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Yz250F won’t start

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I bought a YZ250F yesterday and the previous owner said apparently it runs but they weren’t strong enough to kick it. I couldn’t kick while there so I took their word for it and bought it. I’ve been trying to get it to fire all day today, there are 2 chokes and I’m unsure if the air mixture is correct, so would be nice to know what I should do, it’s hard to adjust the air screw when the bike won’t even run. I noticed the spark is kinda low, I don’t know if it’s normally supposed to be like that or not. I can see a blue spark but it is very small and crappy, I’ve had thumpstars that generated stronger spark, I changed the plug it’s still the same, so maybe could be an electrical problem, the only ground connection I could find was for the ignition lead which I filed down to bare metal so I’m pretty sure that connection is good. Anything else I’m missing? It’s very hard to kick and I can feel the compression out of the exhaust so I don’t think compression is the issue.Just wanna know what I should do, haven’t owned a yz before so I could be not using the choke right or something. Thanks 

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I think it's a little odd they said they couldn't kick it over.

Did they mean literally hard to kick over, or hard to kick over as in it won't start?

Is the motor difficult to rotate 360 degrees, or just firm during the compression stroke.

It shouldn't be stiff/drag/tight during the intake and exhaust strokes.

I would also post this in the relevant forum, you may get better results.

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What year is it? 

Sounds like you're forgetting to use the manual decomp lever to help it over top dead center. The choke is the black knob on the left side of the carb, and the red is the hot start knob. 

 

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8 hours ago, WALKINGWOUNDED said:

I think it's a little odd they said they couldn't kick it over.

Did they mean literally hard to kick over, or hard to kick over as in it won't start?

Is the motor difficult to rotate 360 degrees, or just firm during the compression stroke.

It shouldn't be stiff/drag/tight during the intake and exhaust strokes.

I would also post this in the relevant forum, you may get better results.

The people I bought it off said they bought it for their 15 year old nephew and he wasn’t strong enough, when I went to look at it I didn’t know the proper technique to kick it so I wasnt able to kick it either, once I got home i searched how to do it and I was able to kick it, it feels right, it’s hard when it’s on the compression stroke but once it gets through then it’s easy all the way down. I think they might be lying about the bike running though because the woman’s story didn’t match with what I found on the bike once I got it home, she said a week ago it was running perfectly and then third nephew wasn’t able to start it anymore and he said he wanted a smaller bike after that. I realised when buying it there was no petrol in the tank so I asked if there’s any leaks and she said no, when I filled it up at home  the carby was leaking and there’s a crack in the fuel tank which petrol was flowing from pretty fast, I don’t think they would’ve been able to ride it like this. Fishy 🤔

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4 hours ago, Swappa said:

What year is it? 

Sounds like you're forgetting to use the manual decomp lever to help it over top dead center. The choke is the black knob on the left side of the carb, and the red is the hot start knob. 

 

Yeah I’ve been using the decomp to prime the engine, I don’t know if that works or not, just thought that by kicking it a couple times with decomp I can get fuel into the cylinder. Also I had the black choke pulled out and red one pushed in, is that right? 

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5 hours ago, Swappa said:

What year is it? 

Sounds like you're forgetting to use the manual decomp lever to help it over top dead center. The choke is the black knob on the left side of the carb, and the red is the hot start knob. 

 

Sorry also it’s a 2001 model 

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1 hour ago, Allooushh said:

Yeah I’ve been using the decomp to prime the engine, I don’t know if that works or not, just thought that by kicking it a couple times with decomp I can get fuel into the cylinder. Also I had the black choke pulled out and red one pushed in, is that right? 

The decomp lever helps to relieve engine compression as the piston goes over top dead center. Push the kickstart until you feel max resistance, pull and hold the decomp lever in and push the kickstart approx. 1/3rd way through it's stroke. Release the lever and with the black knob pulled out , and the red one pushed in,  you're ready to give the bike a decent kick with closed throttle and it should start. 
The carb on these bikes has an accelerator pump and the only way to 'prime' the motor is to twist the throttle. On or off, the bike will prime the motor as you twist the throttle. 

From dead cold, we used to prime the bike with a couple of pumps of the throttle before going through the procedure. 

 

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2 hours ago, Swappa said:

The decomp lever helps to relieve engine compression as the piston goes over top dead center. Push the kickstart until you feel max resistance, pull and hold the decomp lever in and push the kickstart approx. 1/3rd way through it's stroke. Release the lever and with the black knob pulled out , and the red one pushed in,  you're ready to give the bike a decent kick with closed throttle and it should start. 
The carb on these bikes has an accelerator pump and the only way to 'prime' the motor is to twist the throttle. On or off, the bike will prime the motor as you twist the throttle. 

From dead cold, we used to prime the bike with a couple of pumps of the throttle before going through the procedure. 

 

Sweet will try this once I put the bike back together. 

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took the harness off and found these wires have been chopped, they connect to that thing that’s behind the shifter, don’t know what it does, don’t know what they are supposed to connect to on the other side aswell. Anyone know this?

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Ya that will be the neutral switch you dont need it really for anything mine has the wires pulled rite out of it and has no effect on it

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