YTM200 ERN Jet Screw

[Just-Tri-It]

On the bottom of the carb of the ytm 200 there is a screw next to the bowl that controls a jet. Is it the idle jet and how many turns out is it. I misplaced my manual and was cleaning the carb and want to get it as close as possible.
Thanks

[muthey]

that's the air mix screw "pilot screw" and all machines require it slightly different but according to the manual it is 2 1/2 turns out from seated. I would start with it at 2 and richen or lean it as necessary.

[Just-Tri-It]

Thanks for the info and tip.

[muthey]

your welcome, at least it is easier to pop that carb out and adjust it versus a 350 big bear I was working on last weekend. I literally hate working on anything other than 3 wheelers anymore, they were just built easy access to the things that needed to be adjusted and quite a bit lighter, and I despise working on bikes for that reason.

[Just-Tri-It]

A couple more questions have come up. In the bottom bowl there is a pipe sticking up. Is that a drain or a jet also. When I take the screw out of the side I can blow cleaner through it but not with the screw in, So I'm wondering if it is a clogged jet or just a drain.

2. Also at the end of the carb there are two small holes at the bottom of the circle that look to be vents. Are they both vents are neither. Cleaner doesn't go through them.

[muthey]

the brass pipe is an over flow pipe for when your float height is wrong. the two vent holes should be plugged, on other applications where yamaha or others have used this carb they might have a jet or be a vent. You also have to remember mikuni carbs have been use on all sorts of vehicles including some very old vehicles as well.

[muthey]

on a side note if you look at the pic of your carb bowl the first hole on the top right corner has a jet in it called the starter jet, make sure that is clean and it will start quite a bit easier.

[Just-Tri-It]

Thanks. I usually ride the Z. Had my 200 sitting in shop for several years and it took a few minutes and the tips for the 4 stroke carb to come back to focus in my mind. And thanks for the tip on the top jet. Cleaned the car real good though it was drained before I sit it up. Refreshed the fluids and she starts on a snap with the cord and purrs like a kitten. Gonna get a fresh battery for it and use it for some riding where a two stroke is a little much because of some of the slow ridding. On a side note. I noticed when I turned the top switch over the lights to the 'lights' position it kills the engine. I can't remember off hand why it does that but seems i read about it on a thread once as to why it does it. But I cant remember. It is a blast to ride though.
Thanks

[muthey]

you are talking about the key switch I am guessing , and yes there is a third position on that key that purposely kills the motor and runs the lights directly from the battery where they usually run off the stator.

[Just-Tri-It]

you are talking about the key switch I am guessing , and yes there is a third position on that key that purposely kills the motor and runs the lights directly from the battery where they usually run off the stator.


But Why does it kill the engine when you turn the key to the lights position?? Thanks