knocking noise

[DualSportDad]

I just bought a 2006 Uly yesterday and took it out for a 200+ mile ride today and noticed a knocking noise between 2500 and 3000 rpm with light throttle in gear. More or less gas and the noise goes away, not quieter, gone. Its not a tapping noise, it sounds like a lower end knock.

I'm just wondering if this is normal as I've never owned a 12 motor before and my 9 did not make this noise.

My 06 Uly has 11,000 miles last 4 of Vin 0516 and has been owned by a 70 year old man since new and serviced at the Harley dealer.

[Theycallmecrash]

I say normal, and its very noticable with a air box delete or modifying the air box. Drives you insane if you are high.

[DualSportDad]

The knocking noise can be amplified by modifying the air box? How does that come about?

[DualSportDad]

So after reading a lot and seeing a bunch of threads mention the primary being out of adjustment and causing noise I decided to check it. It was way loose. When I rest drove this bike it also shifted much smoother than when I picked it up.

Here's a video of the slack I have now. It seems to be around 1/2 inch. Seem good?
Xb12x primary adjustment: http://youtu.be/L0H_zG5W1AI

[Theycallmecrash]

Cause the intake is right under your head, the pulses of the engine shoot straight up into your face, sounding like a knock. Modifying the inner air box takes away its muffling affect.... I think. Im no scientist just my thoughts on it.

[DualSportDad]

I'll have to check to see if it's been modified. Only thing I see different is a ebr front rotor and hh pads front and rear. But who knows. I checked for a race PCM and it's stock.

[fishxb12]

I changed my airbox back for that reason. I couldnt get over the loud thumping coming out of it.

[DualSportDad]

the noise i'm hearing is some sort of knocking noise, it's not coming from the air box for sure. what are the first signs of crank failure? anyone have a video or sound clip of the first signs? i know i'm being paranoid here but that's how i roll. i'm almost thinking about selling the bike already and either offering my buddy that bought my lightning from me for me to buy it back or for me to go find a 08+ lightning SS.

[Theycallmecrash]

Its hard to determine any noise on a Buell.

[DualSportDad]

eh, i'm a bit freaked out because of the noise, i think it's off to craigslist she goes. shame cause she's clean as ****. just riding it 200 miles today it was super uncomfortable for me compared to my lightning as well. i was really looking forward to this bike working out.

[DualSportDad]

i rode her around a bit tonight with my buddy that bought my xb9sx. i noticed that the "knocking" noise is more like a clanging noise and it doesn't change frequency as the rpms change so i'm just going to chalk it up to somethings rattling and i don't know what. if she blows i'll buy a 9 motor and swap it in.

now wtf can i do about this seat.... and all this heat coming out of the right side? do all 12's have this much heat?

[user_deleted]

do all 12's have this much heat?

all ulys do. lightning longs a close 2nd.

[UMDterp13]

WAIT! The noise is the horn hitting the front fairing. All mine do it too. 2000-2500rpm is perfect vibration for horn to move. Stick some felt or soft material on the horn or back side of front fairing and I bet it stops. Or bend the horn back a little.
Hope I'm right or I'll feel sad...

[DualSportDad]

Where is the horn... Behind the fairing?