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Exhaust poof on shutdown?

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Is it normal for the exhaust to make a poof sound when I kill it or does this sound like a jetting issue?

Thanks

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4 hours ago, spin05 said:

mine does it. And i have been re-mapped

Thanks Spin. My bike is still carbed so I can't change any maps but I was just wondering if it was a sign of being to rich or something.

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Not sure what actually causes it. I have a fmf pipe but i never rode with the stock pipe

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1 hour ago, spin05 said:

Not sure what actually causes it. I have a fmf pipe but i never rode with the stock pipe

Mine came with the FMF Power Bomb but has a stock silencer on it, not sure if that's good for it but o well haha.

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I suppose an exhaust header leak would do it.

You could also fiddle with the fuel screw. Under the carb near the front of the bowl.

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On 8/1/2017 at 6:15 AM, numroe said:

I suppose an exhaust header leak would do it.

You could also fiddle with the fuel screw. Under the carb near the front of the bowl.

I haven't adjusted the fuel screw yet but I don't think that the header has a leak either. My bikes seems to start and run good, I do know on a cold start with the choke on the bike will stay running but if i start it and shut the choke off after a few seconds the bike will want to die out. I basically just start with the choke on and give it some throttle and then turn off the choke and take off riding and once the bike is warmed after a lap on the track its fine. I have messed with the idle and I don't have it to high or to low so it should be good to go. 

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Best if the problem wasn't there. If the bike runs well generally, it still might be  a tell tail sign that something isn't right. My thoughts are: Fuel screw adjustment. Header leak because the seal ring wears out. Worn valve leaking in the head.

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According to the previous owner he mentioned a couple times that the top end was just redone, but you know how that goes. I do know that the fuel screw is in an awkward spot on the carb and that the service manual calls for a special screw driver to get up in there. Hopefully I can get a small screw driver in there fairly easy and turn it the 2 turns out as that is what's specified in the manual. A few rides ago I had an awkward situation, I noticed my idle was to high and the bike was already warm so I turned the knob and lowered the idle to what sounded better. The following ride at the end of day I noticed my idle was high again and I had to back it down. The previous owner mentioned that the hot start would occasionally stick. Could that be the cause of my issues? My bike starts great hot or cold and even after a crash so I am not really wanting to start messing with jets. I have a theory if it's not broke don't touch it lol. But I also do not want to damage anything.

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On 03/08/2017 at 11:10 PM, IraqvetUSMC said:

The previous owner mentioned that the hot start would occasionally stick. Could that be the cause of my issues?

Yes indeed, that could be the problem. If the hotstart plunger sticks open just a little then it let's air bypass the slide and jets. You should remove it, clean and lube the plunger and full lube+flush the cable before you reinstall it.

On 03/08/2017 at 11:10 PM, IraqvetUSMC said:

I have a theory if it's not broke don't touch it

That kind works. But it depends what you define as being broken. When there is a small sign of a problem that's usually the time to go looking and fix it. Not only to save bike $, but for safety reasons too. You have to do preventative maintenance too. Consider what happens on the track when your throttle sticks open or your brake caliper falls off.  You have to choose your risk levels and equipment prep is part of it.

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20 minutes ago, numroe said:

Yes indeed, that could be the problem. If the hotstart plunger sticks open just a little then it let's air bypass the slide and jets. You should remove it, clean and lube the plunger and full lube+flush the cable before you reinstall it.

That kind works. But it depends what you define as being broken. When there is a small sign of a problem that's usually the time to go looking and fix it. Not only to save bike $, but for safety reasons too. You have to do preventative maintenance too. Consider what happens on the track when your throttle sticks open or your brake caliper falls off.  You have to choose your risk levels and equipment prep is part of it.

I will remove, clean & reinstall the hot start cable before I mess with anything else. Sounds like that might be the reason why it was idling so high sometimes. You are right on preventive maintenance as for cost and safety in the long run. I was more referring to not wanting to mess with the carb other than adjusting the pilot screw and since the bike starts easy hot or cold and generally runs good lol.

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