carb is starving at low rpms?
#1
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HELLO ALL
I need help with my 04 1200 roadster the problem is at a low rpm or when i take off the engine it miss firing poping then it takes right off. on the hwy i have no problems at all. lots of power but under 1500 rpm it pops wants to stall.I installed all new carb parts and cleaned. after the engine gets up to temp all heck breaks out. why at low rpms not higher.
Thank you all for any help
MIKE
I need help with my 04 1200 roadster the problem is at a low rpm or when i take off the engine it miss firing poping then it takes right off. on the hwy i have no problems at all. lots of power but under 1500 rpm it pops wants to stall.I installed all new carb parts and cleaned. after the engine gets up to temp all heck breaks out. why at low rpms not higher.
Thank you all for any help
MIKE
#4
#7
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I just bought a 2004 Sportster Roadster 1200 and have the same thing. Bike runs like a champ, except cruising at a steady speed with rpm between about 1500 to 2200. doesn't matter what gear or speed. The pipes do look (and sound) to be aftermarket thought the owner wasn't sure. He put about 130 miles on the thing in 2 years so didnt know much about it.
But yeah, adjusting the mixture is my first option to try. Only had it a week now
But yeah, adjusting the mixture is my first option to try. Only had it a week now
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#8
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I just went through this crap with my OL's '04 1200C. It would idle fine, but it had no power when you tried to start off. A stumble directly off of idle. Once you got it going, it would run better at higher rpm. It seemed to get worse as the engine got warm. I fiddled with the carb, putting in a new (part #27170-89) 45 jet and re-setting the air/fuel screw to 2.5 turns out. It seemed to be better, but 30 miles into a ride it acted up again. It was the crank position sensor. I installed the new sensor about 400 miles ago and it's running great. About 50 bucks, part # 32804-04B. Be prepared - you will loose oil when you pull the old one out, even when the bike is sitting staight up. About a quart, less if you move fast. I just let it come out and added a fresh quart when I was done cleaning up the mess. There are some other threads about the crank position sensor if you do a search.
Let us know what happens.
Let us know what happens.
Last edited by HarleyScuba; 04-19-2012 at 07:51 PM.
#9
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I'm a new Harley owner with less than 100 miles on my restored 80 sportster. I took it in for a check-up since I'm not a mechanic. They did a once over and showed me some things. One thing the guy mentioned was to ease it from a stop and not just gun it. He said once I get an S&S and bring the carb out of the 60's technology then I would have a hot rod. Not his exact words but that's how I heard it. When the light turns green and I give it some gas and start rolling, it starts to sputter a bit, I shift into second and the engine improves but still sputters until I get into third. Once I get going, I'm ok. Any ideas? Same symptoms as the originators thread. I doubt my bike has a crank position sensor.
Thanks. Nick
Thanks. Nick
#10
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I just went through this crap with my OL's '04 1200C. It would idle fine, but it had no power when you tried to start off. A stumble directly off of idle. Once you got it going, it would run better at higher rpm. It seemed to get worse as the engine got warm. I fiddled with the carb, putting in a new (part #27170-89) 45 jet and re-setting the air/fuel screw to 2.5 turns out. It seemed to be better, but 30 miles into a ride it acted up again. It was the crank position sensor. I installed the new sensor about 400 miles ago and it's running great. About 50 bucks, part # 32804-04B.
Be prepared - you will loose oil when you pull the old one out, even when the bike is sitting staight up. About a quart, less if you move fast. I just let it come out and added a fresh quart when I was done cleaning up the mess. There are some other threads about the crank position sensor if you do a search.
Let us know what happens.
Let us know what happens.
That should not happen! I didn't lose a drop on my '05 when replacing the sensor. Either the position of the sensor was moved higher on the newer bikes (not likely) or your bike is wet sumping. When you change your oil, how much do you put in??