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2004 honda crf250r rich mixture?

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hey guys, I have a 2004 honda crf250r running rich. I'll give you an idea of my bikes situation. The bike has been running great no problem until today I started the bike let it idle and suddenly after about 5 minutes of running it shut off and wouldn't start after. I removed my plug and it was oil fouled. I have since replaced my spark plug with a new oem one. About a month ago I did the AP mod to my carb due to some bog. And I rode it about 3 weeks ago. I have checked my timing and valves all is good.. I think I am running way to rich. Would I have to run a lower leak jet to solve the problem? I also have a boysen quickshot 2 acc. Pump cover installer at same time as ap mod. No idea where to start on a carb but help is appreciated I haven't rode the bike for three weeks also. Would a rich mixture cause a no start? The bike is back firing and starting for a second then dying. Any questions feel free to ask

Edited by m.carpino03

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hey guys, I have a 2004 honda crf250r running rich. I'll give you an idea of my bikes situation. The bike has been running great no problem until today I started the bike let it idle and suddenly after about 5 minutes of running it shut off and wouldn't start after. I removed my plug and it was oil fouled. I have since replaced my spark plug with a new oem one. About a month ago I did the AP mod to my carb due to some bog. And I rode it about 3 weeks ago. I have checked my timing and valves all is good.. I think I am running way to rich. Would I have to run a lower leak jet to solve the problem? I also have a boysen quickshot 2 acc. Pump cover installer at same time as ap mod. No idea where to start on a carb but help is appreciated I haven't rode the bike for three weeks also. Would a rich mixture cause a no start? The bike is back firing and starting for a second then dying. Any questions feel free to ask

shouldnt be oil on the plug. See if your valve seals are all on the guides good, then I would say rings are bad. Again, oil fouled on a 4 stroke is not usual.

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A rich mixture would not stop the bike from starting cold, in fact the purpose of the choke is to richer your mixture. What makes you think it's running rich? Is this a new symptom? It might be as simple as a good carb cleaning. Don't make it too complicated.

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A rich mixture would not stop the bike from starting cold, in fact the purpose of the choke is to richer your mixture. What makes you think it's running rich? Is this a new symptom? It might be as simple as a good carb cleaning. Don't make it too complicated.

he oil fouled a plug, so he has an oil issue. Oil fouling on a 4stroke is either a bad valve seal or rings that are worn out badly. No way should oil touch the plug on a four stroke.

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A rich mixture would not stop the bike from starting cold, in fact the purpose of the choke is to richer your mixture. What makes you think it's running rich? Is this a new symptom? It might be as simple as a good carb cleaning. Don't make it too complicated.

I clean all my jets last night with honda carb cleaner and compressed air hooked up the carb and it ran fine for 10 seconds. Went back to bad idle after I'm going to replace all my jets and needle with new oem ones my rings are new aswell with my solves. I think your correct on this issue my Haynes Manuel also says a foul plug first check mixture and a rich mixture will cause a fouled plug

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A rich mixture would not stop the bike from starting cold, in fact the purpose of the choke is to richer your mixture. What makes you think it's running rich? Is this a new symptom? It might be as simple as a good carb cleaning. Don't make it too complicated.

. The bike was running fine up until the AP mod. Is there any other way to determine if my rings are gone other then doing a leak down test? I clean the carb and it ran well for a couple seconds then started to act up again, I'm going to try replacing all the jets with fresh ones and see what happens.

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. The bike was running fine up until the AP mod. Is there any other way to determine if my rings are gone other then doing a leak down test? I clean the carb and it ran well for a couple seconds then started to act up again, I'm going to try replacing all the jets with fresh ones and see what happens.

If it ran fine before the ap mod why don't you try reversing that first instead of throwing expensive parts at it? A leak down test is the only way I know of to troubleshoot your problem but maybe someone else will chime in here with another idea. It still sounds like a carb issue to me.

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I put all original parts back in carb, still ran funny... I think there's an issue with my jets, there all ten years old so it dosent hurt to change

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Have you set your air screw?

If that's the mixture screw inside the carb no I haven't touched that at all, only the idle screw on the outside.

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