An intriguing backdrop to this photo of a Triumph Model H. There is a note on the reverse of the photo saying, "Wilhemstrasse 2. 1921". Note the unusual belt driven speedo drive on the front wheel, something I personally have not seen before.
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| Sehr gut! Triumph Model H |
I've never seen that either, but I see by the Internet that the Austin 7 car (and I assume others) used a belt drive from the propeller shaft to operate the speedometer drive. It would be a relatively inexpensive way of using the same speedometer design for different uses, by varying the size of the pulleys. Best of all, the belt drive would be one more darn thing to keep adjusted, lubricated and clean. Fun! At some (probably early) point, you'd give up and remove the speedometer. Thus fewer photos of this arrangement in use?
ReplyDeleteHi David,
ReplyDeletePretty much all early bike speedos were optional devices and used a gear bolted on to the spokes of (usually) the front wheel so they too were easily calibrated for different wheel sizes.
I didn't know that Austin Sevens used a belt brive for the speedos. That makes the drive on this Triumph seem a little less quirky.
Down the rabbit hole of early speedos! If you are not familiar take a look at the Bonniksen Isochronous. Very fine and very desirable but mind boggling in function!