Dyna Clunk

[glider.]

Posted by "jmpancoast"...

Lots of problems with the 06 and 07s and steering head bearing adjustment and torque. So much so, there is a service bulletin out related to it. The bulletin recommends a new washer and new torque specs.

Be forewarned. A lot of people, including service techs, will try to fix the "front end clunk" by simply tightening the steering head nut. This is not the correct way to do it.

The upper triple tree (or clamp) pinch bolts need to be loosened. Under the upper tree is an adjustment nut. Tightening of this adjustment nut is what puts pressure on the steering head bearings. The upper nut is then torqued to squeeze the upper tree against the adjustment nut. The torque specs just keep everything together. Don't let the dealer shortcut your repair.

Here is a copy of the service bulletin:

 

[FLDL02]

I'm not a forum member but I have read many threads regarding Dyna clunk and softail clunk because I had one on my 02 FXDL with a FX softail front end installed. I thought the clunk was a steering stem issue as well. On fork extensions over small bumps like train tracks or manholes I got a metallic clunking sound. After trying to adjust fall away and torque on the steering stem I decided to investigate lower and disassembled my forks thinking the noise may be lower but translated up to the triple trees from below. I found that the "fork lower stop", a small aluminum cup like part that bolts onto the end of the fork tube damper was covering a fluid transfer hole on the damper. This prevented proper fork oil transfer during fork compression and extension resulting in the fork topping out too rapidly. The clunk was the sound of the damper meeting the rebound spring with too much force.
I cut 3mm off the top of the fork lower stop to uncover the damper tube hole and reassembled the bike. No more clunk.
I checked the HD dealership to see what fork lower stop they are selling for my front end and it is the same as I had. If it covers your damper tube hole then you will probably get the same clunk that I was getting. I also noticed that there are different size lower stops on different bikes. I hope this helps.