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Has this ever happened to you? - Cutting out with choke on

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.... when you start your bike, you put the choke on and you're warming it up.... Then you get on the bike (kept in neutral), and you hold the front brake on to test it... then push the bike down on the front folks....... Then the engine cuts out?

In doing so the gas in the tank moves back ( when I lift up on the handle bars a little ) and then forward (when I push down on the handle bars and compress the forks). The the engine cuts out!!!

Is this a normal thing?

It does NOT happen when:

1. the choke is fully off and when and engine is warmed up ready to go.

It DOES happen when:

1. the choke is fully on when I just start up and I push down on the front forks.

2. the choke is on half way, but seems to do it less when I push the bike forward and stop immediately

thank you in advance!

Cheers.

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does it do it while riding? does it cut out while idling?

if it only cuts out when the bike moves then i would think it's an electrical problem. but if it does it otherwise it may be that the spark plug gap is to narrow, or simply your valves are out of spec or idle set to low.

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Hi there and thank you for your reply!!

does it do it while riding? does it cut out while idling?

It does not cut out while riding or when the choke is all the way off and the bike is warmed up

It does not cut out while idling.

It cuts out when I move the bike front and quickly stop it, only when the choke is open full way or half way.

Thank you.

any other thoughts?

Cheers.

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Ok, my guess is that stock it is jetted too lean. Try going up a size on your pilot and I suspect your probs will go away.

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slack: Thank you for your reply!!

Try going up a size on your pilot and I suspect your probs will go away.

So, you mean just to adjust the idle screw to be a little richer??? Is that correct?

Thank you again for your reply, I really appreciate it, as I'm just learning.

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slack: Thank you for your reply!!

So, you mean just to adjust the idle screw to be a little richer??? Is that correct?

Thank you again for your reply, I really appreciate it, as I'm just learning.

I assume you have a sealed carb(aka plugged air screw), so the idle screw will only ratchet up your rpms, but it may solve your flame out. I don't think you'll get there solely by turning the idle screw. The air screw is usually capped off with a brass plug that can be drilled out. By changing/richening the pilot jet (it's a hard part, screwed inside the carb) I think ultimately you'll have the elegant solution to your problem. Then again, if you're able to scratch your itch with a couple turns of a screw :D

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Ok... I've checked both changes - turning the idle speed needle leaner and testing... then richer and testing.... no change.

Is this something I should worry about?

Does this happy any of your non-fuel injected bikes, guys?

Does anyone else get on their bike while it is warming up and test the front brakes like this, rolling ahead a few inches and then jamming the front brake, looking for front fork compression .... then seeing the engine cut out (with the choke on full or half way?)?

thanks

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The air screw is usually capped off with a brass plug that can be drilled out. By changing/richening the pilot jet (it's a hard part, screwed inside the carb) I think ultimately you'll have the elegant solution to your problem. Then again, if you're able to scratch your itch with a couple turns of a screw

Thanks for your reply. Things like that are outside of my range of knowledge on bikes/engines at the moment.

Just wondering if this is common for the XT250 or bikes in general that are choked?

The problem does not arise when the choke is off or I'm riding the bike, or riding and then coming to a quick stop at a stop sign/red light for example.... only when the choke is on full or half way.

thanks

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Must be fuel sloshing around in the bowl, not the tank. Probably flooding through the enrichener. (Not really a choke)

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Must be fuel sloshing around in the bowl, not the tank. Probably flooding through the enrichener. (Not really a choke)

Thank you for your reply!

So, the bowl, is that in the fuel cock area or down below, in the carb someplace? (sorry, I'm new).

Do you think this is a normal then?

thank you

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Bottom of the carb. It's the resevoir the carb draws fuel from and has float valve on the supply from the tank that keeps the level relatively constant.

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Bottom of the carb. It's the resevoir the carb draws fuel from and has float valve on the supply from the tank that keeps the level relatively constant.

Is it normal to see this on a bike that is non-fuel injected?

thank you.

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Most bikes will cut out all the time when ridden with the choke on. That is why I don't ride them that way!. The "choke" enrichens the slow or pilot circuit to ease cold starting. The motorcycle is not meant to be operated in this condition. I have had past multicylinder street bikes that would not even run above idle with the choke left in the on position.

As a rule of thumb, when starting the bike with the choke, I do not ride it until the engine will idle smoothly with the choke off and it up to a more proper operating temperature. This helps the motor in that the internals are up to temp and that warm oil is now circulating properly through the motor before the motor is put under a "load."

Your engine will live a much longer and happier life this way!

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east: Just note, I've not ridden with the choke on, at all.

the issue I see is when I'm starting the bike, it is not going, it is in neutral. I get on the bike push the bike only 1-3inches and grab the front brake ( to test the front brake). The front forks go down as I grab the front brake and then the bike cuts out!

Again, I"m NOT riding the bike with the choke on.

Do you know why a bike would cut out when moved forward only a few inches and then suddenly stopped, when the choke is on fully or half way?

My bike does NOT cut out when the choke if off and I move it a few inches and grab the front brake.

The issues seems to be in the slight movement forward and sudden stop that cuts the engine every time ( despite the idle screw setting ). I hear the fuel in the tank being sloshed around... perhaps it has something to do with that??

thoughts/comments, welcome.

thank you

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What people are telling you is don't worry about it if the bike runs ok with the choke off. Maybe it would happen to other bikes but no one has done what you do to so they haven't noticed it or if it did they said ok it's warmed up enough and time to shut off the choke.

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What people are telling you is don't worry about it if the bike runs ok with the choke off. Maybe it would happen to other bikes but no one has done what you do to so they haven't noticed it or if it did they said ok it's warmed up enough and time to shut off the choke.

Ok, thank you.

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