Help figuring out carb vent hoses

Bought this 05 crfx 450 a few weeks ago but hadnt had tiime to ride. Was sitting over a year and carb needed cleaning, would start and die so figured jetts clogged. Carb wast too bad but it did smell like old sticky gas. Now it starts and will run okay when on the throttle but wont idle and backfires a bit. There were two vent lines I cant figure out. One comes out the back of the cylinder and T's off to one way down and the other end goes up from T but plugs nowhere. the other comes out of the top of carb on choke side and also seems to plug nowhere. Looking close at both lines they dont appear to have been plugged anywhere as they are very dirty right to the end, both have a slight elbow in the same direction and were "there" when I pulled off the gas tank. Do these just vent to atmosphere?

thanks in advance for help.

Bought this 05 crfx 450 a few weeks ago but hadnt had tiime to ride. Was sitting over a year and carb needed cleaning, would start and die so figured jetts clogged. Carb wast too bad but it did smell like old sticky gas. Now it starts and will run okay when on the throttle but wont idle and backfires a bit. There were two vent lines I cant figure out. One comes out the back of the cylinder and T's off to one way down and the other end goes up from T but plugs nowhere. the other comes out of the top of carb on choke side and also seems to plug nowhere. Looking close at both lines they dont appear to have been plugged anywhere as they are very dirty right to the end, both have a slight elbow in the same direction and were "there" when I pulled off the gas tank. Do these just vent to atmosphere?

thanks in advance for help.

Both hoses are vent hoses. They route as high up as possible, and connect to nothing. They should both have filters added to them.

If it won't idle it is the idle circuit:

- clogged pilot

- stuck hot start

- clogged choke plunger

- fuel screw not adjusted/missing oring and washer

Pull off your seat. On the left side of the frame (just left of the carb) there is a small metal guide. They slide into there. Do not plug into anything. If you need a pic let me know.

Thanks alot just wanted to be sure. now that you mention the fuel screw I did not see the little oring in there, washer was there but no oring, will have to go do that again.

will update later

Gotta have that o-ring. It's either still up inside there, or on the floor somewhere.

Thanks alot just wanted to be sure. now that you mention the fuel screw I did not see the little oring in there, washer was there but no oring, will have to go do that again.

will update later

Yeah, make sure its not up there still. You dont want to double up on it. They do tend to stick.

Going to pull the carb off again in a bit, what is the stock setting for the fuel screw? it was set at 1 1/2 turns out when I last cleaned it. The bike has no baffle in the muffler btw, previious owner says he doesnt have it either, hope it runs ok like that until I find a baffle or another complete muffler.

Going to pull the carb off again in a bit, what is the stock setting for the fuel screw? it was set at 1 1/2 turns out when I last cleaned it. The bike has no baffle in the muffler btw, previious owner says he doesnt have it either, hope it runs ok like that until I find a baffle or another complete muffler.

There is no 'setting'. It's supposed to be within 1 and 2 turns out. If your jetting (pilot) is off, then it will be more or less. You adjust it for highest idle, then drop idle, then re-adjust, etc.

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