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I just went from a stock air filter to a No Toil Dual stage filter and my bike runs, but
Seems to stall upon quick throttle blips and just does not runs as well. What adjustments
Do I need to do.

Other suggestions welcome.

Thanks

Start with Fuel Screw , turn it in till just seated and count the turns , you should be between 1 1/4 -2 3/4 turns out , if it wont run better within that range then you need to re-jet , larger main , maybe lower the clip on the needle to 4th position , that should get you started in the right direction

Jim is on the money.
Fuel screw should get you there.

If I remember correctly I have a 168 main and a 48 pilot. I will adjust fuel screw and see what happends.

Thanks for you help.

What is your elevation (or the elevation you normally ride)

This is the guide for jetting

Jetting Guide for Main Jet:(pilot 45)CRF450R/X

Sea level...165
2000 ft.......162
4000 ft.......160
6000 ft.......158
8000 ft.......155


Temperature/Elevation:
One main jet size (up/down) for every 2,000 feet or 25 degrees in temp.

JimDirt wrote:What is your elevation (or the elevation you normally ride)

This is the guide for jetting

Jetting Guide for Main Jet:(pilot 45)CRF450R/X

Sea level...165
2000 ft.......162
4000 ft.......160
6000 ft.......158
8000 ft.......155


Temperature/Elevation:
One main jet size (up/down) for every 2,000 feet or 25 degrees in temp.

Thanks for the information. I'm in California
so the areas I ride in range from 30 Sacramento
to Forresthill 3225.

Once it cools down, I'm going to try the fuel screw adjustment.

Thanks again

Ok, Where is the fuel screw? Anyone have a picture or location?

Thanks

Bottom of the carb at the front of the bowl

You need one of these , it will make life easier so you dont have to loosen the carb and twist it sideways to adjust the fuel mixture

http://www.crfsonly.com/catalog/product ... ts_id/2792

JimDirt wrote:Bottom of the carb at the front of the bowl

You need one of these , it will make life easier so you dont have to loosen the carb and twist it sideways to adjust the fuel mixture

http://www.crfsonly.com/catalog/product ... ts_id/2792

Thank you

External fuel screw adjuster is a must. If you have big hands make sure you get one that has a flex neck and can be mounted further to the outside of the carb like the link that Jim Dirt gave. There are others that are just a big finger screw. They work well too, just not as simple to get at.

I purchase the oversized fuel screw and adjusted the fuel screw (Mr smiths directions) and still have everything from quick throttle flame outs, or bogs. It’s odd I can do 6 quick throttle twists and on the 7th it will flame out or die. It back fires sometimes and it just doesn’t run well. I went back to a stock air filter and still have the same problem. The Honda service Advisor told me to go to a 50 or 55 leak jet and go down in the pilot. I guess it’s just a coincidence that all this happened after changing the air filter, but It sure got me baffled.

I have a question , are you oiling the crap out of that No-Toil filter ?? , if you are your starving it for air and that would make it bog,pop,stall

With a #45 pilot and a main in the area of 160 - 165 and the fuel screw between 1 1/4 - 2 3/4 , the bike should run fine

Rule out that the squirt is not hitting the slide when blipping the throttle (engine off , airbox off/ subframe up) and look to see down the throat of the carb if it just barely misses the slide , if the stream hits you need to adjust the AP timing , also try taking a small O-Ring and putting it around the AP screw and the stop

I thought there was a post here , but this is the only one i could find that has pictures to show you what to do , but this might help stop the bog

Also , if your rev-ving it on the stand it will bog /pop/stall sometimes , so make sure it runs fine under load , on the stand means nothing (sorry Ken for the link to that "other" site)

http://www.thumpertalk.com/topic/539540 ... or-an-fcr/

JimDirt wrote:I have a question , are you oiling the crap out of that No-Toil filter ?? , if you are your starving it for air and that would make it bog,pop,stall

With a #45 pilot and a main in the area of 160 - 165 and the fuel screw between 1 1/4 - 2 3/4 , the bike should run fine

Rule out that the squirt is not hitting the slide when blipping the throttle (engine off , airbox off/ subframe up) and look to see down the throat of the carb if it just barely misses the slide , if the stream hits you need to adjust the AP timing , also try taking a small O-Ring and putting it around the AP screw and the stop

I thought there was a post here , but this is the only one i could find that has pictures to show you what to do , but this might help stop the bog

Also , if your rev-ving it on the stand it will bog /pop/stall sometimes , so make sure it runs fine under load , on the stand means nothing (sorry Ken for the link to that "other" site)

http://www.thumpertalk.com/topic/539540 ... or-an-fcr/

No I did not over oil the filter. I even went
back to a stock pre-oiled filter to make sure.

I tested the bike under load with same results.

I will have to look up ap timing.

Thanks for the suggestions.

What year is your 450? And what have you done as far as MOD's?
Your pilot is a little too large. Try a 45 or even a 42.
Adjust the fuel screw this way and the bike will tell you what it wants for a pilot,

Setting the fuel screw mixture-
Try adjusting with the motor fully hot, and turning the fuel screw inwards until the idle slows or runs rough, then turn outwards 1 1/4 turns from this position. For example, if the idle slows or runs rough at 1/2 turn, then set the fuel screw to 1 3/4 turns out (1/2 + 1 1/4 = 1 3/4).
See- http://www.pbase.com/jdjetting1/image/82894252 to understand how the fuel screw can affect the idle speed and air/fuel mixture at idle. The target range for the air/fuel mixture is near 12.5 to 13:1 at idle.

Everything I've read to this point I agree with. You mentioned one thing that raised my ears a little. You said that you can rev is 6 times without issue then the 7th it would flame out.
While you have the bowl open. Make sure that your floats are not stuck creating a false lean condition.