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2004 cr250 bogging

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Got a cr250 about a month ago and rode it for the first time today. Beginning of my first moto it was bogging a lot, then got a little better bogging a few times a lap, came close to wrecking a few times cause the bogging.

At the track I drained the old gas and put new gas in, that didn't help at all. Could the problems be the jets are clogged?

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It sounds like your jetting is off I'd start there.   Do you have a manual ?

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I would start with checking your plug and air filter then clean the carb.

Since he just rode the bike for the 1st time that would be a better place to start, but I assumed he would have checked the basics before going out to his 1st moto. 

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Since he just rode the bike for the 1st time that would be a better place to start, but I assumed he would have checked the basics before going out to his 1st moto. 

Definitely check that stuff before you fiddle with the needles and jets.

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I'm going to clean the air filter and check the plug before messing with the carb. I bought the bike in Florida at sea level, and I'm riding it in Georgia at about 1000 feet. Could that small amount cause the bog.

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I would start with checking your plug and air filter then clean the carb.

 

yeah that stuff isn't hard, you just have to take the time to do it.  I've done it at the practice of a race for my buddy, whose bike was cutting out on bottom bc his pilot jet was clogged.

 

He didn't wanna take it apart, but I ensured him that it's not hard to rip out the carb and take off the float bowl.  He was glad we did it.

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So would 1000 feet change in elevation cause bogging issues?

Nope. What a little elevation change CAN do is make a bike that was running too fat or lean go over the edge on jetting. If you are spot on you won't have a problem. Start with 2 steps leaner on the main after you take care of the plug and filter.

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I took my jets out and the main is a 420 (stock size I believe) and the other one is a 32.5 (think stock is 30).

What direction is recommended on the jets to get rid of the bog issues? I think the engine is all stock, and I have a FMF pipe, live near Atlanta at 1000ft.

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I'm no absolutely positive, but that sounds way rich. Is it hot and humid in Georgia right now? 27.5 pilot and 390 main sound better to me. Check pro circuit's jetting recommendations to be sure. Should get you close.

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If the jetting doesn't help then i would check the operation of the power valve. Just take the cover off and start it up, once it's warm you can give it some revs and you should see the valve operate. From memory, it alternates position while the revs are been 4 and 6.5k and after that it is wide open. It may be that the shaft is seized or the motor is not operating. I had a cable snap on my powervalve once too. I also had a hole in my reed valves cause a bogging issue that mimicked poor jetting very well.

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Should I just buy the same jets I have but new? I would clean them, but I am worried I'll think it's fixed then get to the track and it'll still bog. If I ride it down the road to test it, it won't necciraly bog.

Pro circuit jet chart recommends what I currently have in it.

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You're going to have to test it before the next race regardless because you won't know if it's fixed until you try it.

Clean it up, if it's the recommended settings then look elsewhere. Like the guys said, check out the PV operation. Have a look at the reeds. Go through all the possibilities and you'll have the least chance of still having problems next time you're out.

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You're going to have to test it before the next race regardless because you won't know if it's fixed until you try it.

Clean it up, if it's the recommended settings then look elsewhere. Like the guys said, check out the PV operation. Have a look at the reeds. Go through all the possibilities and you'll have the least chance of still having problems next time you're out.

Would spraying carb cleaner and blowing air through the jets be just as good as buying new ones?

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Would spraying carb cleaner and blowing air through the jets be just as good as buying new ones?

 

No, and you can get new jets for a little more than a can of carb cleaner.

Edited by Keith72

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I had the same problem on the weekend. I have a pwk screw top with 175 main jet. Went to a new location and had to put a 160 main jet in it to clear up the bog.

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I had the same problem on the weekend. I have a pwk screw top with 175 main jet. Went to a new location and had to put a 160 main jet in it to clear up the bog.

Thats not possible. You should never have to rejet a pwk.......

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Friend had a yz250 had a 150 main in it. 30deg +. 95% + humidity. Sea level. I thought no way as well. But I was proven wrong. But I am rebuilding bike this week, crank and piston. So I will see if it was that.

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I ordered new jets from jets-r-us. A 420 and 32.5, same that's in the bike now.

How to my reeds look, and are they stock? They seem to seal we'll, and are a little chipped on one of them. That small amount of chipping couldn't cause the bog, could it?

Also, the white plastic piece that goes in after the reeds, what happens if you put that in backwards?

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