Good luck

 

[rxrider]

If she doesn't care to ride when it's cold, below zero F or -18C, I would jet down 1 step to 132.5 main jets. Leaving pilot jets and screws stock at 17.5 for the jets and 1-3/4 to 2 turns out from lightly seated for the screws.
What are the needles set at?
Get the carbs syncronized, it will have huge impact at idle and at partial throttle low speed operation.