Rattle when Hard excellerating
Unofficial HDF Chaplain
Joined: Dec 2009
Posts: 21,128
Likes: 18,024
From: san diego
it must be spark knock (ping) might be due to higher engine temps that you are running along with too lean a mixture.sounds like you haven't messed with timing thru some kind of fi devise (sert,power comm.) you have changed your intake, that in itself can lean out the mixture to cause the ping, this is very bad, you have two flame fronts starting out and meeting somewhere in the middle of the piston causing that noise. thats where the piston is weakest, and have seen holes in them due to this noise. yours doesn't sound that severe, but I would go to someone that can investigate with CO machine/scanner equip to get that noise to go away, you might get your engine temps down in doing so
Road Master
Joined: Mar 2009
Posts: 962
Likes: 0
From: .....
This will probably sound goofy, but I had a very annoying rattle that occurred between 2800-3100 RPMs during hard acceleration. Of all things, it turned out to be that the nut on the back of the fuel door lock had come loose and was rattling at just the right RPMs; got lucky.
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Road Master
Joined: Oct 2009
Posts: 872
Likes: 0
From: Far (FAR) West Texas
This will probably sound goofy, but I had a very annoying rattle that occurred between 2800-3100 RPMs during hard acceleration. Of all things, it turned out to be that the nut on the back of the fuel door lock had come loose and was rattling at just the right RPMs; got lucky.
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Road Master
Joined: Oct 2009
Posts: 872
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From: Far (FAR) West Texas
I havent eliminated timing as a cause yet, but nothing's been done to alter that from where it was a couple weeks ago.
I have the Fuel Moto stage one, (put on 2 months ago), and the PCV put on at the same time as stage one. Emailed Jamie at Fuel Moto to see if the new map i installed a few weeks ago could cause this, and he said "The upper area will not have changes as the map was not revised there."
Last edited by deanp1964; Aug 9, 2010 at 11:16 AM.
Road Master
Joined: Mar 2009
Posts: 962
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From: .....
Ah but seriously, don't rule out loose or damaged mounts and fasteners. Do a mental review of any recent work, or events, that occured close to the time that the noise began and start checking and tightening there.
Also, I had a 07 Springer Classic and I let the service dude talk me into using SYN-3 in all 3 holes and man I had all kinds of noises and rattles then; it sounded like I was riding a big Singer sewing machine, especially under hard acceleration. I then switched out all 3 holes to different products and everything quieted down nicely. So I 'm just thinking out loud here, but maybe it's a lubrication related issue???
I really hope your problem isn't serious internal; hope it's an easy fix for ya.
Tourer
Joined: Jul 2007
Posts: 429
Likes: 0
From: Canal Fulton, Ohio
I have the same (i think) problem on my '06 fatboy. I have tried different gas stations, added octane boost, etc.. Dealer and Indy thought it was in the exhaust so I tightened the heat shields and pulled the baffles and put a little heat tape on the ends to dampen any rattle -but no luck. I agree it's annoying to not be able to find. I only hear it on acceleration after the engine warms up. I generally do not hear it when everything is cold.
If you find it ill be curious to know if that works for me.
If you find it ill be curious to know if that works for me.
Cruiser
Joined: Jan 2009
Posts: 155
Likes: 0
From: So. Calif.
Check with Fuel Moto, I had a similar noise when accelerating and under load changed my PCV Ignition map, all good.
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Road Master
Joined: Oct 2009
Posts: 872
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From: Far (FAR) West Texas
a little ride during my lunch hour today confirmed that the noise only exists after the bike is warm - and doesn't happen at all at idle or normal accelleration, only when rolling back hard on throttle.
Tourer
Joined: Aug 2008
Posts: 422
Likes: 0
From: Minnesota
I had the same problem and retarded the timing per Fuel Moto's suggestion in the PC-V map and the problem went away.