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Discussion Starter #1
ok, so as if its not enough that the alternator went out on my truck and ill have to wait till wednesday before i get that...the bike has started to misbehave. its an 06 with 1050 on the clock. its been in the 30's here all week, so im wondering if cold or humidity (also been quite humid) has a part to play in this. so a couple days ago i noticed that i could start the bike up fine, pop it into gear, and go. id ride down to my classes (~15 miles) and when id come to a stop the engine would just stall out. and in order to start it up it took a bit of throttling to get it up and stay lit. so yeah..its been annoying but today was a different story. got off work to go home...REALLY not wanting to run..not even just sitting there at idle. never had a prob before. when i hop on to ride..i noticed only 1 cyl is firing. so im riding along..and after a bit the bike comes to life and i get the 2nd cyl back. did a little hiccup..then was ok except for stops...still wanted to stall. so i get home, park, take off my gear, and go out to do some snooping. i start it up with very little choke and she purred like a kitten. revved it up...sounded great. WTF is going on? i couldnt imagine its the gas cuz i put fresh in last week and it didnt act like that.

anywho, i guess ill go pull the plugs tomorrow. thats just odd that it started doing that. and after it got a little warmer it acts like nothing ever happened. it wouldnt be so bad if this wasnt my only means of transport for the next 4 days...but this is rediclous! if this dosent clear up by the time i have my truck im gonna trailer the SOB into the kawi dealer cuz i didnt pay for that extended warranty for nothin.

in the mean time..ideas?
 

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Sounds like your Icing up the carbs. Cold and Humid will do it. The pressure drop at the venturi bridge that draws the fuel through the main jet also causes a temp drop (see Refrigeration) this is enough to form ice on or near the throttle plate, at small openings (Idle) this ice closes the opening causing a stall. After the bike sits a few min. engine heat finds it's way there and the ice melts.
Because the carbs are rubber mounted to quell vibes the heat transfer is also disconnected. Cars BTW have heat risers or even water heated intake manifolds fore this very reason.
Not much you can do except raise the idle speed to 2000 or more.

FOG
 

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FOG said:
Sounds like your Icing up the carbs. Cold and Humid will do it. The pressure drop at the venturi bridge that draws the fuel through the main jet also causes a temp drop (see Refrigeration) this is enough to form ice on or near the throttle plate, at small openings (Idle) this ice closes the opening causing a stall. After the bike sits a few min. engine heat finds it's way there and the ice melts.
Because the carbs are rubber mounted to quell vibes the heat transfer is also disconnected. Cars BTW have heat risers or even water heated intake manifolds fore this very reason.
Not much you can do except raise the idle speed to 2000 or more.

FOG
I concur ;D
 

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Discussion Starter #4
thanks fog, i was hoping youd be one to respond. im glad to hear that its nothing serious. hopefully its mostly the humidity causing the icing. its been unusually humid here. come to think of it..ever since the fog rolled in a couple days ago...thats when it started. its been foggy really bad in the mornings and evenings..and light all day. maybe once things clear up and get back to being so dry it will quell.

thanks again yall!
 

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ex_dsmr said:
thanks fog, i was hoping youd be one to respond. im glad to hear that its nothing serious. hopefully its mostly the humidity causing the icing. its been unusually humid here. come to think of it..ever since the fog rolled in a couple days ago...thats when it started. its been foggy really bad in the mornings and evenings..and light all day. maybe once things clear up and get back to being so dry it will quell.

thanks again yall!
If you ride in humid-cold environment, block 3/4 of radiator (evening time mostly) - you should be just fine!
Cheers!
 

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FarFetched said:
ex_dsmr said:
thanks fog, i was hoping you'd be one to respond. im glad to hear that its nothing serious. hopefully its mostly the humidity causing the icing. its been unusually humid here. come to think of it..ever since the fog rolled in a couple days ago...thats when it started. its been foggy really bad in the mornings and evenings..and light all day. maybe once things clear up and get back to being so dry it will quell.

thanks again yall!
If you ride in humid-cold environment, block 3/4 of radiator (evening time mostly) - you should be just fine!
Cheers!
That may help a little, but the real problem is not the engine temp but the Isolation of the carbs from the engine heat, and of course the refrigeration effect of the venturi. Small airplanes have a Carb Heat knob to direct exhaust manifold heat to the carb for the same reason. This is only a problem in the described conditions Cold Humid weather

FOG
 

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FOG said:
FarFetched said:
ex_dsmr said:
thanks fog, i was hoping you'd be one to respond. I'm glad to hear that its nothing serious. hopefully its mostly the humidity causing the icing. its been unusually humid here. come to think of it..ever since the fog rolled in a couple days ago...that's when it started. its been foggy really bad in the mornings and evenings..and light all day. maybe once things clear up and get back to being so dry it will quell.

thanks again y'all!
If you ride in humid-cold environment, block 3/4 of radiator (evening time mostly) - you should be just fine!
Cheers!
That may help a little, but the real problem is not the engine temp but the Isolation of the carbs from the engine heat, and of course the refrigeration effect of the venturi. Small airplanes have a Carb Heat knob to direct exhaust manifold heat to the carb for the same reason. This is only a problem in the described conditions Cold Humid weather

FOG
Ever since I've blocked off radiator, I haven't had any idle problems. I do about 30 nim hwy run at late night so temps are colder.
If I keep my EX longer, I might get lower cowling from Targa for aesthetics and functioanality.
Anywho, keep engine at normal op tems is a lot better than running it cold(water condesation formation equals corrosion)...
Cheers!
 

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Not that this'll help any, but Older carbureted small planes had the same problems so they had carb-heat to avoid losing power on takeoffs during cold days w/ high humidity.

PDF file: http://www.aopa.org/asf/publications/sa11.pdf
 

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I said that what are you a Parrot??

He He

FOG
 

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Um, Oops. I though it sounded familiar.
It's a hazard of losing track of what's written on different threads, on the job & in my reading (Notice I'm not saying age... DANG, I just did!): losing track of what's said where.

Hopefully the website will be of interest to those who wanted more info related to carb icing.
 

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Discussion Starter #11
well its kinda annoying..but thats what it was. it was like 70* the next day and she ran like a scalded cat.
 
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