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'05 WR250F Cold start problem

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Two weeks ago I noticed my bike was becoming hard starting with the "magic" button and I ended up kicking it over. I charged the battery last week on a trickle charge until the charger said full.

Went out this weekend and no start at all with the button when the bike was cold and had to kick it over, however, once the bike was warmed up the button started the bike right up.

I am thinking two things, battery is actually weak and is not providing enough cranking amps when cold, I have not put a meter on it while turning over the motor, I will do that tonight or the valves are tight. The latter is out since I had the valves adjusted just over 300 miles ago (I do it every 800 or so).

Just looking for some other things to possibly look at tonight if the battery is putting out the proper amperage.

Thanks,

David:ride:

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Define hard starting. Is it cranking over but won't fire? Or does it not crank over? When you kick it does it start right up or does it take a lot of kicks. If it isn't cranking over, but starts right up when kicked, you may need a new battery or it may be some sort of an electrical issue. If it doesn't start easily when kicked then it is most likely valves that are out of spec or a jetting issue.

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Cranks but will not start. I actually replaced the plug two weeks ago when the problem first started and I checked to make sure it was creating a spark with the button before I intalled it.

As for the overall starting. Again, this only happens when the motor is cold, the bike will crank but not start with the button, when you kick it may take three or four kicks and fires right up. Once you ride for five minutes or so the bike starts right up with the button. I have the valves adjusted/checked quite frequently and only once have they actaully come back out of spec and they were checked just 300 miles ago but it is possible.

I may just stop by the dealer and get a new battery since it the easiest thing to eliminate.

Just for my information, what could cause jetting to just go bad if that is a possible cause of the problem?

Thanks,

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If it is cranking over then it is most likely not a battery, electrical, or starter problem. It either isn't getting proper compression (out of spec valves), isn't getting spark, or isn't getting the proper air/fuel ratio. Since you changed the plug, you most likely ruled that out. If you check your valves you will rule that out easily. You can make sure you are getting spark by taking the plug out, putting the cap on it, holding it against the engine and cranking it over. If you see a spark then you are fine. Jetting must be adjusted for changes in temperature, humidity, and elevation. If the weather has changed then you will have jetting issues. Jetting can also be affected by some sort of obstruction clogging a jet in the carburetor. Hard starting is normally caused by an incorrect pilot circuit. You may have something clogging the pilot jet, in which case you will just need to clean it out. Your pilot circuit may also just be off due to weather changes. You will need to turn your fuel screw, or change the pilot jet f needed.

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It really sounds like one or more of the intake valves are gone. If they've been adjusted once and you dont know by how much they could already be toast.

Mine were out once so badly I re-shimmed for the sake of a quick ride and they were out of spec again after less than 100miles. Time for you to do a top-end rebuild I'd be guessing!! Sorry

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Once it warms the valves will be seating allowing it to start.

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I will know in two days if I am right but here goes for now.

I have noticed that when the starter does not provide sufficient cracking speed, she does not fire up where one good kick does. I had similar problems bad starting in past weeks. Charged battery and then she fired ok. As battery goes down I had to kick (once or twice). However, lately the battery did not solve the problem so I checked starter motor brushes - they were down to minimum and stator has markings on indicating bad contact (I think it is called "stator is dragging").

I suspsect I could have saved me $50 by checking starter motor first as the insufficien cranking speed was caused by starter motor and not battery.

Will let you guys know.

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