Perfect Circles, Perfect Spheres

They say something is happening, but you don’t know what it is….

Do you, Mr. Jones?

I’d been having an extended motorcycling Mr. Jones moment.

My K1200LT had been displaying this odd symptom, which only manifested itself when the bike was being operated in stop and go traffic — at or below a walking pace.

Now normally, I make extraordinary efforts not to ever operate this motorcycle at anything short of Warp 3, but reality sometime has a way of intruding.

On a recent trip, I’d gotten stuck in an unspeakable Interstate Highway backup, which had me riding the clutch and walking the bike along for the better part of three hours. I’d noted the odd behavior previously, but it hadn’t really been intrusive and was not detectable at speed.

What the bike had been doing was sending this odd sensation through the bars at under a mile an hour — it felt, for all the world like somebody plucking the high G string on a bass guitar — a little ‘Boing’ would be sent through the bars.

I’ll freely admit being a little obsessive over the operating condition of my machinery. If you think about well more than 1000 lbs of bike and rider in an 80 mile an hour corner being managed by that wheel, you’d be obsessive too.

I mentally went through the list of things I thought it could be. The folks at Fredericktown Yamaha — that have made a cottage industry of mounting and balancing the many tires I consume — had previously called my attention to what they thought was a slight wave in the rim likely created by a DC pothole.

“Keep an eye on that”, they told me, “If you start getting abnormal wear in that spot you’ll need to repair or replace the wheel.”

Only somebody that worked in a Yamaha shop would ever suggest that one should replace an OEM BMW forged wheel.

I have purchased running motorcycles for less than the MSRP of that wheel.

Anyway.

That rim was a possible cause. The bike’s original front wheel bearings — at 92,000 miles — was also remotely possible. And there were a few possible maladies of the front brake system — transfer of pad material to a rotor, or a rotor gone subtly potato chip shaped – that might also cause this weird pulsation. The bike was rock solid under heavy braking, though, so that seemed remote.

I obsessed about it. I had the bike at least half a dozen times up on my trolley jack — front wheel hanging up in the air, spinning it by hand — looking for run out in the rims and rotors — feeeeeeling the bearings, feeling the brake drag.

I had lots of ideas.

I had no pattern I could discern.

 

***

 

So I took the bike off the road.

I ordered a new front tire, as mine was well worn. I ordered a front bearing and seal set. And set about to find a reputable wheelsmith.

 

***

 

Fortunately, the District of Columbia contains a volatile mix of really unspeakable paved driving surfaces combined with folks that have a compulsive need to spend incomprehensible amounts of money to make people look at… their cars. When a new wheel for your Lamborghini costs more than my K1200LT, people will figure out ways to fix them.

TAS Wheel and Machine appeared to be those guys. Their online reputation — Google ratings, Yelp reviews — was 5 stars all the way. They specialized in automotive exotica, but went well out of their way to make sure folks knew that they were comfortable and qualified to work on motorcycle wheels as well. They had positive feedback from both racers and Harley riders, both of whom have been known to be particular.

So I called them, and asked if they’d be willing to work on mine. They were.

I asked a few questions about their process, and what kind of levels of accuracy they were shooting for and were usually able to achieve. The numbers they provided were right in line with or slightly better than the BMW spec. They were also able to check the run-out on my disk rotors as well.

So I resolved to pull the wheel, and to set everything up front straight.

 

***

 

So of course, Finn’s Buell Blast decided, as it had several times before, that Today Was A Good Day to Die.

It seems, that in their choice of materials, the Buell Men had not blessed The Blast with the highest specifications. The steel used in its exhaust header, for example, could not deal with the thermal stress of being operated in heavy rain — which, of course Finn had done with startling regularity. Blasts abused in this unfeeling and unkind manner all protested by turning their headpipes into loosely amalgamated but unconnected steel fragments — with predictable effects on their drivability and throttle response.

I find it difficult to explain, but in motorcycles, as in human medicine, there are protocols for triage and care.

And a motorcycle that will not run is entitled to care before a motorcycle that will run, however badly. A corollary of that principle is that one should never electively start to disassemble another motorcycle for service when one is already apart. It’s probably more of an irrational superstition, but having parts of multiple disassembled motorcycles sharing the same workbench gives me the willies. This irrational fear is probably protecting me from continuing to buy more old motorcycles, so I’ve become rather fond of it.

So while Finn’s Single sat in the shop with the stock exhaust stripped off, a rag stuffed in its exhaust port, and an aftermarket exhaust system and a pile of carburetor parts headed inbound somewhere in the UPS system, my LT just sat in the Doctor’s waiting room, reading a complimentary bad magazine, and waited to be the next patient under care.

 

***

 

When, after the passage of some time, The Blast brapped down the driveway, having found a few brand new operating characteristics, it was time to return to my problem at hand.

I got the bike up on the jack, pulled the front wheel, threw it my truck and headed for Laurel.

 

***

 

While halfway across the parking lot at TAS, I was greeted by Brett, one of the two brothers that run the shop, who offered to take the wheel from me with a work-gloved hand. While I normally neither expect nor receive this kind of white-glove service, I didn’t feel right rejecting the kind offer of assistance, especially given I had the new tire in my other hand.

Once inside the shop — which was well lit, open, organized and neat enough to serve as a TV cooking show’s working kitchen — Brett introduced me to his brother Brody, who immediately set about grabbing a wheel balancing stand to triage my Bavarian patient. While he was jigging the wheel into the stand, I spent a little time gawking. In the business end of the shop, on a truing stand was the largest Performance Machine chromed Torque front motorcycle wheel I have ever seen — it was at least a 23 inch rim and maybe bigger. These day’s ‘Big Wheel’ Customs are all the rage around DC, although there are apparently no rough surface benefits to running such a large tire size, despite what your dirt bike buds and physics class may have told you.

With a few turns and a dial gauge Brody confirmed the existence of the slight wave that had offended the guys at Fredericktown. But as he looked at the tire itself, he frowned.

“Look at this”, he said. “That bulge and divot? You definitely had a belt shift or fail in this tire’s carcass. Scary.”

Once again, I proved to be not half as smart as I thinked I was.

During all the consternation and obsession over hard parts, I’d completely overlooked a much simpler explanation.

The tire.

D’oh!

Anyway, after making some biker small talk — showing off two wheeled baby pictures and such — I filled out a work order which authorized the guys to straighten the wheel, and to repaint it if they thought it necessary. As they worked with a lot of BMW automobile wheels, which are nearly identical in construction and even the spoke pattern, they already knew the drill and had the proper Wurth wheel paint to perform the service.

All in all, Brett and Brody struck me as the most pleasant, professional and competent guys I’ve had the pleasure to do business with in quite some time.

It was time to get back in the pickup and head home to wait for their call.

 

***

 

Back in the shop, I had my Motion Pro bearing removal tool, my heat gun, and my hammer at the ready, while the bearing sets rested comfortably in my freezer. I considered labelling them with a Post-It Note reading “Do Not Eat”, but concluded it probably wasn’t necessary.

I did take one of my small brass calipers to check the brake pads while everything was apart. My SBS organic pads — which come out of the package with 5mm of friction material, still had a solid 3mms remaining, so they would last through another front tire and could be reused.

The TAS Men checked in about 4 days later to ask when I could swing by to pick up the wheel. I was busy at work, but Sweet Doris From Baltimore was bored that day, so was happy to take a trip in her truck to Laurel.

After work that day, I went back into the shop, and pulled the wheel’s grease seal, and used my snap ring pliers to remove the substantial snap ring that held the wider of the two bearings in place. I took a few pictures of the hub so I had clear photos of how deep the bearings sat in the hub.

Then I took collet and driver in hand, and, after having blown some heat into the wheel hub, removed both bearing sets and the spacer which sits between them. It was a little fiddly to get the collet solidly installed in the bearing’s inner races solidly enough to drive them out, but after a few tries the bearings hit the top of the steel workbench with a satisfying thud.

After cleaning up the hub’s interior, I heated the hub again and grabbed my hammer, a 1 1/4″ socket, and the larger of the two bearings out of the freezer.

If you’re wondering why I was keeping BMW wheel bearing sets in with the frozen dairy treats, it’s because the wheel bearings are an interference fit, and combining a hot (expanded) hub bore with a cold (contracted) bearing makes the process of fitting the bearing far less difficult.

I dropped the bearing into the bore, applied a little hammer, and watched as the bearing moved down towards it’s seat. I understood that when the bearing seated one would be able to hear the high pitched ringing changed to a deeper thunk when the bearing seated. Being not entirely sure my ding had thudded, I gave it one more strike just to make sure.

In retrospect, that last hit was ill advised.

As I pulled the driver our of the bore, the bearing’s seal popped loose, trailing lube.

That bearing was toast.

Some folks enjoy salty language. If you are one of these people, for whom expletives serve a stress reducing purpose, feel free to supply your favorites and I’ll enjoy their benefits by proxy.

Me, though, I just felt very small, and resigned myself to a fast recovery from my own lack of skills, and a few more days without use of my motorcycle.

 

***

 

Upon close inspection, the problem was pretty obvious. My socket — a normal 1/2 drive — was a thinwall, that was just a tad too small to make solid contact with the bearing’s outer race. An impact socket, with thicker walls, would have been perfect.

My choice was to admit defeat, and seek professional help to complete the job, or take a gut check, and prove that I was smarter than aluminum.

After a few permissible moments of depression, I began to think that maybe, just maybe, I was smarter than aluminum.

I went back to Amazon, found a single replacement bearing, and another addition to my suddenly growing collection of Motion Pro motorcycle tools — this one a motorcycle bearing driver kit.

Finn has a thing for stickers — he’s hoping to completely cover the outer surface of his electric bass case — and between All Balls and Motion Pro, this job was really working out for him.

 

***

 

The next day, the bearing driver showed up in the mailbox. My confidence rebounded — the tool was clearly well made, and allowed me to match outer face drivers to correctly sized and interchangeable inner race alignment collets. With this tool, there was no drama about the ability to correctly install these bearings.

The bearing though, was proving to be a tad trickier. The major Los Angeles-based bearing house had, despite having said the bearings were in stock, cancelled my order upon discovering they weren’t.

Having struck out getting the bearing, I swallowed more pride and called All Balls Racing, whose web site said they were not shipping orders this week because they were moving the business.

Surprisingly, a Customer Service Agent picked up their extension on the second ring. I gave here my order number and described what had occurred.

“This is NOT a warranty request. The product was fine. I am an idiot and I broke it. It is MY fault. I just want to purchase the single bearing from the kit rather than the entire kit.”

The CSR at All Balls basically thanked me for being an honest idiot, and then goodwilled me a warranty replacement over my protestations.

The bearing was in my mailbox at lunchtime the next day.

 

***

 

My second attempt — armed with the proper tools and the knowledge born of the wrong kind of experience — went far more smoothly.

Ten minutes of heat gun and hammer later, the wheel had new bearings and seals correctly installed.

 

***

 

A few hot sweaty minutes later, the wheel was back on the bike, and the brake calipers and fender reinstalled.

I rolled the bike down the driveway and rode at walking pace to both ends of the block and then headed back into the driveway. The LT was rolling smooth, with no sign of the former low speed symptoms.

I went inside to grab a jacket and helmet, and see if Finn wanted to go for a ride.

 

***

 

Trying to keep a K1200LT and a Buell Blast together on the road takes a little effort. Thinking of the LT as if it had a three speed transmission helps make that a little easier.

As we headed down MD 383 out towards Burkettsville, my motorcycle had been transformed. Any any speed between zero and sixty miles per hour, the front end of the LT was glass smooth — the vibration was utterly gone, the front end suspension seemed more settled and was clearly tracking the pavement more accurately, and as I transitioned the bike from side to side, the transition from one side of the tire to the other was dead rigid, rock solid.

A few brief blasts up to higher speeds felt dead planted and utterly stable. A few hard braking tests were rock solid with no pulsation whatsoever.

Perfectly round rims and round tires combined with perfectly spherical bearings made this bike ride like a two wheeled version of a big Mercedes Benz — feeling like it was carved from a single piece of alloy, compliant, comfortable, and like it would willingly do anything the rider asked of it, for as long as that rider might want to ask it.

For the next hour or so, Finn and I criss-crossed The Valley, trying to keep away from the pop-up thunderstorms that were coming in from the west, and enjoying our newly repaired steeds. The new authority of the Blast’s exhaust note — courtesy of the recently installed Jardine exhaust — allowed me to keep track of Finn’s position on the road behind me by ear — was something I found strangely comforting.

Keeping my eye on him in the rearview continued to demonstrate his comfort and competence in the corners — he never put a wheel out of place.

We finally came back to the shop, having never encountered any of the rain out on the road.

“Good ride, Snorky?”

Great ride, Pop.”

Perfect.

 

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