Alcedo BBS01/BBS02 42T CNC custom chainring


Esteemed Pedelecer
Feb 26, 2010
Tyne and Wear
Here's a few pics of the BBS01/BBS02 42T CNC custom chainring from Alcedo e-bikes factory, which has now replaced my Bafang standard 48T chainring.
The standard chainring is a bit too large in my opinion, and the offset can be a little too far away from the BB for a decent chainline.

The Alcedo is about an extra 3mm inwards from the standard ring. I couldn't find my digital calipers, so unfortunately I couldn't get an exact measurement.

It's beautifully made and for any weight fans out there, weighs a meer 192 grams, compared to the Bafang 48T's 337 grams.


For some reason, even with the improved chainline, I still had problems with the first two lowest gears.
Maybe my frame is slightly bent or it's the cheapo cassette, but I just did what I did originally and adjusted the derailleur stop screw to omit those two gears.

With the 48v 750w it's not an issue. Maybe with the 250w version, first and second would be required for very steep hills.

What was the point of fitting this then, I hear you ask :eek:

You never know if something will work, unless you try ;)

Anyway, it has massively improved rideability when going slow, the top speed has been tamed from ludicrous to much more useable (I'm not going to divulge, so don't ask :D) and the slight chain noise I had with the original 48T and third gear has been eliminated.

I personally think it is money well spent, but at seventy quid, I would advise any potential purchasers to think whether they really need one first, before forking out.

Here's some more pics:

Bafang 48T on left, Alcedo 42T on right

Bafang 48T on left, Alcedo 42T on right
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Spotty dog

Sep 19, 2014
I use the same chainring it's not cheap but is a nice bit of kit I really didnt like the chainline issues with derailuer gears and switched to hub gears which I felt happier with.
I did try a 104 BCD adapter I got from guy on ebay came from australia contents described as beer coasters! on customs label, It's a much cheaper option to get lower gearing for off rd use but again chain line was way off like the banfang chainring will hang on to it for future projects tho something low geared for off rd use that climbs like billy goat is appealing.
(Pic of my nice chain line with Alcedo chainring)
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