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need some help with motor trouble

madcatter

New Member
not sure where i should post this,first poost here.
heres the problem.i have a 09 ultra that has a knock from 2100-2700 rpm in every gear...now some stuff i looked at or did,cleaned air filter,changed plugs twice,opened primary thinking it coulda been something in there,checked the coil wires thinking it was a spark issue,been doing this for a few tanks of gas so its not bad fuel...theres no engine light on.no exhust leaks,belt is tensioned correctly....i got a stethoscope and went over lifter blocks,cam area,cylinder walls,heads,all sounded good,now i found the problem to be in the rear cylinder rocker box....now i never messed with these new motors,but was always into a shovelhead or panhead so i am not sure what i need to get ready for.i guess its first to take rocker cover off.
could i have a push rod outta adjustment and the lifter isnt building oil until after the rpm gain?the lifters have no noise at start up which tells me its good.
any help on where to look next?
 
Some other really smart members will help you out a lot more than I can, but I'll ask some questions to get things started.

1. You say 2100-2700 in all gears. What about the same RPM range in neutral with the bike not moving?

2. What's the most recent modification or maintenance that you did to the bike before you noticed the knocking?

3. Did you recently switch lubricants?
 
Is the 2100-2700 knock at steady throttle settings, under acceleration or both?
You say you have isolated it to the rear rocker box. The push rods are non adjustable, and a bent or loose one would cause problems/noise at more rpms.
Inside the rocker box is a lot like a pan or shovel, not hard to remove to take a look.
 
A bad lifter could cause noise in the upper rocker box, the stock lifters and push rods are not adjustable
 
Is there some sort of tuner or fueler on the bike?
 
the knock is not when its idleing-only under load of acceleration-but i located it with the stethescope while in idle so i guess it is,but not as noticable
it has a race tuner(screaming eagle)
stage one set up...
i have always ran either amsoil or mobil 1 v-twin synthetic oils and i never have missed any routine changes(3000 mile usually give or take a couple miles,and every third oil change i change tranny-shockproof stuff-and primary-formula1 stuff)
always run 93 octane fuel.been thru many tankful of fuel and its not improved.

i cant understand that its tune has changed,but possible.
 
That rpm range is right at the beginning of the torque band depending on cams. Going back to your stethoscope, check the bottom and sides of the engine case towards the back and then the front. Both sides, front, back and bottom (front and back). What you are listening for is a clicking (or worse clunking) sound that may indicate a problem with the connecting rods. This is not common, but members have discussed it here before. It is a bear to find!!

Cheers,

TQ
 
you can get an auto (or bike) ase mech book on amazon for < $20

octane ping

timing not tdc (same reason as octane, pre-detonation). timing chain ? (i think rockers roll on crankshaft for harley, unsure of new). rods may be hydraulic adjusted if not adjustable. blockage in hydraulics wrong oil ?

carbonized piston or upper head (dome) above piston. this reduces dedonation area and will cause poor burn, mileage, ping. pull plugs look for gunk.

be real CAREFUL diag with screwdriver to ear or stethascope it can fool you. it's all metal so sound will travel through whole bike and not always "straight" as you think - there are cavities and oil and such. (i had one mech diag a lower crank issue and found later the thud was on the front end steering pump !)

other guy had good idea

what rate (exactly) is the beat or ping: does it pick up as speed picks up ? does it hit once ever other power stroke ? every stroke ? 2x every stroke ? this could narrow down things quite a bit.
 
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