Need Help to ID Strange Engine Noise
Cruiser
Joined: Dec 2008
Posts: 225
Likes: 6
Mine has done the same thing. I posted about it last year and a few people have heard it. I've never heard my bike ping while driving it but you can't miss that loud metallic crack when it happens. Never did hear what the cause was.
Both of my 103 touring bikes have done this. It happens when the bike has been idling for a bit (like at a stop light) and just before you gently take off you crack the throttle 'just a blip'.
CRACK - there's that metallic ping that sounds like you just chipped a front piston.
It's detonation. A hot spot on the piston or cylinder head / valve that ignites the burst of fuel before the spark. The engine tries - just for a split second - to run backwards.
Most folks don't seem to recognise it, just assuming it's normal. I freakin' cringe every time it happens.
EDIT - For the sake of the engineers out here, it also happens when a piston '*****' sideways due to a hotspot igniting the fuel / air load unevenly, causing the piston skirt to contact the bore.
CRACK - there's that metallic ping that sounds like you just chipped a front piston.
It's detonation. A hot spot on the piston or cylinder head / valve that ignites the burst of fuel before the spark. The engine tries - just for a split second - to run backwards.
Most folks don't seem to recognise it, just assuming it's normal. I freakin' cringe every time it happens.
EDIT - For the sake of the engineers out here, it also happens when a piston '*****' sideways due to a hotspot igniting the fuel / air load unevenly, causing the piston skirt to contact the bore.
Last edited by Ultra103; Nov 4, 2013 at 09:54 PM.
Ultimate HDF Member
Joined: Dec 2010
Posts: 7,776
Likes: 2,252
From: wet coast BC
2011 to present have the SE comp installed. This noise was related to the old stock comp not saying it is comp noise, just that less possible on low miles.
some have said it occurs when blipping at hot idle. has anyone had a friend blip while listening with stethoscope.
some have said it occurs when blipping at hot idle. has anyone had a friend blip while listening with stethoscope.
Mine's a 2012. Happened many times.
Cruiser
Joined: Dec 2008
Posts: 225
Likes: 6
If that thing went off while you had the stethoscope to it you'd blow your eardrums out. If you whacked the front cylinder fins with one of those small ball peen hammers it would be the same.
Ultimate HDF Member
Joined: Dec 2010
Posts: 7,776
Likes: 2,252
From: wet coast BC
so what is the right way
Cruiser
Joined: Dec 2008
Posts: 225
Likes: 6
Maybe data logging with the powervision would show a knock event but I can't bring myself to cause the noise on purpose. Mine only did it one time this season and I wasn't logging then. My bike is in hibernation now though.
zen;....
Did you ever figure out what was going on...? Bought my 2012 back in October and have only put about 2000 miles on it because of the weather but I rode today and when I was parking it back in the shop....blipped the throttle to get into neutral and that is when I heard it..First time and is definitely not ping>>>>>
Did you ever figure out what was going on...? Bought my 2012 back in October and have only put about 2000 miles on it because of the weather but I rode today and when I was parking it back in the shop....blipped the throttle to get into neutral and that is when I heard it..First time and is definitely not ping>>>>>
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Road Warrior
Joined: Apr 2010
Posts: 1,648
Likes: 37
From: Monroe, Louisiana
Sounds like the compensator doing what it is suppose to. The cause of the kick back is likely too lean at idle, causing the kickback. Had a 2010 Limited and it did it bad when new. After putting tuner on it it didn't do it anymore.
Seasoned HDF Member
Joined: Jan 2006
Posts: 11,476
Likes: 3,003
From: Charleston, SC
My money is on "Pinging" which nearly all stock bikes do it when hot - unless it's been tuned. Needs to have a little gas added to the 1000-1500 or so RPMs at 0% throttle and a wee bit added the 2-5% throttle.
Last edited by lp; Jan 30, 2015 at 05:51 AM.