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'05 CRF450 bogging ...

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I've gone from a 42 pilot to a 45, added a Quick adjust fuel screw & Boyesen quick shot cover & the thing still bogs out when climbing hills landing off jumps (the bog crashes are starting to hurt)....&%$#@! do I need to do to get the thing from bogging?!!

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Sounds more like clip position than pilot. If you are lean on the clip the bike will definitely give you an over-the-bars hiccup when you wick it.

Go back to the stock pilot and try it one clip richer. You can remove the needle w/ the carb still on the bike if you take off the tank, but you really need a ball-end allen wrench to do this because you can only access the needle cover screw (or whatever) at an angle.

Set the needle on a flat surface w/ the open end of the clip facing down and press down. Put the clip on slot further from the top and reinstall...

Hope this helps.

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Thanks Hick, I'll try that.

The bogging did get better when I went up on the pilot, so I'll try the needle clip next. Could the float level be off? Bike is new (8) hrs old.

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Yeah, the float could be off, not likely but possible. But if it were off enough to result in the bog you are describing you would have other symptoms I would think.

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You need to list your Modifications / State / Alt. / Temp Etc...

----------

CRF450X - HOLLISTER HILLS , CA. 500 – 1500’ 50 – 68 Deg.

BONE STOCK JETTING: 168 MAIN / 45 PIOLT / 2.0 AIR/FUEL

APPLIED SMOG REMOVAL KIT

-----------------------

WITH ALL MODS.

JETTING: 172 MAIN / 45 PILOT / 2.0 AIR/FUEL / STOCK NEEDLE # 5 CLIP POS.

ALL HRC MODS “THE WRENCH” (copy at all Honda dealers)

CRF450R MUFFLER With PRO MOTO END CAP – SPARKY ONLY

TWIN AIR COMPLETE AIR FILTER “KIT”

SCOTT EXTEND AIR FUEL SCREW

SCOTT S/S OIL FILTER

CHANGES MADE SO BIKE WOULD LAST: GNCC RACES / FEW G.P. MX RACES:

CHAIN: DID MX520

PRO TAPER CR “HI-BEND”

TALLON HUBS: FRONT / REAR

ECELL RIMS: FRONT / REAR

BUCANON: 8MM SPOKES FRONT / REAR

FACTORY CONNECTION SUSPENSION

SCOTTS/OHLINS STEERING DAMPNER

ACREBIS HAND GAURDS

BRIGESTONE 201/202

RENTHAL REAR SPROCKET

OVERSIZED WAVE ROTORS : FRONT / REAR

ALL HONDA FLUIDS: HP4 10W/40W ENGINE OIL

HP TRANNY OIL 80W / 85W

Troubleshooting

Bike won’t start after a crash

Pilot too lean

Idle set too high

Improper starting procedure

Bike wants hot start button

Bike runs on or won’t idle down when throttle is chopped

Idle set too high

Air leak intake or engine

Pilot too rich (when bike is hot)

Bike won’t start when cold outside

Pilot jet too lean

Air filter is over-oiled

Motor oil too thick for temperature

Bike sputters/won’t clean out at high RPM

Main jet too rich

Air filter is over-oiled

Spark plug has debris on electrode

Bike coughs and stalls in slow turns

Pilot too lean

Idle set too low

Valves set too tight

Decompressor is set too tight

Bike hesitates or bogs over deep whoops or G-outs

Float level too low

Carb vent tubes blocked

Main jet splash shield not installed

Float level too high, gas is trapped in vent tubes (install T-vents)

Bike starts but won’t take throttle without sputtering

Pilot jet too rich

Water in fuel

Debris in main jet

Bike suddenly starts sputtering/gas flows from vent tubes

Stuck float check valve

Debris in gas or carb

Bike runs hot/feels slow and flat on straights

Main jet is too lean

Fuel octane low, causing detonation

Bike coughs and stalls when you wick open throttle

Needle too lean

Slide cutaway too lean

Pumper circuit blocked or too lean

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FYI ~ Moved the clip down one groove on needle, that helped with bog but seemed too rich until I turned fuel screw in 1 turn (now 1 turn out, pilot=45); still a little bog when landing from steep uphill jumps; I think if I change the leak jet from 55 to 52, that should remove it.

Stock except Boyesen Quick shot, screen removed from air filter cage, state=CT, alt.=sea level, temp.=75

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FYI ~ Moved the clip down one groove on needle, that helped with bog but seemed too rich until I turned fuel screw in 1 turn (now 1 turn out, pilot=45); still a little bog when landing from steep uphill jumps; I think if I change the leak jet from 55 to 52, that should remove it.

Stock except Boyesen Quick shot, screen removed from air filter cage, state=CT, alt.=sea level, temp.=75

If you find a straight and relatively flat road you can try to isolate the different carb circuits and eliminate the effect of the AP by holding a constant throttle position. After a few passes in a tall gear (4th or 5th) you should be able to "feel" where the needle comes on to the taper (the timing of this relative to throttle is what changing clip position does).

Another trick to isolate the pilot circuit is very low throttle runs, and you can tune your idle mix (in part) by trying to eliminate any surging or popping at different rpms w/ the throttle off (get up to speed in 5th, then chop the throttle and downshift).

In my experience it is easier to first try and sort the jetting this way and THEN tune the AP.

Hope this helps.

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