Tips for finding exhaust air leaks?
Tips for finding exhaust air leaks?
I am chasing (I think) an air leak that is causing some decel popping and an occasional after fire pop when changing gears at higher RPM's.
Does anyone have any tricks that help in finding leaks with the bike sitting at idle or with partial no-load throttle?
I was thinking maybe applying some (unlit) acetylene gas or oxygen from a torch, or spraying something flammable (WD40?) around the joints. I tried smoke from a cigarette but there was too much air moving to be effective.
Thanks.
Does anyone have any tricks that help in finding leaks with the bike sitting at idle or with partial no-load throttle?
I was thinking maybe applying some (unlit) acetylene gas or oxygen from a torch, or spraying something flammable (WD40?) around the joints. I tried smoke from a cigarette but there was too much air moving to be effective.
Thanks.
Road Master
Joined: Nov 2009
Posts: 997
Likes: 3
From: Charlotte, N.C.
You could use propane around the intake but I found this hard to do since the throttle body is very short and the intake may pull some of the propane into the air cleaner making the idle increase. On the exhaust a mechanics stethoscope works perfect. You could also use this on the intake side as well listening for a "hisssss" sound.
Here is a link:
http://www.harborfreight.com/mechani...ope-41966.html
Here is a link:
http://www.harborfreight.com/mechani...ope-41966.html
Cruiser
Joined: May 2010
Posts: 172
Likes: 0
From: West Point, VA
I've been told by a few wrenches that they tend to feel for them with their hands, on a COLD bike. If there's a leak at a joint (jug flange, header/muffler, O2 sensor), feeling for the air escaping seems to work.
Obviously, there's a finite window of time in which this method will work. Hot pipes and bare skin don't go together well...
Obviously, there's a finite window of time in which this method will work. Hot pipes and bare skin don't go together well...
Cruiser
Joined: May 2010
Posts: 172
Likes: 0
From: West Point, VA
Visual inspection of the joints might show some evidence too. Black sooty streaks, and the like.
I've heard of using a feather as well. More in line with the kleenex technique, and maybe less susceptible to ambient air currents as the smoke.
I've heard of using a feather as well. More in line with the kleenex technique, and maybe less susceptible to ambient air currents as the smoke.
Road Captain
Joined: Oct 2010
Posts: 747
Likes: 7
From: NY
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I have used a barbecue lighter around the exhaust flanges. If the flame is fairly still you are good, if it draws towards or pushes away from the exhaust port with the engine pulses you have a leak.
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Road Captain
Joined: May 2012
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From: Bel Air, MD
I am chasing (I think) an air leak that is causing some decel popping and an occasional after fire pop when changing gears at higher RPM's.
Does anyone have any tricks that help in finding leaks with the bike sitting at idle or with partial no-load throttle?
I was thinking maybe applying some (unlit) acetylene gas or oxygen from a torch, or spraying something flammable (WD40?) around the joints. I tried smoke from a cigarette but there was too much air moving to be effective.
Thanks.
Does anyone have any tricks that help in finding leaks with the bike sitting at idle or with partial no-load throttle?
I was thinking maybe applying some (unlit) acetylene gas or oxygen from a torch, or spraying something flammable (WD40?) around the joints. I tried smoke from a cigarette but there was too much air moving to be effective.
Thanks.
Last edited by 2ropes; Aug 2, 2013 at 05:47 PM. Reason: check Harbor for the stethoscope