my 2009 FLHTP (103 cu. in.) makes a rattle that sounds like it is coming from the front rocker box, but I can't be sure at all.

(for one thing, my hearing is about shot to hell) - it almost sounds like something rattling, but its brief, only making the noise when I first roll back on the throttle.

I thought maybe it was just engine ping, but I use 91 octane (highest around here) and rans 6 ozs of Seafoam through the tank with no real change.

does anyone have any thoughts? I don't know a lot about what is in the rocker box, but I'm not against finding out if thats the problem...

thanks

 

Top motor mount ?

 

Just checked the top motor mount and its tight - thanks for the suggestion though Captain

 

My first thought is the same as yours, OP. Try a bottle of octane boost instead of the seafoam.

 

If it only does it on hard accel, I think it is a timing issue rather than octane. The timing is advanced too far and needs to be retarded in those power bands.

Bwana

 

My guess would be the compensator. I changed mine yesterday for the SE version. Major reduction in perceived engine noise.

 

did ya check the bottom motor mount. my bike did the same thing thought it was the top and it turned out o be the bottom one.

 

Run excellerating by encarta and maybe that will give you a clue....

 

thanks guys, a few more things for me to check out/consider.
I'm not sure if I understand how the compensator affects this rattle tho - can you expand on that a little?

I do have Fuel Moto stage one & PCV on the bike, by the way.

 

fyi...the compensator nut does not ping or rattle, it knocks.

Bwana