When Mark Delaney called me a few days later, there was almost no good news.
“Well, Greg, I know your bike is badged and titled as a 1975, but you have one of the infamous not-quite-ready-for-prime-time 1974 gearboxes.”
While I spoke to Mark on the phone, I walked out to the garage to look at my build plate on the headstock of the bike. The build date on the plate was November of 1974, a few short months after the model year changeover. As frequently happens with BMWs, anyway, it was reasonable to assume that the changeover to the later style gearboxes, which had updates to the shift forks and the dimensions of the gearsets prompted by widespread failures of the original design of BMW’s first roadgoing 5 speed, hadn’t exactly coincided with the beginning of the new model year. The Works had 74-spec boxes left over, so they used them until they ran out.
“Your input shaft is probably serviceable, but if you mean to keep this bike for a while, it’s objectively toast. The 74 internals are basically junk, anyway, so it hardly matters. What’s weird is that the bike does have the later sport upgrade shift cam kit, which makes no sense at all.”
Paging Mr. Messerle to the courtesy phone. Mr. Messerle, courtesy phone, please.
“Your best bet, given how much BMW gets for these parts – the input shaft is $475 alone – is to look for a good condition parts gearbox. It’s a bit of a crap shoot, but if we get a good one, it’ll be fine.”
We both agreed to take to the Intertubes, and see what might be found on the parts breaker sites and on E-Bay.
A couple of days later, my new smartphone – to which I was a very late adopter – lit up. It was an e-mail from Mark. There was an E-bay link, so I clicked it.
The seller was an outfit called WerkstattSF – a San Francisco-based independent BMW shop, owned and operated by a female master motorcycle mechanic. The shop has an excellent reputation, and it is my attention to add to that reputation here.
I looked up the shop page on the web, and called them during my lunchbreak from work. I asked to speak to someone who had firsthand knowledge of the E-bay listing. The gentleman that answered phone told me that he had been the mechanic that had broken the bike down, and would be happy to answer any questions I might have.
Again, the Shamieh luck seemed to be running on a full charge.
The gearbox, he told me, had been pulled from a 1979 R65 with just under 50,000 miles. The bike had been taken in trade from a customer, and had been running and in use when it was traded. The gentleman on the phone had ridden the bike before agreeing to the deal. The bike had run well, and had shifted well.
“But of course,” he said, “R65s aren’t worth anything, so we hadn’t been able to sell it.”
So they’d decided to part out the bike.
The input shaft was in decent shape, all the seals had been sealing, the case wasn’t corroded, and the gear oil had been clean, devoid of excess moisture and metal bits when drained. And if I bought the gearbox, he’d personally make sure it got into the UPS that afternoon.
Let’s think about this for a second. If one wants to buy used BMW powertrain parts, one wants them from the lowest powered bike in the line – the 650cc R65 was the smallest, lowest horsepower bike BMW sold in the US. Low power means not enough power to stress and damage shafts and gear faces designed to transmit power out of a 1000 cc boxer. The mileage was low, and the shop selling the parts had maintained the bike the parts were being pulled from.
In every way, if this was a bet, these were the best odds you were going to get – a best case scenario.
Imagine an imaginary ‘Shamieh Luck Odometer’ with the numbers spinning up faster than the human eye can discern.
I thanked the kind gentleman, more or less sprinted back to my desk in the office, and bought the gearbox. I had it drop-shipped to Mark’s place.
So I was forced to more or less twiddle while UPS got my metal from San Francisco to Maryland, and while Mark cleared enough space in his life to focus on my project on his workbench.
If there’s one thing I’m really not great at its patience while one of my motorcycles is scattered all over the workbench. BMW used to use ‘Worth the Obsession’ as one of its advertising slogans, and I’m here to tell you that the peculiar form of Obsessive Compulsive Disorder that I suffer from while one of my bikes is broken – twitchy, unable to focus, eyes pointing in divergent directions and drifting further apart, nervous and jerky – is absolutely, completely, totally not worth it. It may not be in the American Psychiatric Association’s handbook of recognized mental illnesses, but mental illness it definitely is.
And if you don’t buy that idea, just ask Doris.
After what subjectively seemed to be centuries, Mark called me to tell me that he had completed my gearbox. He related that the parts gearbox had been everything he had hoped it would be, and all the components he needed – the all three shafts and the associated gear clusters – had been in remarkable shape. He had combined the parts box shafts and clusters with new bearings and seals and my shift cam kit and case to produce something with which he was completely happy.
I told him I’d be over immediately if not sooner.
And so I found my increasingly aged-seeming and achy butt (and the rest of me, too) back out lying down on the concrete slab in the garage with tools in hand and a gearbox to reinstall.
In the scheme of things, it really isn’t that bad a job, with the possible exception of the effort and technique needed to line the swingarm bushings back up to reinstall the pivot pins and the fiddly nature of getting the driveshaft bolts and the associated boot back in place given the inch and five eighths of room that’s available for both of my chubby hands. The installations of swingarm pivots are actually trivial once one figures out that reinstalling the drum brake rod and activating the rear brake actually pulls the entire assembly almost magically into alignment.
If you’ve been struggling with this, you’re most welcome.
If your bike has a disk braked rear, then you’re on your own, and I can’t help you, son.
I’ve had a lot of fun at the expense of the man I’ve been jokingly referring to as Ham Pugnus – the ham fisted mechanic.
There are lots of areas of human endeavor where professions are thrust into close contact with people who exemplify the polar opposite of that for which they stand. You no doubt know what I’m talking about – the old saws, which I neither affirm nor deny – where cops spend so much time with criminals that they start to become them, where lawyers become sophisticated swindlers, where accountants become embezzlers.
I guess that I spent so much time contemplating the manifold mechanical misdeeds of Ham Pugnus, that I became him.
During the reinstallation of the gearbox, there is a simple step where the input shaft of the gearbox needs to be lubricated – in an exceedingly frugal and minimal manner – so that the clutch release mechanism will operate smoothly when the clutch is disengaged and reengaged during each gear shift. Skilled BMW mechanics use a tiny acid brush to as to tightly control the amount of high pressure grease that is applied.
If one consults reference books on how to perform this task, they tell you two things – never overlubricate the coupling, and absolutely never ever lubricate the female part of the coupling. Either of these two fundamental errors will all but guarantee that the clutch friction material will become contaminated, rendering it all but useless for its intended purpose.
The last time I’d done a BMW motorcycle clutch job was about 20 years previously. I’ll admit to being a bit tired at that point in the procedure.
Anybody want to take bets on what I did?
The rest of the bike went back together fairly quickly. I worked as carefully as a wanna-be Ham Fist can work — checking a few things twice, like the clutch and carb cable adjustments. During final assembly, I made a few final tweaks, like swapping the original matte black grab rail and sport rack back in place of the Brown’s backrest unit. Restoring the bike to its original lines was exceedingly pleasing to the eye, and made me wonder what I’d been thinking living with it the way it was.
Having completed reassembly, I rolled the S out into the driveway and fired it up.
I rolled through my suburban neighborhood, short-shifting the first three gears. With the understanding that BMW gearboxes generally were not designed with short shifting in mind, my first impression was that this gearbox was more precise than any other BMW gearbox I had ever experienced.
Those of you that know BMW’s motorcycles will no doubt vouch for the fact that their transmissions, while strong, have never exactly been paragons of refinement. This one, though, especially when one considers its provenance as a collection of components from at least three former gearboxes – that we know about – was really a testament to the skill and care of its builder. When operated with the proper deliberation that all BMW transmissions demand, this transmission went between gears with precision – positive shifts, with no banging or clashing of bits whatsoever, which was a pretty radical departure from at least the half dozen or so BMW boxes with which I could claim familiarity.
It was late on a Sunday night, so further evaluation of my work in progress would have to wait until daylight Monday.
To continue reading, Part Ten of the story can be found here…