Front Axle induced speed wobble

torch · Jun 23, 2023

Recently I have had a head shaker wobble if the handlebars are released at low speeds -- no problems at highway speed, no problems with at least one hand on the bars, but an increasingly violent head shake if both hands are removed. I checked all the fork alignment and adjusted the steering head torque with no difference. I attributed it to the worn tire which is approaching the end of it's serviceable life and started shopping for new shoes. I didn't remove the wheel and check the balance because there seemed little point if I'm changing the tire soon -- I'll balance things with the new rubber.

Then the other day I was washing the bugs off and I noticed one of the left front axle pinch bolt heads was sticking out slightly -- it was loose. It's partner was barely finger tight. On the right side, one bolt was missing and the other barely more than finger tight. I replaced the missing one and torqued everything down and whadayaknow: the wobble is gone.

I can't say that I've seen this mentioned before in the multitude of wobble threads, so add that to the list of suspects: check the torque on the axle pinch bolts.

RossKean · Jun 23, 2023

I haven't seen this before. I am pretty careful about torquing front pinch bolts using the sequence and repeats as specified in the FSM.

Something to keep in mind.

Whooshka · Jun 23, 2023

The OP needs to ask himself why were those pinch bolts missing and loose?

torch · Jun 24, 2023

Whooshka said:
The OP needs to ask himself why were those pinch bolts missing and loose?

I can only assume I forgot to torque them when I reinstalled the wheel. I remember the day quite clearly, and will do so until the end of days -- May 20, 2022. I was prepping the bike for my brother. He could barely walk, but was determined to get one last ride in while he could still sit upright.

I may have been distracted.

harper · Jun 24, 2023

I once noticed that one of the bolts holding the right front brake caliper on my '06 was missing. I have no clue how it could have happened. I bought a metric bolt at ACE hardware that I installed until I could get one of the correct, vented type. I also had a screw come out of my left highway peg plate. No big deal but again another WTF moment.

Whooshka · Jun 24, 2023

torch said:
I can only assume I forgot to torque them when I reinstalled the wheel. I remember the day quite clearly, and will do so until the end of days -- May 20, 2022. I was prepping the bike for my brother. He could barely walk, but was determined to get one last ride in while he could still sit upright.

I may have been distracted.

Very sorry to hear about your brother. Very commendable of you to get him on a ride.

Lesson learned I'm sure. Good thing nothing "majorly bad" happened.