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post #9 of (permalink) Old 06-02-2010, 07:37 AM
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Joined: Sep 2008
From: Blackfoot, ID (~5,000' AMSL)
I Ride: 00 ZX-9r Lime Green 02 ZX-9r Lime Green, California E1 & F1 models, respectively

Posts: 9,979
3 or 3+

No. You'll just be masking the issue and wasting fuel.

There may be another problem. Either the pilot air screws (springs, copper & O-ring washers) were not installed from underneath the carb, causing one or more to pop off during installation (common if installed horizontally) or you have an air leak around your carbs/intake boots.*

Inspect the screw assemblies. You can do that while the carbs are on the bike. Just unscrew them. All four components (above) should come out together. Then insert and seat them while the carbs are on the bike to guarantee that nothing pops off and gets squashed. Remove the carbs and set the pilot air screws uniformly (usually 1.5 - 2.0 turns), snug down the carb boot clamps and sync your carbs.

Also consider raising the jet needle (moving the clip down one notch) or placing a 0.8mm shim washer under it. This will effectively enrich mid-range, but should also help the low-end fuel circuit out if needed.

* your description of 'runs better hot' is classic lean

Alright! Trading bikes for a while was fun.I'm ready for mine back. No, seriously, get off my bike. Ahh, what a privilege it is to have such a sweet ride.
At the track she's said to be outclassed, but on the street, she reigns unmatched. She's the only big-bore canyon carving hypermiler I know of. -- Picture gallery, K&N air filter, SuperTrapp Aluminum Racing Series exhaust (Made in USA), ZG touring shield, & otherwise stock.
Science & OODA literate. ACA covered.

Last edited by e1_ZX-9r; 06-02-2010 at 05:51 PM.
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