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BikeRider12345 · 06-22-2009, 08:47 AM

I have a 1980 Honda CB750K. It starts right up, but it sounds like air is escaping from the mufflers every once and awhile. What could that be from?

pushrod · 06-22-2009, 08:56 AM

Assuming you don't mean the air is coming out of the back, where do you think the 'leak' is?

At the head, midbody, joint(s), etc.

BikeRider12345 · 06-22-2009, 10:04 AM

It is coming out of the back of the muffler. I should have been more specific. It comes in short bursts, it sounds like an air compressor going off. Just happens every 15 seconds or so. Is it a carb timing issue?

MOKE1K · 06-22-2009, 11:12 AM

Ah, ahem,...I am lost?

BikeRider12345 · 06-22-2009, 11:55 AM

When the bike is running, I will here a noise come out of the muffler about every 15 seconds that sounds like an air compressor. Just like a burst of air. That is the best I can explain it. Not a normal sound for an exhaust. I am just wondering if it is a synching issue or what. I think it is only the left muffler.

seruzawa · 06-22-2009, 11:56 AM

Quote:

Originally Posted by BikeRider12345

When the bike is running, I will here a noise come out of the muffler about every 15 seconds that sounds like an air compressor. Just like a burst of air. That is the best I can explain it. Not a normal sound for an exhaust. I am just wondering if it is a synching issue or what. I think it is only the left muffler.

I'd pull the muffler off and see if something has come loose or is blocking it.

mscuddy · 06-22-2009, 12:55 PM

Buy a Kerker reproduciton for anout $150.00. The "F" model had that big goofy pipe on it that had more crap in it than my roll-a-way filled with jig saw puzzles. Not only will it perform better, you'll get that 70 lb. salami off the left side and it will handle better too.

Face it, your 25 plus old exhaust pipe has more holes in it than Bill Clinton's tenor sax. It might sound better but that's the price we pay sometimes.

acecycleins · 06-22-2009, 02:28 PM

Is this KP messing with you guys.

What is a motor- an air compressor with a purpose. Air, fuel, ignition- throttle and so it goes.

Check the seating at the motor at the header. I used to have a old Bonni that had a crack at the top of the pipe. It would puff very little smoke out of that hole, but you could hear it when standing behind the bike.

MOKE1K · 06-22-2009, 03:42 PM

I Know Its Your Muffler Bearings!!!

seruzawa · 06-22-2009, 03:46 PM

Quote:

Originally Posted by acecycleins

Is this KP messing with you guys.

What is a motor- an air compressor with a purpose. Air, fuel, ignition- throttle and so it goes.

Check the seating at the motor at the header. I used to have a old Bonni that had a crack at the top of the pipe. It would puff very little smoke out of that hole, but you could hear it when standing behind the bike.

IP sez Texas.

06-22-2009, 08:47 AM	#1
BikeRider12345 Registered Member Join Date: Jun 2009 Posts: 6	Noise out of the muffler I have a 1980 Honda CB750K. It starts right up, but it sounds like air is escaping from the mufflers every once and awhile. What could that be from?

06-22-2009, 08:56 AM	#2
pushrod Founding Member Join Date: Nov 2001 Location: Baja 'Bama Posts: 3,478	Assuming you don't mean the air is coming out of the back, where do you think the 'leak' is? At the head, midbody, joint(s), etc. __________________ You would not understand, this is not how I am... I have become - Comfortably Numb.

06-22-2009, 11:12 AM	#4
MOKE1K Registered Member Join Date: Jul 2008 Location: Kalapana, Big Island Posts: 3,956	Ah, ahem,...I am lost? __________________ "YOU CAN'T BOLT ON SKILL" "The only thing limiting your bike, is you" We survived Bush you'll survive Obama! "the most fundamental fact about the ideas of the political left is that they do not work. therefore we should not be surprised to find the left concentrated in institutions where ideas do not have to work in order to survive." --thomas sowell

06-22-2009, 12:55 PM	#7
mscuddy MODERATOR X Join Date: Jun 2007 Location: Next to my still checkin the temp. Posts: 5,444	Buy a Kerker reproduciton for anout $150.00. The "F" model had that big goofy pipe on it that had more crap in it than my roll-a-way filled with jig saw puzzles. Not only will it perform better, you'll get that 70 lb. salami off the left side and it will handle better too. Face it, your 25 plus old exhaust pipe has more holes in it than Bill Clinton's tenor sax. It might sound better but that's the price we pay sometimes. __________________ A gun is a tool, Marian; no better or no worse than any other tool: an axe, a shovel or anything. A gun is as good or as bad as the man using it. Remember that.

06-22-2009, 02:28 PM	#8
acecycleins Founding Member Join Date: Jun 2007 Location: North Georgia Posts: 4,125	Is this KP messing with you guys. What is a motor- an air compressor with a purpose. Air, fuel, ignition- throttle and so it goes. Check the seating at the motor at the header. I used to have a old Bonni that had a crack at the top of the pipe. It would puff very little smoke out of that hole, but you could hear it when standing behind the bike. __________________ "Slack" - a state of being in which everything flows smoothly.....a frame of mind so at ease that the universe naturally cooperates.

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06-22-2009, 10:04 AM	#3
BikeRider12345 Registered Member Join Date: Jun 2009 Posts: 6	It is coming out of the back of the muffler. I should have been more specific. It comes in short bursts, it sounds like an air compressor going off. Just happens every 15 seconds or so. Is it a carb timing issue?

06-22-2009, 11:55 AM	#5
BikeRider12345 Registered Member Join Date: Jun 2009 Posts: 6	When the bike is running, I will here a noise come out of the muffler about every 15 seconds that sounds like an air compressor. Just like a burst of air. That is the best I can explain it. Not a normal sound for an exhaust. I am just wondering if it is a synching issue or what. I think it is only the left muffler.

06-22-2009, 03:42 PM	#9
MOKE1K Registered Member Join Date: Jul 2008 Location: Kalapana, Big Island Posts: 3,956	I Know Its Your Muffler Bearings!!! __________________ "YOU CAN'T BOLT ON SKILL" "The only thing limiting your bike, is you" We survived Bush you'll survive Obama! "the most fundamental fact about the ideas of the political left is that they do not work. therefore we should not be surprised to find the left concentrated in institutions where ideas do not have to work in order to survive." --thomas sowell