High speed wobble

Since we started on our trip Diane’s bike has been experience a wooble right around 70mph. Very disconcerting and dangerous. This wooble did not manifest itself before so our suspicion was it was either related to the panniers or the additional weight on the bike or both. We tried offloading weight from Diane’s bike (I strapped the tent roll to mine) as well as moving her waterproof duffle bag from the higher tail platform directly to the seat in order to improve both the aerodynamics as well as lower the center of gravity. No change in behavior. I verified and slightly modified the tire pressure to meet the suggested values in the owners manual. No change in behavior. Crap.
In order to test if it’s the panniers, I took the bike out for a run (empty panniers) early in the morning on US 54 heading towards El Paso – our hotel was close to the intersection where US 54 comes into Alamogordo. Based on some quick googling I wanted to test two things: (1) Did the bike run ‘true’, i.e. at low speeds with the hands off the handlebar did it keep going straight or did it veer to the side and (2) behavior at 70mph with only the panniers on the bike. With regard to (1) I thought I detected a slight veer to the right, for (2) mostly steady with just the slightest hint of a ‘shimmy’, barely noticeable, could also have been my imagination ;-). I forgot to mention that we had already tested the steering head bearings – no play in the fork.

The good news was that the panniers were (most likely) not the culprit. The bad news was we still hadn’t fixed the wobble. While looking the bike over, checking for loose screws and the like I noticed that the left and right side notches used for keeping the rear axel straight when adjusting the chain tension were not lined up exactly. This difference was seemingly minor. Hmmm. I remembered reading that if the front and rear wheel don’t line up properly this can lead to a wobble. OK. I can tackle that one, I break out my tool pouch and look for a socket that will fit the axel nut. I start with 17mm, no; 19mm no. What, no more sockets?!??! That cannot be. Did I forget to pack a socket for such a basic maintenance activity? I’m mad at myself at this point. Cannot be. Double crap.

We saw a Lowe’s on our way into Alamogordo which is probably our best bet to find some tools. First I buy the 21mm socket. No, still too small. Back it goes. Rather than trying them all individually I get a 23,24 and 26mm socket. The 24mm fits. By this time it was getting warm so we pull the bikes into the fleeting shade in front of the Lowe’s and I proceed to adjust the chain, or rather loosen the axel nut so I can make sure the notch readings are the same on both sides.

This was the second occasion of the trip where a complete stranger stopped by and asked me if I needed any help or any tools! The kindness of strangers.

About halfway through adjusting the chain/notches I notice this big socket in my toolkit. Hey, where did that come from? Can’t be! Sure enough, a 24mm. How could I have missed that? Simple, the tool pouch has closable pockets which I used to store the sockets. Unfortunately, the 24mm was too big to fit but it fit in between two pockets. Perfect! A victim of my own packing. Too funny. I now have a second 24mm socket ;-).

Diane’s side note on the ‘kindness of strangers’: while working on the bike, another rider drove up and parked right next to us. He and his lady dressed to a T in her denim mini skirt, studded ankle boots and perfectly fixed hair (how did it stay that way?!?) got off their bike and walked right past us. Granted, they smiled and responded to our ‘hello’ but didn’t asked if all was okay. Yes, I know, not required, but still … it was a surprise given the other guy came from across the parking lot to check on us. I guess this couple was in a rush to get to their 4th of July celebrations. Okay, back to Oliver’s story …..

After the adjustment we head north on US 54. I ask Diane to slowly take the bike up to speed, traffic permitting. I follow closely behind to see if I could see a wobble. It looked pretty steady at 70/75mph to me. At the next stop Diane confirms it – no more wobble!! Yeah. A huge relief. The bike is steady as a rock. So, although the wheel alignment was only off by a bit, not noticeable when riding without luggage, it manifested itself with the additional weight on the bike.