09 FXDB Cornering Shake

Discussion in 'Dyna Models' started by Stevo4204, Aug 29, 2010.

  1. Stevo4204

    Stevo4204 Member

    My wife rides an 09 FXDB. This year, she has noticed that the front end has what she calls a "death shake" while cornering at speeds over 70 MPH.:( The bike handles great under all other riding conditions. Straight lining at 70+ creates no concerns. The bike has 20K, services are done at 2,500-3,000 miles. The stearing neck bearing is at factory torque specs, (old dirt bike racing habit), tires never get to the wear bars, pressure is 38 front, 40 rear. Prior to chasing a phantom and spending $$, I am looking for input on fork oils, fork springs and or fork braces that will eliminate the shake.
  2. HDDon

    HDDon Experienced Member Contributor Retired Moderators

    Have you tried doing the fall away test on the front end? I've seen several Dynas with front fork brace (like the ones we used to put on our MX bikes). I'm sure there will be more comments from the Dyna riders here on the forum. Have you made sure the rear wheel is alighned with the front?
  3. Hoople

    Hoople Account Removed

    Here are a few things I would also check.

    1) Since the bike has 20K on it, the rear axle has been removed and it is out of alignment. The rear wheel center-line is Not in parallel to the front wheel center-line. See rear wheel hollow axle alignment posts and threads.

    2) Stabilizer link under tank has bushing play, or is not adjusted to correct length. Check to see that the front & rear brake rotors are in the same vertical plane.

    3) It's True-Track Time!

    True-Track, Inc.
    Last edited by a moderator: Aug 29, 2010
  4. TQuentin1

    TQuentin1 Well-Known Member Staff Member Moderator

    In addition to the great info Hoople provided above, I suggest that you change the fork oil. Follow the book to the letter, and after refilling the tubes with clean fluid, measure the air gap above the fluid to the top edge of the tube. Adjust so the they are equal within 1/8". This must be done with the bike absolutely level.

    Then remove the front wheel and inspect the front brake pads to ensure they are wearing evenly.

    Remount the front wheel "by-the-book" making sure to pay attention to the details.

    Follow Hoople's suggestions above to ensure that the front and rear wheels are travelling on the same line and pointing the same way. Check your turn buckles!

    Let us know.

  5. Jimmy_k

    Jimmy_k Member

    I had the fall away issue with my 07 Super Glide Custom (Love that bike...). It had a major clunk every time I hit any kind of bump in the road, but no shake like what's described here. I had to pick up a new 'hard' washer and re-do the fall away, and torqued down the nut much more than the original was with the old 'soft' washer. Wouldn't totally rule out a loose steering head, but the shake is probably something else.
  6. Stevo4204

    Stevo4204 Member

    Going to have the front tire checked first. The fall away is at factory specs. The bike handles well in all other circumstances. One step at a time. Will advise.
  7. murf

    murf Active Member

    I don't know what the manual says for "07 street bob. My '06 super glide manual said 30 psi frt and 36 psi rear for lone rider. maybe tire pressure is too much. ?
  8. Wonkaboy

    Wonkaboy Banned

    Every Harley i owned shaked around the corners !
  9. DynaBob09

    DynaBob09 Active Member

    Mine doesnt. Very solid .
  10. Stevo4204

    Stevo4204 Member

    Put a new rear tire on as it was close to the wear bars. Ran 34 lbs front, 36 lbs rear. Discovered that the local HD dealership whom told me that all Dynas handle this way had obviously not checked the axle alignment and neither had I to detailed specs. The rear tire was offset to the right while sitting on the bike. I aligned the axle and adjusted belt tension. Traveled 500 miles this past weekend and about 75% of the stearing wobble went away. Also noticed that the bike did not follow the Black Snakes in the pavement near as bad. Not done yet so will advise as to next find and cure.