05 250 high idle when cold

[Smoking 2's]

Recently picked my son up a 250, with choke on and cold especially outside this thing rev's to the moon. Choke immediately off and it's fine. I've done the ether tests and no leaks. Is this normal for these? I've seen a few articles on it but haven't seen a cure other than to hurry and turn off choke lol

48 pilot 

[RidingWithStyle]

I have a 48 pilot no leaks as well and noticed my idle was a tad higher than normal once it got colder out as well. I just turned it down and rode. I never have to use the choke on mine unless its sat for a while.

[Smoking 2's]

7 minutes ago, RidingWithStyle said:

I have a 48 pilot no leaks as well and noticed my idle was a tad higher than normal once it got colder out as well. I just turned it down and rode. I never have to use the choke on mine unless its sat for a while.

Generally if no choke is needed the pilot is to small, and we haven't tried starting without choke to see what it does

[RidingWithStyle]

Generally if no choke is needed the pilot is to small, and we haven't tried starting without choke to see what it does

I never used choke during the summer and it would generally fire 1st kick. Sometimes i have to use it though. I always turn the throttle 2 blips before kicking and it fires right up. If it starts to die off i pull choke up and let it sit for a few seconds.

[Smoking 2's]

10 minutes ago, RidingWithStyle said:

I never used choke during the summer and it would generally fire 1st kick. Sometimes i have to use it though. I always turn the throttle 2 blips before kicking and it fires right up. If it starts to die off i pull choke up and let it sit for a few seconds.

I'll have my son give your way a try next time til we get it figured out.

When choke comes on while cold it screams, my first thought was cold seize "yikes".

While cold, choke off and it idles normal so perhaps choke ain't needed but it shouldn't be that way or at least hasn't on any other older yz I had or have.

 

 

[Shooter88]

My 250 has always revved high when starting with the choke on.  It worried me too at first but after doing a little research, it seems to be a common thing with the YZ250. I've read that if you tilt the bike all the way briefly to one side then back up again prior to starting it will help, but have never tried it myself. I just learned to reach down real quick and shut it off. It's never resulted in any engine damage.

Edited November 19, 2018 by Shooter88

[Smoking 2's]

Just now, Shooter88 said:

My 250 has always revved high when starting with the choke on. I've read that if you tilt the bike all the way briefly to one side then back up again it will help, but have never tried it myself. I just learned to reach down real quick and shut it off. 

Lol yeah I was quick when my son fired it up ?

[218]

When your bike revs higher with the choke on it usually means you pilot circuit is lean. It leans out a lot when it gets cold.

[Kinger317]

Check the float height. fuel level is critical on these bikes and affects a lot more than just fouled plugs.

[Smoking 2's]

4 minutes ago, Kinger317 said:

Check the float height. fuel level is critical on these bikes and affects a lot more than just fouled plugs.

That's one thing I haven't checked yet. I pulled the plug after his first 30 min and seems to run clean. I going to pick up a couple sizes bigger pilots to try out and see what happens

[Kinger317]

That's one thing I haven't checked yet. I pulled the plug after his first 30 min and seems to run clean. I going to pick up a couple sizes bigger pilots to try out and see what happens

One thing at a time or you could be fixing one thing and inviting another not so great situation.

[Smoking 2's]

8 minutes ago, Kinger317 said:

One thing at a time or you could be fixing one thing and inviting another not so great situation.

Float height is at 6.3 mm

[TwoFiddyYZ]

My bike revs like hell when cold with choke also. I just use the kill switch to tame rpms.

[Smoking 2's]

Glad there's temporary fixes to get around it but I'll have to find a solution otherwise I'll go nuts thinking about it ?

[Smoking 2's]

2 hours ago, TwoFiddyYZ said:

My bike revs like hell when cold with choke also. I just use the kill switch to tame rpms.

I did find this from some online magazine, it's what they found, as said by them to fix the 05 and make it the best it can be. I wish I had the link cause they had multiple years and jetting for all of them. The thing that stood out was they use a #50 pilot instead of #48.

[Smoking 2's]

1 minute ago, Smoking 2's said:

I did find this from some online magazine, it's what they found, as said by them to fix the 05 and make it the best it can be. I wish I had the link cause they had multiple years and jetting for all of them. The thing that stood out was they use a #50 pilot instead of #48.

Not sure how text got in the first picture lol

Whether it's correct or accurate I have no ideal, just a thought

[Kinger317]

Float height is at 6.3 mm

Not bad, I like mine at 7.5 but that's pretty close.

[Kinger317]

Not sure how text got in the first picture lol
Whether it's correct or accurate I have no ideal, just a thought

Be careful what you read!!!

[RidingWithStyle]

I run 48P/175M in mine. I still have to richen it up some because on long uphills it slightly surges and when you get on it and kinda coast into corners it surges. Going to turn my A/S out to 2 turns out and see what happens.

[Kinger317]

I have experienced that takeoff high idle cold choke start before and it $uc&s. It went away and best I could figure was float adjustment but not 100% sure, changed too much too quickly ha ha. Nothing I have now does it fortunately but a lot of us have been there[emoji35]