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1997 RM250 Fuel dripping down cylinder walls

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So I recently bought a 1997 RM250 for pretty cheap, the guy claimed it had a top to bottom rebuild. From what I can see the bottom looks to be done, but not the top.

Compression is good but I looked down the spark plug hole and see alot of carbon buildup on the top of the piston.

Anyway, the bike is extremely hard to start, cleaned the carb, checked the reeds, I have fuel and spark and this is the only thing I think it could be. I will provide a picture of what I mean but when i took the intake and reeds off and looked in the intake, I could see fuel dripping down the sides of the cylinder. Could it be blown rings/ old piston? I'm out of ideas..

Picture of the fuel dripping: https://imgur.com/a/xWF89

Thanks guys :thumbsup:

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Honestly I'm not perfectly sure about that. Could be residual oil/fuel mixture that collects in the exhaust port that then runs back down into the cylinder after it sits. That'd be my best guess. If it has a lot of carbon buildup, might be that it has more hours on it than PO realized/wanted to admit. May have needed a slight oversize on ring/piston last time it was done and didn't get it. Can never know for sure when you buy a used bike. Best bet is to start with the simple stuff first and work your way up. Carb may be clean, but did you check jetting and float level? Carb may be adjusted wrong and running too rich. How's the spark plug look? Clean and gapped correctly? Correct part number? All the little stuff like that. If enough small stuff isn't correct, it can add up and cause a seemingly big problem. Either that or you can always check compression and try to rule out top end that way.

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10 hours ago, criggs88 said:

Honestly I'm not perfectly sure about that. Could be residual oil/fuel mixture that collects in the exhaust port that then runs back down into the cylinder after it sits. That'd be my best guess. If it has a lot of carbon buildup, might be that it has more hours on it than PO realized/wanted to admit. May have needed a slight oversize on ring/piston last time it was done and didn't get it. Can never know for sure when you buy a used bike. Best bet is to start with the simple stuff first and work your way up. Carb may be clean, but did you check jetting and float level? Carb may be adjusted wrong and running too rich. How's the spark plug look? Clean and gapped correctly? Correct part number? All the little stuff like that. If enough small stuff isn't correct, it can add up and cause a seemingly big problem. Either that or you can always check compression and try to rule out top end that way.

I've cleaned the carb, jetting is stock, float level is stock, needle valve is closing and opening as it should, checked and cleaned the reeds, checked for airleaks, compressions good, spark is good and the odd time (about 1/100 kicks) I get it started it sounds decent, doesn't smoke a lot and the spark plug comes out a nice brown colour. I looked in both the intake and exhaust and the rings look fine, no blowby.. I have no clue what it could be, maybe the spark isn't strong enough or the timing is off? I have no clue 

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That is definitely strange. I'd go over the entire electrical system and make sure that all the resistances are what they need to be. I'd also do a compression test as well. I've heard of a similar issue before where the bike ran amazing, but was extremely hard to start cold. Turned out it had a top end done but was not broken in properly and had poor compression when cold, but totally normal when warm/hot. Might have something wacky like that going on. Whatever it is, it's definitely fixable, just gotta find the problem =P.

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Fuel should not be dripping down the walls. First check your plug, is it wet? Next MAKE SURE it’s fuel you see dripping and not coolant. Could be a loose head and bad head gasket. What condition is your carb in? You said you cleaned it, how’s it look on the inside? Also what do your reeds look like?

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On 2/9/2018 at 1:22 AM, ASP1227 said:

Fuel should not be dripping down the walls. First check your plug, is it wet? Next MAKE SURE it’s fuel you see dripping and not coolant. Could be a loose head and bad head gasket. What condition is your carb in? You said you cleaned it, how’s it look on the inside? Also what do your reeds look like?

Plug is wet but not fouled, it isn't coolant it looks almost a brownish color, carb was cleaned up just got a rebuild so it looks very new, reeds are nice, closed and no cracks.

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Plug is wet but not fouled, it isn't coolant it looks almost a brownish color, carb was cleaned up just got a rebuild so it looks very new, reeds are nice, closed and no cracks.

It sounds like it’s flooding. Did you check to make sure the floats are sealing in the carb?

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