… and Dirt Under The Fingernails

Having one motorcycle away in someone else’s shop and another one in grimy bits all over the shop floor is just mentally destabilizing enough for me to render me certifiably insane.

Now under normal circumstances, I probably hover just underneath the threshold of being certifiable — think of it as ‘unofficially and tending towards insane’ — but having two of my three motorcycles rendered simultaneously non-functional is just enough to push the mental tach needle into the red zone.

These little technical challenges find me nervously and compulsively surfing motorcycle parts sites and Ebay, making useless trips into the garage to look at the patient and then return to the office shaking my head, and pulling out my old Clymer manual — which is now essentially an unbound collection of formerly bound pages — to check my memory of long mastered clearances and torque values.

Until all of my alloy mistresses are back together and returned to function, my sleep is fitful and hard to come by — serenity is nowhere to be found.

 

***

 

After more than a few days of waiting for George Mangicaro’s phone call, the phone finally rang. The next day Sweet Doris from Baltimore and I hopped in our Ford and rolled down the 60 plus miles of country road between us and George’s shop, Gridlock Motors.

Upon arrival at the shop, Darkside was sitting outside, minus the lower fairings I’d removed to get them out of the way before my abortive attempt at repairing the broken exhaust stud.

At the shop counter, George produced the other, more troublesome bit of the stud that had proved too much for my skills.

A Troublesome Stud (or what’s left of it)

“Yeah, this really turned into a pain to get out of there — we resorted to a Dremel mini-grinder to get the broken EZ-out broken up, and then had to use heat and drill clear through the other side of the stud to get enough purchase to remove it. You’d have never been able to get it out of there – it was welded in place and chewed up the threads coming out. I ended up having to Dremel away a bit of the bolt hole shoulder, and then put in a TimeSert thread repair insert — it will be plenty strong.

By the way — how long has your rear main seal been leaking?”

“Since 2011. Once I saw moisture show up at the back edge of the bell housing, I drilled the drain hole in the bottom of the case. I’ve never had a lick of problem with it since.”

“That’s funny. I’ll tell customers once they start leaking, they might get ten minutes out of it, and they might get ten years. Once I saw the drain hole, I wondered if I’d worked on this bike before – I didn’t think anyone else knew that trick.”

“All the older BMWs had an opening at the bottom of the bell housing to let any leaked oil escape. They didn’t really change the design of the rear main but they left out the drain. I just put back what they left out.”

George’s bill was more than reasonable – a little over 4 hours labor to remove and replace the exhaust system, remove and repair the failed stud, and to install the other seven studs and the new oxygen sensor I’d supplied. The parts bill for eight new style studs, new style stud nuts and the copper exhaust seals was less than $50.

“You know,” George told me, “it probably wasn’t your fault, pushing a cold engine too hard, that this stud failed. Notice that the new stud lengths are shorter than the original parts, and that the nuts are also smaller and lighter. BMW’s computer modelling software found that the old type longer studs and heavier bolts – would actually oscillate at high rpms. If it went on for long enough, eventually that oscillation would snap the studs in half, and that’s what happened to yours. The new ones will not do that.”

For a guy that had been feeling more than a little embarrassed, along with a few hundred bucks poorer, I felt a little better knowing that.

I pulled my ‘Stich, elkskin gauntlets and Shoei on, threw a leg over Darkside and chased Sweet D, who had left after dropping me off, back north towards Jefferson.

 

***

 

Back out on US15, I was pleasantly surprised to discover that the new Denso oxygen sensor had made a noticeable difference in both operating smoothness and throttle response. I was fairly gentle and measured in taking the bike through warm up — especially given the new thread repair. My experience with this bike is that the entire driveline doesn’t really reach full thermal equilibrium — with motor oil, gearbox oil, coolant and final drive oils at constant temperature – for nearly 100 miles. Traffic conditions, on a mid-afternoon in Faquier and Loudoun counties of Virginia, on a workday, aren’t really amenable to any kind of elevated pace anyway, so I tried to focus on maintaining some buffer from surrounding traffic, and just keeping things smooth and unstressed.

About 40 miles out of Opal, a few miles north of Haymarket and I-66, though, I got a look around the two tractor-trailer units I’d fallen in behind and saw broken yellow lines in my lane and at least 3/4th of a mile of open highway.

Failing to succumb to temptation has never been a problem I have.

Darkside had been loafing along at about 3400 rpm in fourth gear — I thumbed the turn signal, rolled the throttle wide open, pushed on the right grip and hit the passing beam switch twice. In less than a second, I was clear of the first tractor-trailer, and bathed in the Flying Brick’s signature intake shriek which was rising in intensity as the torque and acceleration continued to rise. I stayed in the throttle through the next second which saw me clearing the second truck. When the cab was a safe enough distance behind I gently began giving back some throttle and initiated a smooth roll back into my lane. As I shifted up into top gear I checked the speedo, which showed a speed well over the ton and a rate of acceleration that was only now gradually slowing. By my math a 55-110 split in about 3 seconds flat.

‘Sedate touring motorcycle’ my fuzzy Irish-Arab ass. Does anyone wonder why I love this motorcycle?

 

***

 

Back at the shop, I dropped both the motor oil and gearbox oil from their cases. Reviews of my maintenance logs showed that, as a result of time spent on the teardrop construction project  and the parade of OEM test bikes last year, that I’d only put a paltry 1500 miles on Darkside over more than 16 months since the last oil change. My logs showed motor oil that had aged out rather than failed on mileage.

My shame knows no bounds.

I completed the oil and gearbox service — changing the gearbox to a Valvoline 75-90 SynPower – and spent a few minutes replacing the lower fairings and bellypan.

During the road test the gearbox was shifting much better than the aged out conventional gear oil had permitted – shifts were faster, more positive.

I suspect that my near term working life will require me to be a great deal more mobile than my prior gig, which placed a premium on chaining me to my home office desk. At 19 years old and 95,000 miles on the clocks, this Flying Brick is ready to take me absolutely anywhere.

 

***

 

Now we were two up, one to go.

My replacement seal for the leaking ignition cam and the points, seal puller and replacement allen head hardware had arrived, so it was time to dive back in to getting the /5 back together.

I set up out in the garage and discovered the seal that had failed was actually loose in the seal bore – poking at it tentatively with one of my dental picks had it rocking visibly. Heat and time, it seems, had caused the material to shrink to the point where it was no longer effective. Even without heating the cases, the new Lisle Seal puller had the old seal in my hand in a flash.

When I went to clean up the points plate in preparation to reinstall it, though, it quickly became clear I had another problem.

My two airhead BMWs run a weirdo ignition setup that was a transitional technology between points and a full electronic ignition — the Dyna Ignition Booster. The Dyna setup is almost identical to their aftermarket electronic ignition except for one small detail. Where the full electronic units use a Hall Effect sensor to trigger the spark, the Boosters use the original points to trigger it. These units — which were common when these bikes weren’t museum pieces — have two benefits. The first is that the Hall Effect sensors are the most failure prone component of their electronic systems. The second is that in the event of a failure, the bike can easily be returned to stock points operation with the swap of two wires. Between my two airheads, these systems have provided hot, reliable spark for over 200,000 miles.

The negative, is there is one, is that some of the oddball characteristics of the stock points systems are also retained – such as the mechanical advance unit and the points timing plate. And with the timing plate in my hand, it was clear that this one was no longer serviceable in its current condition. BWM had, since dinosaurs ruled the earth, placed a small felt pad on a steel spring on the timing plate whose job it was to manage the delivery of an appropriate amount of ignition cam grease to the ignition cam. This one, it seems, had shuffled off its mortal coil. The spring was still there, but the business end of the felt pad was nowhere to be seen.

We Don’t Need No Steenking Ignition Cam Lubrication Felt…Oh, Wait, we do, actually.

And of course, brief research finds that no dealer or aftermarket supplier, US or European can supply either a complete points plate or the felt wiper. The Studs on Adventure Rider have, of course, found sources for just the raw felt for industrial applications, like knitting machines, and cut some to fit and riveted in place. The wrong felt though, at 6000 rpm, could do quite a bit of damage, so that wasn’t my first choice. I checked eBay, but the few available were either mad spendy — I am unemployed, remember — or in just as bad shape as the one I had.

The wipers for the older /2s are, of course, still available, so I spent a few hours trading e-mails with the estimable Craig Vechorik at Bench Mark Works – a Vintage BMW supply and restoration specialist – who pulled and measured one for me, but it was too wide to fit without further modification — in stock form it would foul the mechanical advance unit in the /5.

At the point where my anxiety was starting to creep up, fellow sufferer Al Browne took another look at eBay, and found a bike breaker in Wisconsin who had literally just listed one. It looked like it had only been on the road for 10-20,000 miles, tops, and was reasonably priced.

Thanks Al.

I jumped at it.

Three days later, the postman showed up, and I was back in the shop.

I cleaned up the new plate, greased up the felt, and reassembled the ignition system. I gapped the points — which, I gotta say, is a lot harder to see at my current state of chronological giftedness than it was as a 25 year old pup — and went to time the engine.

My first shot was nowhere close. Closing the gap from the .016 inch I had initially selected to a middle of spec .014 retarded things to closer to spec but the engine was still too far advanced. Closing down to .013 had me 2-3 degrees overadvanced but the timing plate was out of adjustment range – I couldn’t retard the timing any further. This isn’t an unknown problem – the original German-made Bosch points are NLA. The best repros are made by a German company named Noris, and their rubbing blocks are known to be a few fractions of a millimeter too large, which causes the timing to be too advanced.

After a suitable ThinkThinkThinkPooh, I pulled the plate and points back out of the bike and chucked it up in the vice on my workbench. I grabbed my cheap Dremel knock-off and the smallest diamond abrasive point, and went after the two slots in the plate which permit timing adjustment. Using this micro-grinder, I lengthened the timing slots from 4mm to roughly 5.5 mm, and then cleaned the parts off and reinstalled them. Upon restarting the bike, the timing was bang on.

(Break arm patting self on back)

I disconnected the battery negative lead, replaced the front engine cover, and torqued the cover fasteners, tightened the bronze tank retaining wingnuts, made sure the fuel lines were securely installed, and then reconnected the battery.

I trolled the bike around the block to warm it up, but the funky behavior on trailing throttle was still present, so I grabbed a 10mm box end wrench, my favorite Husky carbon steel miniature flat blade screwdriver, and prepared to perform the time-honored airhead carb synchronization ritual.

I loosened the throttle cable locknuts, and backed them off until there was freeplay at both ends. Then I started the bike and adjusted the carb butterfly stops until we had some semblance of an even idle. Then I lay down on the ground and engaged the idle air mixture screws, which I first closed, and then opened to about 1/2 turn. As I cleared 1/2 turn, the idle speed rose dramatically, so I had to back off the idle stop screw and then take another pass at the mixture screw. Clearly, for some reason I can’t fathom, the air mixture settings must have been way, way off. After 2-3 iterative passes on both Bings, I finally located the optimum air mixture setting and was able to fine tune the idle stop screws.

I gave the bike throttle from idle a few times – pickup was smooth and even. Letting go of the throttle I stood there and wondered at a perfect Putt-Putt-Putt-Putt-Putt 1000 rpm idle. I turned the bike off and locked the cable adjuster nuts down.

You have to love a motorcycle that can be tuned entirely by ear with a small flatblade screwdriver.

I went inside to grab my gear, leathered up and headed for Poffenberger Road.

 

***

 

Poffenberger Road is one of The Valley’s most notable unpaved roads, and home to several of the founding members of our ‘Friends of Rural Roads’ – http://www.ruralroadsfrederickmd.org/. Poffenberger follows Catoctin Creek for several miles and is the fastest way to get back to our slower history here in Frederick County. Ask why my /5 wears semi-knobby tires and Poffenberger Road is why. If my family must leave this place some day, this road is one of the few things I will absolutely miss.

Upon turning onto Poffenberger, it was clear that the county road crew had just been here for their spring visit — the road had a fresh layer of crushed limestone that had just been graded. The Flat Track racers that come to the Frederick Fairgrounds every Fourth of July for the Barbara Fritchie Classic would likely kill for a soft, tractable racing surface exactly like this.

This perfect dirt surface is the pass/fail test for carb sync on this big twin. Having started life as a 750cc engine, its 900cc cylinder barrels, combined with the small valves of the original 750cc heads, make for a low rpm-biased motor that is happiest in the dirt. I built this bike to be a true scrambler before ‘Scrambling’ was a thing.

Today, post screwdriver alchemy, all is right with this motorcycle and the world. Power is stong and even right off the bottom, and at 4000 rpm the engine is as smooth as its 4 cylinder cousin. I can pick my slides with the throttle, and back into corners off the gas. I run out of dirt – first on Poffenberger, then on Harley and Bennie’s Hill – long before I run out of desire to ride.

 

***

 

So now, there are three motorcycles in the garage, and three that are ready to ride anywhere. Many other things in my life might be presently out of balance, but I can take some small solace, satisfaction and fulfillment in my ability to take tools in hand and render machinery fully and properly operational (with certain previously noted exceptions).

If, in future, though, you happen to overhear me planning to take a year off from maintaining my machinery to pursue some other enthusiasm, please smack me about a bit until I recall the conservation of wrenching, and that there is inevitably a reconciliation that involves the completion of all the routine work that one incorrectly thought you had put off.

Sure, there are some small things that remain to be done. Both airheads need their gearbox oil changed but on naked or almost naked motorcycles, that operation is about a 20 minute job that involves the removal and replacement of two bolts. And after the little improvisation with elongating the adjustment slots on the /5’s timing plate, I think that making the same modification on the S’s timing plate is likely in order — that motorcycle is carrying perhaps 2 degrees of additional advance which helps under wide open throttle, but can be observed as some reduction in low-end torque and smoothness at steady rpms.

None of that is critical though — all of it can wait.

What the spirit needs most right now, though, is the quiet inside my helmet and in my soul that only a few hundred miles of a sunny day ride can provide.

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One thought on “… and Dirt Under The Fingernails

  1. I have always acknowledged that Airheads have character of the type that a wife has on her way to her lawyer. They are flawless, so it just has to be you.

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