23 yz250f cranks over and over but won’t start

[Jc32]

My brand new 250f won’t start. It cranks but won’t fire up. I’ve checked the plug and tried everything I know but can’t get it to start. Brand new battery 

[mlatour]

1st post, Welcome to TT Forums Jc32!

 

First to put things into context,

-since you've got the bike, have you been able to start it at least once? (is it fresh out of the dealership)

-is the bike stored in cold ambient temps?  (say below 45°F)

-did you check the plug after a failed starting attempt?  (was it getting fuel, sparking?)

 

Edited March 27, 2023 by mlatour

[Piney Woods]

Why not call the dealer before you screw something up? Absolutely sure it has gas?

Edited March 27, 2023 by Piney Woods

[Jc32]

Yes it’s brand new 3 weeks old. And it has never fired up as quick as I think a brand new bike would but yes it was starting. I took it back to dealership last week because battery was no good. I got a new battery from Rocky Mountain and it fired up.  It then sat 2 days and will now only crank till the battery dies. I have the battery on a charger/maintainer. One thing I’ve noticed is I’m not hearing the fuel pump kick in. But yes it’s getting spark and I put a new plug in and no change just cranks. Thank you guys 

[mlatour]

If the original battery was defective, did the dealership replace it? (you mention buying one from Rocky Mountain)

If a new battery has again failed, I'd return the bike to the dealership and have the bike checked for a parasitic drain in the electrical system.

[Jc32]

Yes the dealership did replace the oem battery but I also ordered one because theirs was going to take a while to get to me and I’m not close to the dealership. Also the bike is kept inside so shouldn’t be cold. I’m going to call them tomorrow and probably take the bike up there tomorrow as well. Do you know what the warranty covers? Like I said it’s 3 weeks old. Thank you 

[Jc32]

Yea it’s ran both new batteries dead so I went and bought the charger yesterday charged them to 100 and still just cranks 

[mlatour]

29 minutes ago, Jc32 said:

Do you know what the warranty covers? Like I said it’s 3 weeks old.

If it's a factory defect it should be covered but that is very depended on your regional laws and regulations

and the goodwill of the dealership. The replacement parts could be covered but not the labour.

 

In some markets, a closed-course racing / competition vehicle like this is sold brand new 'as-is' off the showroom floor with no warranty whatsoever,

meaning if it blows up/breaks down on the first ride, unless proven it's a factory defect and,

has happened within a limited number of hours of usage, nothing will be honoured.

 

If the battery is fully charged, the engine cranks/spins fine but does not start,

there is likely another issue than just an electrical current drain.

Are you pulling the 'starter' knob on the throttle body?

Are you twisting the throttle during starting attempts?

What does the owner's manual say about starting procedure.

 

 

Edited March 27, 2023 by mlatour

[ss-racing66]

Replace the spark plug, it’s likely fuel fouled.

[Jc32]

Yes sir I’ve tried with throttle and without and also tried with starter knob and without. They are closed on Monday so I should know if they will honor it tomorrow if not I’ll go somewhere else. The bike only has 2.5 hours on it 

[ss-racing66]

You don’t turn the throttle to start a 4-stroke. ….an once you foul it, it’s game over for that plug

[Jc32]

43 minutes ago, ss-racing66 said:

You don’t turn the throttle to start a 4-stroke. ….an once you foul it, it’s game over for that plug

Ok thank you I’ll grab a plug and no throttle thank you ss-racing66 I appreciate it 

[Jc32]

2 hours ago, ss-racing66 said:

You don’t turn the throttle to start a 4-stroke. ….an once you foul it, it’s game over for that plug

Anything I need to do before putting this new plug in and trying to start it? Thanks everyone for their help

[ss-racing66]

4 hours ago, Jc32 said:

Anything I need to do before putting this new plug in and trying to start it? Thanks everyone for their help

Make sure there’s some good gas in it. 😉

 

Also @Jc32 , always nice to let everyone know how you fixed it  .  Cheers 🍻 

Edited March 28, 2023 by ss-racing66

[beezer]

I've heard there is a reflash for the 23 YZ250FX's because of hard starting in cold temps.

Maybe the YZ250F has the same issue.

The reflash has to be done at the dealer.

[Jc32]

1 hour ago, beezer said:

I've heard there is a reflash for the 23 YZ250FX's because of hard starting in cold temps.

Maybe the YZ250F has the same issue.

The reflash has to be done at the dealer.

It’s running now but if I continue to have issues I’ll look into that thank you 

[chadk66]

Unless it’s over 70 my yzf required the cold start to be pulled on. Use that and zero throttle.  And don’t crank for very long without stopping.  Five to seven seconds should be enough. It is possible that your valves aren’t in spec. It’s not out of the question to have new bikes on the very edge of spec and they not like that. 

[jake22si]

We are having the same problem with a new 2023 yz250f.  Hoping the low 40's temps we have in the northeast are the issue.  Gone through 2 plugs so far in the 2 weeks we've had it.  Kids can't wait to ride.

[mlatour]

3 minutes ago, jake22si said:

We are having the same problem with a new 2023 yz250f.  Hoping the low 40's temps we have in the northeast are the issue.  Gone through 2 plugs so far in the 2 weeks we've had it.  Kids can't wait to ride.

Is the bike stored outdoors / in a unheated shop?

Doesn't hurt to 'pre-heat' the cylinder head up a bit with a hair drier or heat gun (not too close!)

for the day's initial cold start when in near freezing ambient temps.

[Yzf250-81]

Mine done the exact same 2nd day in battery died then about a few months in it stopped starting I thought it was spark when I took it to the dealership I got it they said it needed a top end got it done and it worked for around another 2 weeks then started eating spark plugs like a new plug was in it every 2 days and then it just was fine for about 8 months and then blew up bottom end nice bikes don’t get me wrong but they will cost you