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09 yz250f won't start with boyesin hot start

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I've tryed searching but I'm using my iPhone and it's not letting me do a search. Not realy sure why. Its only letting type one letter then going blank.

So my 09 yz250f runs great but just won't start with the hotstart or with out the hot start once it's warmed out. It's got a rocky mountion slip on on it and a boyesin quick start.

I'm not sure on the jetting yet. Because I just bought it and I've only had it out twice. It will fire first kick when cold and idels just fine. I have tryed turning the pilot jet both in and out in 1/4 turn increments as far a 1 full turn with no noticeable improvement.

If I let is sit for a few min it tends to fire up after just 3 or so kicks. Kinda depends on how long I wait. The longer the quicker it fires.

I plan on checking my jetting after work.

What might be the cooperate with out knowing the jetting?

Thx. Sure this has been asked before but I can't get the search to work with my phone and didn't find anything helpful with google.

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The Boysen hot start is carb jewelery and does next to nothing other than cost money. If you have the OEM partsd, put them on.

Fuel screw settings in the 'book' are recommended starting points. Every bike is different, as is the temp and altitude. Set the screw according to this method. Do it with the bike fully heated up.

Gently turn the screw all the way in. Now back it out two turns. Start the bike and fully warm it up, go for a 10 minute ride. Set the idle to speed to 1,500~1,800 RPM as best you can (I know, without a tach this is tough, just set it to were it idles relatively smoothly). Once warmed, slow the idle to the lowest possible speed.

*** When turning the fuel screw, keep an accurate 'count' of the amount you are turning it and record it in case you have to reset it for some reason. Makes life easier when you can just set it from notes Vs. going through the procedure again.***

Turn the screw in until the idle becomes rough or the bike stalls.

if it stalled, open the screw about 1/4 more turn. Restart it and slowly screw it in till you can just perceive a change.

If the screw can be turned all the way in and the bike still idles perfectly and does not stall, then you need to go down a size in pilot jet.

Now very slowly, open the fuel screw till the idle is smooth. Blip the throttle, let the bike return to an idle, wait say ten seconds. Confirm it is the same smooth idle.

If the screw has to be opened more than 3 turns to get a smooth idle, you need to go up a size in pilot jet.

If you find it does not stall with the larger jet but has to be open more than three turns with the smaller pilot jet, put the larger one in and set the fuel screw at 1/2 turn.

If the idle speed increased, adjust the idle speed knob to return the bike to a real slow idle speed. You must then re-visit the fuel screw. Keep doing this till the fuel screw is opened just enough to provide a nice steady idle at the lowest possible RPM. Once this is done, increase the idle speed to the normal one for your bike, typically about 1,800 rpm, but go by the spec in your manual.

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Well decided to adjust the pilot jet with the boyesen quick start first simple because the bike didn't come with the stock boll for the carb. I set the pilot to 2 turns out. The boyesen guide says that should be a #70 witch is stock. I also adjusted the idle alittle. I turned it all the way in till the bike stalled and then turned it out till it idled good. Came to a 1/2 turn out from where it was when it stalled.

Know the bike fires first kick when cold and after warmed up it fires up fist kick even without the hot start.

Know I haven't had a chance to ride it on a track yet since the adjustments so not sure if that will require the hot start or not. But seams to be working much better. I did let the bike get pretty warm during the adjustments BTW.

Funny thing is the piolet adjustment knob was 2 1/2 turns out before when I was having truble and I tryed turning it and and out with no change. And know its working and its 2 turns out. So the only real diff if the idle.

Your alls thoughts?

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Yes i believe your are getting the quick start adjustment screw confused with the actual fuel screw on the carb, The boyesen screw is essentially an adjustable leak jet, The fuel screw helps fine tune the pilot circuit. And is a brass screw located up in the center of the carb on the bottom side. set that to 2 1/2 turns as a base.

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Hum I thought the boyesen quick start done away with the pilot jet. That's how the paper that was with it made it sound anyways. So it actuly does away with the leak jet.

Yah I know the idea screw is the One that's a pain to get to. I havent messed with it yet. Didn't really have much time to fool with it. So I just checked the idle setting and what I though was the pilot jet adjustment knob (the boyesen knob) but guess it was actully the leak jet. I'm off work tomarrow And it's pro going to rain so I might have to check all the jetting and then adjust the fuel screw and what not.

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The hype about this 'product' is incredible. It does NOTHING to help starting.

Idle speed is the knob on the side of the carb. Fuel screw is on the bottom. You'd be wise to get an extended on made of brass or stainless steel. Do noit get a alloy one.

You can only properly set the fuel screw on a bike that is fully heated up. Not something you can do in a garage.

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Ok just bubble checked the boyesen guide and what I have wrote down and it was the leak jet that I adjusted and not the pilot jet at all. Not sure why I was thinking it was the pilot jet.

So any ways, I did set the Leak jet to the stock jet (#70) so two turns out with the boyesen.

I didn't get time to ride it though do to when I came home I had a mess in the back yard thanks to crazy winds.

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