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Hey,

I have read post after post about jetting setups and cannot decide on which is the best for me.. I'm no expert so i'm basing what I end up using on (hopefully) the experts on these forums

I have an 08 crf450x, cut airbox (top & side), cut off exhaust baffle, twinair filter. I have a 165 & 170 main jet sitting there, i have installed an R&D fuel screw, and i have the NCVS 16233-MEN-671 neddle ready to go, but also unsure of which position to put it in.

I ride from Sealevel to approx 2000ft.
Live in australia, temps around 10-25 celcius.

Hopefully this is enough information.
Just need to decide which mainjet to use, and which needle position..

Thanks heaps in advance

Ahhh...Mr. Anderson...we meet again.

The NCVS needle with the clip on the 4th slot from the top.

The 170 main.

The fuel screw set at 2 turns out to start with. Adjust from there.

Hey,

Thanks for that.

I havent put the needle in yet.. So im using a stock needle, stock posistion, with a 165 main jet...
And i have bad bog in 2nd from low revs, that wasnt there b4 i changed to a 165 main to modded my airbox.

I'm going to install the new needle tonight and put the 170 main jet in... you think this will fix that bog?

Thank

Neo

Your off idle bog has nothing to do with the main jet. The main jet doesn't come into play until 1/2 throttle.

The off idle bog is caused by an issue in the transition zone between the pilot jet and the needle. The AP is designed to take up the slack in this zone.

Running the NCVS needle in the 4th clip will richen up the needle side of the equation. You may have to open up the fuel screw a bit to richen the pilot side of the equation.

2 to 2 1/2 turns out from full in.

once again, thx for the info.

One question, might be a stupid one, but when i took the float bowl off, there was a white cap thing in there, with holes where the main jet. etc. is.. I forgot to put that back in.. do i need it? whats it for?

Also what causes bog? too much fuel not enough fuel?
Or not getting into the engine quick enough when you twist the throttle quickly?
Just trying to understand how it all works, new to all this?

Thx heaps, you've been a great help

Neo

bump bump... still chasin some answers
hehe.. thx