need some info about my carb .

[bad-boy-416]

heres what i have - stock bore , dmc exhaust,stage one hotcam,and no air box lid with a 39fcr

50 pilot
175 main
fuel screw 1 turn out



how do you know when the screw in the back of the carb is perfect ?

need some feed back

[ewalker302]

Just play with it.

Lots of factors such as temp & elevation determine what your settings should be.

How is the bike running?
does it bog or feel ike its not revving like it should be, when you get back hard on the gas (rich)
does it backfire any on decel, or seem to run too hot (lean)

the best way I have found to fine tune is to
tighten your fuel screw in 1/2 turn if its rich
or loosen it 1/2 turn if lean
when you get it the best you can that way
try turning the screw 1/4 turn in both directions
until it runs the best.
If you still cant get it right you need to go up or down on your main accordingly.

you should also try moving the E clip on the needle according to your feelings of rich or lean at medium throttle.

A stock machine that is perfectly tuned can beat a lightly modded bike thats not tuned right anyday.

I found out quick that running too rich on the fuel screw, even if the jet is correct will hamper performance.

Long post, but I recently had to go through the same thing on my bike & I loved the power I gained just by fine tuning for a while.

Also just my $.02 & I may be way off but it seems that running a 50 pilot w/ screw 1 turn out may be giving you problems. I would also try dropping down on the pilot to allow you to open up the fuel screwfor idling & putting around. I think stock pos is like 2 1/2 or 3 turns out, so you may be able to get better low throttle response w/a smaller pilot & a more open screw.

Good luck
:bandit:

[luvmyex]

very good info ewalker:eek2: Im about the same as he is.When i had the 416motor and a hotcam2,open airbox,Colby had told me to try a 165m & 52 pilot. Now i i have the stock air box but the lidsis on the front two clips for a little more air,and a stock bore and cam.Just the 39fcr.K&N, W/B 12 disc,and a ground stock pipe.Do i need to drop down in the jets now?I just got it togeather and dont even have a swingarm on it but it has a little popping and sputtering when i hit the gas.

[Narly R]

Man ewalker302 Im glad ur here you give some good information!:)

[ewalker302]

Thanks guys I have gotten so much good advice here, the mods seem to get rid of a lot of the crap usually found on these types o sites, so I just like to try to help out.

The best way I have found to test main jets is to run hard down a gravel road or trail in 4th or 5th gear, then let off the throttle all the way for maybe 1/2 a second when U slow down to hit a turn.

Then slam the gas to get through the turn, if you are too rich the engine wont pick up revs like it should.
when the main is jetted right it should rip when you stomp back on the gas.

This is how I tuned in my dynojet kit & it was pretty easy.

I dont know about your pilot, my bike is still pretty stock, & it seems to idle & run good w/ the stocker.

Good luck.

:bandit: