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1985BigRed250ES
07-25-2009, 10:39 PM
I have a 1986 Yamaha YFM 225. I took the carb off today to clean it, got it clean and put it back together. the air/fuel mixture is 2 1/2 turns out. the throttle needle is on the middle clip. It will start easily, idles smooth and it will rev smooth until I put it into gear. when I put it into gear and give it gas it falls on its face. what could be the problem guys?

1985BigRed250ES
07-26-2009, 03:06 PM
ok guys, I moved the throttle needle from the 3rd or middle clip to the fourth clip on the needle. it runs alot better. it will idle smooth and rev smooth while in neutral. when in gear it will only run with the choke on 1/2 way. with the choke on 1/2 way, it will run good and is responsive to the throttle, but does not idle very well with the choke on. when I took the jets out of the carb, I ran a piece of wire through the little holes that go across the jets, but when I tried to run the piece of wire through the hole that goes length wise through the jet, the wire will go in, but not all the way through. shouldn't the wire go all the way through the jet length wise?? help me out here guys.

Jordan

MonroeMike
07-26-2009, 05:46 PM
Yes, it should go all the way through. It tapers down, I burned the paper off a garbage bag tie and (very carefully) used the wire from that and carb cleaner. Probably not the best way to do it, but I had it soaking for days and it was still clogged. It was packed solid with green gook.

FWIW, my book say fourth groove from the top for the clip and 1 - 1/4 to 2 - 1/4 turns out for the idle mixture screw.

1985BigRed250ES
07-26-2009, 07:14 PM
MonroeMike, thanks for the help. I have been trying to get this atv running for a year. I will take the carb apart tomorrow and let it along with the jets soak for a couple of days. I have a gallon of carb cleaner that it can soak in. I have heard that if left for too long, the carb cleaner will eat the carb up, is this true?

Thanks

Jordan

1985BigRed250ES
07-26-2009, 07:19 PM
do you have a downloadable copy of that book? Or do you know where I can get one? If I have to go buy one, what is the best to get? I have a clymer manual for my atc 110 that doesnt seem very detailed.

Thanks

MonroeMike
07-26-2009, 07:59 PM
I just had the jet sitting in the carb cleaner, not the whole thing. I cleaned the body with a toothbrush. I know Evaporust is safe to soak carbs in, but I never tried it. Not sure about the cleaner you have.

I just have the quick data for the YFM225, no manual. When I get a chance, I'll scan it.

1985BigRed250ES
07-26-2009, 08:21 PM
thanks, I appreciate it.

1985BigRed250ES
07-29-2009, 08:46 PM
ok. I got it to run a lot better now. but I think there is something wrong with the float. It will idle for about two mins and then slowly idle down until it dies. It will start right back up, and will not idle too well until I open the carb drain bowl screw to let some of the gas out of the carb while idling and it will idle all day. I think the float height is set wrong. are they even adjustable? If not I will have to get a new float from the dealer. Is there anyone that would happen to have a yfm225 carb laying around?? thanks

Jordan

MonroeMike
07-29-2009, 09:28 PM
Did you put the floats in with the round sides up?

I doubt if the floats are bad, you can try them in a bucket of gas though. Mine aren't hollow on my 225, they are that black solid stuff.

Set the float assembly on a flat suface, make sure both the floats are even, carefully bend them if they are not.

Adjust your float the way described in this post.

http://www.3wheelerworldforums.com/showpost.php?p=575273&postcount=4

1985BigRed250ES
07-30-2009, 09:00 PM
that sounds easy. I will have to wait until it quits raining here to do anything else to the atv. it has been raining for the last two days on and off and has dumped atleast 1" during each rainfall.

1985BigRed250ES
08-03-2009, 09:52 PM
I got it to run nearly great now. it will rev smoth idle smooth until the carb loads up on it. If I keep the idle on the high side it idles good. It has some hesitation/missing a little bit. If I tunr the choke on like a 1/4 It runs excellent, so what do you think it might be? a jet still clogged? choke needs adjusting? how do you adjust the choke? bad float maybe? I would like to rebuild the carb but they do not make a rebuild kit for this carb. I know If it had new jets and a float in it, I could probably get the carb right, but I will have to wait if thats the case because money it tight right now.

MonroeMike
08-03-2009, 11:50 PM
Here's two good threads that should help.

http://www.3wheelerworldforums.com/showthread.php?t=23819

http://www.3wheelerworldforums.com/showthread.php?t=55086

1985BigRed250ES
08-05-2009, 09:14 PM
mike, I appreciate it man. I will take another stab at it this weekend after, I help put an old suzuki quadrunner 250 4x4 together. it shouldnt take long though, just a top end.