Sorry to dredge up an old thread, but i have noticed this worrying trend, it's not just ebikes but normal human powered bikes too. I have probably had around 30 bikes since the mid-nineties and progressively the documentation provided has got worse. My first quality bikes came with Shimano data sheets for each part of the gears/brakes and even my first Hope disc brake equipped bike in 1998 came with a Hope manual. My last purchase, a Trek Xcalibur 29er MTB came with just a standard manual that seems to be aimed at all Trek's range of bike, whether road, mountain or whatever, it doesn't detail how to setup the suspension for my weight even, something quite critical for a mountain bike with an air-sprung fork. Further, i couldnt find this information even on RockShox's website.
Bicycle manufacturers need to get their act together on this, especially on ebikes as there is considerable extra complexity. That being said, the above linked Kalkhoff manual is many times more informative than my Trek manual which is completely laughable.
And in your post you've stated the root of the problem discussed in this thread.
E-bike manufacturers are just bicycle manufacturers who started tacking on motor systems at some point, Kalkhoff for example onto existing ordinary unpowered models like the Agattu and Pro Connect in 2007/8. And many of these bicycle manufacturers including Kalkhoff have made bikes for up to 100 years or more.
So they come from an era when bikes were so commonplace, standard and simple that everyone understood them, almost all could carry out the simple repairs and maintenance necessary and bike shops were everywhere. Accordingly bikes didn't need any manual, and I can say that when I joined the trade well over 60 years ago no new bikes we ever handled were supplied with them.
So it's a change of thinking that's needed. Bikes have become much more complex and variable over the decades and e-bikes have added hugely to the complexity. The industry needs to start thinking more like car and motorcycle manufacturers, supplying decent owner manuals with the products and also making available full technical manuals for those who want them as an extra. To keep costs down the latter could be as online PDF downloads.
Will it happen? I'm not holding my breath. A very few have made a good try and it has to be said that Kalkhoff are one of the better examples with considerable effort made in most areas. In their case the speed of introduction of new models and many different power units* has tripped them up at times so perhaps they need to pause and stabilise what they are doing.
*I count 7 very different power unit systems in the last 3 years in their models, and the number of model variants in that time is mind boggling.
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