Many years ago, I was made steward of a trove of Yamaha TD1-B parts. They supplemented parts I already had—cylinder heads, carburetors, oddments—left over from running those bikes in the mid-1960s. The TD1-B was one step toward the final success of Yamaha’s 250cc production roadracer program, which came good in 1967 with the C model. That bike had the reliability to finish national races and the speed to send the competition, Harley-Davidson’s imported Aermacchi Sprint four-strokes, to the museum.

During the time that I had a dealer number from the racing department, I ordered parts I was still missing with the early prefixes of 143 and 144, as well as those shared with the production YDS-3—seals, gaskets, consumables. When I’m older, I told myself, I’ll put a complete bike together, add gas, and start it up. After that, I’ll look at it.

Recently, I found and prepared a set of sandcast crankcases and cast an eye over the several crank cores I have. I picked one and set out the parts I could reuse. My middle son, who is skilled at summoning things from the internet, presented me with a set of new ball bearings for crank and gearbox.

Yazaki motorcycle tachometer
More than 50 years after it was produced, this original Yazaki tachometer will have a new home on the author’s Yamaha TD1-B. The dial begins at 2,000 rpm.Kevin Cameron

But a tachometer could be tough. When racebikes endo, and they do, tachometers get hammered. So, with the passage of time, there are more bikes than tachs. The one I needed was on page 7 of the TD1 owner’s book: 2,000 to 14,000 rpm with the words “Yazaki Meter” at the bottom and Yamaha’s crossed tuning-forks logo at the top. No colored lines. The case in semi-matte black, with four ears by which to attach it to four individual rubber mounts. All this to protect the tach from the metal-shattering vibration of the engine.

I had the fairing mount, I had the rubber vibration isolators, and I had the tiny special castellated nuts and drilled bolts that held it all together. But no tachometer.

So when a longtime friend emailed that he had an odd tach among his considerable stock of later TZ racing parts, I paid attention. His description fitted the tach on page 7, and he said he’d put it in a box and send it. All this in the emotionless silence of email.

When the box arrived, I opened it and unrolled the foam packing. The tachometer was new, perfect, and uncirculated. There were no marks indicating it had ever been mounted. I stared at it and turned it over in my hands. Today, if I turn to the right, away from my computer screen, there is the tachometer looking at me. To make it “speak,” I must connect it to an engine via the mechanical tach drive cable, which I have. I hope to see the message soon.