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Wr426 only starts with choke and hot start

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Well the title says it all. I have no idea how far in or out the idle screw is. I thought I was adjusting the idle screw the whole time but i guess it was just the throttle screw. also is the cable adjustment on the hot start have any thing to do with me pulling it in to start the bike.

Edited by cluelessone

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The bike also dies while giving too much throttle at once. it will bog and then it will rev fine when i give it a very small twist. My current setting on the carb are 170 on the main jet and 50 on the pilot jet and the fuel screw is at 2 turns out

Edited by cluelessone

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Throttle screw? You have an idle screw and a fuel screw (on the bottom of the carb)

Both are adjusted in conjuction with each other. Do a search.

Jetting is all screwed up: 45 pilot, stock needle, 160 main (stock pipe) 170 main (YZ pipe), all other jets stock

Hot start is leaking: service the cable, plunger, and cavity. It must seal tight at the bottom of the cavity. That's why someone put in a 50 pilot, to comensate, but it never works.

Choke plunger is probably also leaking. Service it.

Fuel screw probably has a bad oring, so replace it.

Pilot jet passage (above the pilot) is probably corroded/clogged and needs reaming (fine copper wire and sovent)

Slide plate seal will need replacing, along with the needle jet (not the jet needle) as they wear out pretty fast, and yours is very old.

http://www.dirtrider.com/features/protips/141_0707_keihin_fcr_carb_rebuild/

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Ok so I replaced all seals cleaned the carb and i am now using 162 main jet and 42 Pilot. The needle clip was in the 1st position so I set it to the 4th position.  Now I can get to start first kick with the choke on and theres no bogging. BTW the previous jetting was from the Yamaha dealer's "Tech" recommendation so idk about i had no idea what I was doing so I put what he said to put.  

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OK so now the bike dies as soon as i disengage the choke and it stutters on idle. I have no idea where im at on the idle screw but i turned really far right you know :/. the screw on the bottom is three turns out so I'm guessing that might be causing the rich mixture.

So how many turns would you guys recommend on the fuel screw? I'm not really sure but my guess would be that it is real sensitive to change I had it at 2 1/4 turns out and got the above result then IDK why hey maybe if I turn it out it will do the trick.

Now I have no idea where Im at on the idle screw. how do go back to the original setting? 

Carb was thoroughly cleaned and the diaphram and the other one was replaced

162 main jet

42 pilot jet 

Im at sea level

California weather

clip is on 4th position on needle

tps is off 

fmf powercore 4 exhuast

Edited by cluelessone

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OK so now ive reach a point were i can start the bike first kick and no issues with the idle. Now my last problem to deal with is an oil leak because there is no seal in the decomp assembly.

Do I have to take of the valve cover to install the oil seal (93102-12224-00)??? 

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