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Dead spot down low after FCR/ DRZ400SM

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I read another post where someone asked how to adjust the accel pump on an FCR carb, to eliminate a dead spot right off idle.

I don't know if that is my problem or not but here is the set up.

2005 DRZ400SM

Full Yosh RS3 no insert

3x3 that is more like 3x4 mod

FCR Sidedraft 39mm

165 main

45 pilot

2 1/2 out fuel screw

200 main air

JD blue needle 3rd clip down

It runs great except right off idle, there is this nasty completly dead spot. It comes out when you turn in after down shifting and going to power through a turn it will go dead when you get on the gas,, then go great. It is not noticable or does not do it when pulling out or between up shifts. I also noticed that when I come home in the morning when it is nice and cool out, it does not do it till the bike is nice a warmed up.

Is this an accel pump issue or is my needle set too lean, or something else too lean? It still pops a bit on deceleration, going to 2 1/2 out on the fuel screw fixed it somewhat and it has much better low end at this setting. But the dead spot is there regardless of the fuel screw setting, I have tried 1 1/2 - 3 1/2 out.

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Ebay, I believe it came from a YZF400. The owner had purchased it used on ebay along with all the boots and the Jetting kit I think he got that stuff from TT store.

I was thinking the carb needs new seal and accle pump diaphram? Who knows how long it has be sitting. Would that stuff cause it to do what it is doing? I disasembled and cleaned the carb well, the above mentioned parts did not look all that good.

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You think the carb slide maybe sticking when it gets warmed up? Anything else I can check? Could it be the accel pump diaphram it was a bit brittle looking?

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they dont stick.the slide plate breaks.

it possible the pump diaphram is bad as well.

used fcr carbs are gamble.thats why so many shy away from them.

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Its really not a big deal. My dealer is excellent at obtaining me parts. They have a nice parts list break down at Sudco I can get the Keihin numbers from there and my dealer should be able to get me the parts.

Thank you Ed

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