CRF 250r Jetting.

I know everyone will refer me to the manuals, but what jetting have people on here been having at 4500ft elevation on a totally stock bike? I am just getting tired of my bike running like a swather.

First, you have find out what jetting is actually in your bike. 'Stock' is not an answer. Next, you have to accurately explain what running problems you have. 'Swather' again, is not an answer.

Based on what you say, you are probably rich. 'Rich' too. is not the answer.

Of the total throttle travel, note in 1/8ths or a turn, what the performance is like. These tests need to be done on an incline, in 3rd or 4th gear. You want to do a series of 7 steady throttle runs, noting how the bike seems each time. Then based upon the actual jetting in the bike and your clear description of how it runs, can accurate suggestions be made as to what jetting you need to try. Then you put it in and re-test, reporting back.

I was not saying my jetting was "stock". I know I am running rich in the higher rpms, but my idle is just fine and it runs just fine on the pilot. I was just looking to see if anyone at my elevation had any luck with a certain size and combo of jets. As for your description of the testing, i am a bit confused. I know i can do trial and error to find a better jetting solution. I was simply wondering if anyone had any luck with a certain jetting at 4500 feet on a non modified bike.

Every bike is slightly different as is every riders preferred operation. When jetting, not only does that have to be taken in to consideration but temperature, humidity and air pressure. Elevation really does not matter. So for someone to spout off jetting that will work for you, they would have to have an identically setup bike as you, in the same temperature, humidity and air pressure.

I can give you jets to try but they could be worse than you already have.

But try this:

Drop the needle two clips (move the clip closer to the top/flat)

Put in a one size smaller main jet.

Thank You William1. I just have a slight knowledge on jetting, so every bit of info helps.

You should always first find out what you have to start with. Stock jetting may or may not actually be in a new bike. Then write it down in a note book. As you make changes (one change at a time) make notes on how the bike is, better worse, when where...

FYI - All bikes are supposed to be jetted from the factory for 30 inches of mercury, 68 F degrees and 50% humidity.

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