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Knocking on decel..?

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I've been wondering how much if any knocking I should hear in the low RPM range on decel. My 300 seems to be doing it a lot more than I recall when I first got it. I've been under the impression this is caused by a lean condition and that by going up to a 38 from a 35 pilot would resolve it. I tried that and while it seems to idle a little smoother it does nothing for the popping/knocking I get during decel.

So I'm curious if any of you 2t nuts might be able to steer me the right way on this one.........?

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it could be the diameter of the needle, AS, or clip pos, or a combination. adjust each one at a time, eliminating the innocent as you go. Mine was doing that recently due to the colder weather and I took care of it by going to a richer diameter needle. Richer pilot didn't completely eliminate mine either, neither did clip pos.

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Well today I tried all these settings

1. 165 Main / 35 pilot / clip pos #2 N2ZJ (strongest pull so far)

2. 165 M / 38 P / clip #2 (felt flat from 3/4 throttle and up, still knocking)

3. 162 M / 38 P / clip #3 (results close to previous only a little flatter)

4. 165 M / 35 P / clip #3 ( little change, still knocking and feeling rich/splooging now to)

Finding an easier way to change this would be nice. Removing seat/Tank/Slide the twisting carb and draining the fuel is such a PITA and messy. It would be nice if they would have a better way to drain the fuel bowl, like they do for the newer 4t's.

This my friends is why DI will be sooooooo nice!

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I think what you're experiencing is pipe bang. The 300's do it and you won't be able to jet it out, but the good news....it's harmless. Do a search on KTM Talk for "pipe bang" to put your mind at ease.

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You know I just recalled from something I remember reading a few years back about exhaust rings leaking. Seems like if those seals are leaking it can cause a knocking sound. Does things ring a bell for anyone else?

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it could be pipe bang. Raising the main has nothing to do with it, so if you are close there, then don't mess with it.

IF is it attributed to jetting, I would find the next step richer diameter needle.

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you can jet it out but you actually have to lean one or more of the lower end circuits .....pilot/taper/slide. this problem must be more pronounced in the winter because of the richer jetting people use in the winter if you jet your bike to run right when totally warmed up (which is gonna be lean for the 1st 15-20 minutes ) its not as bad...of course this makes for harder cold starting but the benefits will be appreciated as the day warms along with the motor.

if you do jet like i've described to help when its really cold you can richen the a/s and then reset it.:thumbsup:

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Bear in mind, as well, that in cold dense air that we have in winter then bangy/tappy noises are always more pronounced. Also, when you notice a noise, you always end up hearing it more and more and more and can end up convincing yourself it's getting worse, when it may not be.

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Bear in mind, as well, that in cold dense air that we have in winter then bangy/tappy noises are always more pronounced. Also, when you notice a noise, you always end up hearing it more and more and more and can end up convincing yourself it's getting worse, when it may not be.

Funny how that is huh.............

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its a 2st, they do that noise. As long as it doesnt continue once you stop and idle for a few seconds then its OK. If it continues after a few seconds of idle then it got hot in the part of the throttle you were riding in, meaning it may be lean in that part of the throttle. So if idling along then its pilot/slide, if cruising at 1/4 to 1/2 maybe its the needle, etc.

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i spent alot of time trying to get rid of it and it only went away when things were leaned off idle,one factor that really got rid of it was when i tried a #8 slide and just for kicks i had a #6.5,which is a bit richer than stock (stock is 7 and higher # is leaner) but had no notch in the bottom....it was better as well,so i figured i'd run that for winter and switch to the 8 later. so basically thats telling me it was too rich on the the chop. it also reduces with slightly leaner needle configurations(not clip pos)

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