CRF's Only Forums

Please keep other info out of this thread. Only answer the questions. Copy and paste to keep format uniform.


Year:
Elevation:
Temperature Range:
Backfire Screen:
Air Filter:
Pilot Jet:
Main Jet:
Needle:
Needle Clip Position:
Fuel Screw Type:
Fuel Screw Setting:
AP Modified:
Leak Jet:
AP Cover:
Exhaust Type:
Exhaust Modified:

Year:07
Elevation:1000-5000
Temperature Range:25-100
Backfire Screen:yes
Air Filter: uni
Pilot Jet: 45
Main Jet:stock
Needle:stock
Needle Clip Position:stock
Fuel Screw Type:white bros
Fuel Screw Setting:approx 1 1/2 to 2
AP Modified:no
Leak Jet:stock
AP Cover:no
Exhaust Type:white bros e2 with s/a
Exhaust Modified:e2

Year: 07
Elevation: 0-1500
Temperature Range: 70's-90's
Backfire Screen: yes
Air Filter: Twin Air Powerflow
Pilot Jet: stock
Main Jet: stock
Needle:stock
Needle Clip Position: stock
Fuel Screw Type: Zip-Ty
Fuel Screw Setting:2 1/4 I believe
AP Modified: no
Leak Jet: stock
AP Cover: stock
Exhaust Type: stock
Exhaust Modified: no

Year:2007
Elevation:0 to 3000
Temperature Range:65-100
Backfire Screen:yes
Air Filter:Twin air
Pilot Jet:45
Main Jet:130
Needle:stock
Needle Clip Position:3rd
Fuel Screw Type:crfs only
Fuel Screw Setting:1 1/2
AP Modified:yes solid wire
Leak Jet:45
AP Cover:no
Exhaust Type:BBR HT
Exhaust Modified:BBR header and slip on

Year: 2008
Elevation: 500-6000'
Temperature Range: 45-100*
Backfire Screen: Yes, but will remove
Air Filter: Stock
Pilot Jet: 42
Main Jet: 140
Needle: JD Red
Needle Clip Position: 3rd
Fuel Screw Type: Stock
Fuel Screw Setting: 1 1/2
AP Modified: Yes, thick ring
Leak Jet: Stock
AP Cover: Stock
Exhaust Type: Stock
Exhaust Modified: No

Year: 2007
Elevation: 0-1500
Temperature Range: -10 to 90
Backfire Screen: not any more
Air Filter: Twin Air powerflow
Pilot Jet: 40
Main Jet: 135 (summer) or 138 (spring/fall)
Needle: NHNT currently
Needle Clip Position: 3rd or 4th
Fuel Screw Type: Zip-Ty
Fuel Screw Setting: 2.25-2.5 turns out
AP Modified: Yes
Leak Jet: stock
AP Cover: stock
Exhaust Type: stock
Exhaust Modified: nope

Year:2008
Elevation:250
Temperature Range:70-95
Backfire Screen:not for long
Air Filter:stock
Pilot Jet:42
Main Jet:
Needle:stock
Needle Clip Position:stock
Fuel Screw Type:stock
Fuel Screw Setting:2 1/2 turns
AP Modified:not yet
Leak Jet:stock
AP Cover: stock
Exhaust Type: stock
Exhaust Modified: nope

Year: 2008
Elevation: 900
Temperature Range: 80ish
Backfire Screen: yes stock
Air Filter: stock or no-toil
Pilot Jet: 45
Main Jet: stock
Needle: stock
Needle Clip Position: stock
Fuel Screw Type: scott
Fuel Screw Setting: 2 out
AP Modified: just large o-ring
Leak Jet: stock
AP Cover: stock
Exhaust Type: stock
Exhaust Modified: stock

The 45 pilot helps a ton with starting. I installed the JD kit but like the stock jetting a bit more. More hit and reved faster. I could have adjusted the JD kit, I think it was rich but I was happy with the stock settings with the 45. I might try the JD kit for ice racing a softer hit may make the bike easier to ride on the ice.

Year: 08
Elevation: 0-1000
Temperature Range: 10-40
Backfire Screen: stock
Air Filter: no toil
Pilot Jet: 45
Main Jet: 138
Needle: stock
Needle Clip Position: stock
Fuel Screw Type: stock
Fuel Screw Setting: 2-2 1/2
AP Modified: not yet
Leak Jet: stock
AP Cover: stock
Exhaust Type:hgs
Exhaust Modified: system

Year: 2007
Elevation: 600ish
Temperature Range: 30-90*F
Backfire Screen: Yes
Air Filter: Twin Air and OEM
Pilot Jet: 48 winter 45 summer
Main Jet: 138 winter 135 summer
Needle: Stock
Needle Clip Position: Stock
Fuel Screw Type: Adjustable, Talon brand (I think)
Fuel Screw Setting: 1 3/4
AP Modified: Wired - Best result
Leak Jet: 45, AP must be wired to get a strong squirt that doesn't last too long
AP Cover: stock (NGK 858 3.7 AP diaphram [ground nipple basically])
Exhaust Type: Stock
Exhaust Modified: Stock
Bog: Nope

Year: 2007
Elevation: 0-2000
Temperature Range: 50-90
Backfire Screen: yes
Air Filter: No-toil
Pilot Jet: stock
Main Jet: stock
Needle: stock
Needle Clip Position: stock
Fuel Screw Type: stock
Fuel Screw Setting: 2 I beleive
AP Modified: no
Leak Jet: stock
AP Cover: stock
Exhaust Type: stock
Exhaust Modified: PMB end cap w/ spark arrestor
-Bike is tough to start when cold and bogs coming out of turns. Any suggestions on jetting??
_________________

Year: 2007
Elevation: sea level -200'
Temperature Range: 40-100
Backfire Screen: yes
Air Filter: twin air
Pilot Jet: 48
Main Jet:140
Needle: jd red
Needle Clip Position:5th from top
Fuel Screw Type: flex screw
Fuel Screw Setting: 2.25
AP Modified: yes
Leak Jet: 60
AP Cover: QS2
Exhaust Type: stock
Exhaust Modified: fmf powercore 4

Starts 1st kick hot or cold. No bog ever. Idles perfectly no hanging idle. Works connection tach rpm at idle 1950-2250. Throttle response crisp. Roll on response perfect. Off idle response crisp. No stalling 10yr old kicks over bike with 1 kick and no hassle. Runs flawless.

Year: 2015
Elevation: 500-800
Temperature Range: 60-80
Backfire Screen: stock
Air Filter: stock
Pilot Jet: 45 stock_38
Main Jet: 140 stock
Needle: NMQT stock
Needle Clip Position: 4th from top stock_3rd
Fuel Screw Type: R&D Racing Flex Jet
Fuel Screw Setting: 2
AP Modified: New design n/a
Leak Jet: stock
AP Cover: stock
AP timing: 1/8-1/4 turn sooner
Exhaust Type: stock
Exhaust Modified: n/a

Bike runs great now. the timing on the ap is what really made the deference off idle. I may go one size larger on pilot and main.

Year:2015 CRF150RB
Elevation: 1200ft
Temperature Range: 50-105F
Backfire Screen: no
Air Filter: K&N with modified airbox
Pilot Jet: 40 (stock 38)
Main Jet: 142 (stock 140)
Needle: NHNT (stock NMQT)
Needle Clip Position: 4th position from top
Fuel Screw Type: Tokyo Mods
Fuel Screw Setting: 2 turns
AP Modified: No just played with spring screw adjustment slightly
Leak Jet: 60 (stock was 65)
AP Cover: Quick Shot 2
Exhaust Type: Yoshimura slip on
Exhaust Modified: removed dB killer insert, installed O2 bung

Notes:
Supermoto setup with wideband installed for tuning. OEM -- Start was fine but had lots of carburation issues especially acceleration stumble. Installed a simple Toyo mods kit which looks like it had stock needles for older carbs, smaller leak jet, much bigger slow jet, etc. Acceleration was better but it was very rich at idle once warmed up and difficult to start and tool lean at the top and past 1/2 throttle, still lean stumble when opening throttle too fast. Above is where we ended up, will update if changed.