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Cycliq Fly 6 Bicycle Rear Camera and Light - SD card recording gaps



I think the 10MB/sec claim is a sort-of max-speed-on-the-fly rating, probably on a freshly-formatted card. When the cam closes a file (for shutdown or prior to opening the next file) there is a heap of system read/writes needed to update directory entries and FAT tables for the operating system. Once you have initially filled the freshly-formatted card, issues of reclaiming used space further complicate things.

I don’t get any corrupted files when I power-off, just a picture of my palm over the lens as I hold down the button for a second or two.

My current card is a 32GB Sandisk Extreme Pro. It claims “up to 100MB/sec Read and up to 90MB/sec Write”. More relevant are the V30, U-3, and A1 ratings. Basically, you gets what you pays for.

The “high endurance” cards are old-school - class 10 with “up to 20MB/sec Read and Write” and it is fine in my car (which spat out a Sandisk Extreme after a month or so) - so wait and see.


10 MB/s is probably the initial tested sequential write speed but the sustained writes over time will be much much less, and likely even probably under 1 MB/s. The built in controller on the card is likely at the centre of the issue and it’s bus width to the memory will be at a minimum that just meets the needs. Better cards (they are more expensive as well as they need to improve bus width etc) will give better sustained speeds. Look for something that offers 30 MB/s or better ie U3 or V30, 60 or 90.

See the following for a good write up by the sdcard Association:

I also note from your camera stated specs it is either using FHD or HD recording at either 30 fps or 60 fps (and only 60 fps if at 720p) (guessing you have it at 1080p 60 fps) and I think U1 or C10 will be hard pressed at this level of requirement anyway.


The video spec is 720p HD (1280 X720) 30fps.
Recommended MicroSD card: Class 10. The Sandisk 32GB card I’m having issues with is Class 10.


That’s if a good quality controller is on the card. The Class 10 is I think bare minimum spec for what you are doing and would need to be a better quality C10 (noting C10 is not UHS1) and C10 probably if a new card would achieve the outcome but as it is used I really think your sequential write speeds would plummet and perhaps part of the reason you are seeing the outcomes atm… When they co label a card eg C10 and U1 don’t expect the same write speeds ie from the “Note that expected write speed will not be available by a combination of different class symbols such as Class 10, U1 and V10 even those are indicated to the same 10MB/sec write speed”. Many of the cards I use for basic camera work are indeed co labelled ones and if I want hi speed continuous shots I have to put in a much better card.

According to the tech specs they publish your device only does 60 fps at 720p (

“Bike camera resolution: 1080p Full HD video at 60 fps or 30fps (1920×1080 16:9), 720p video at 60fps (1280×720 16:9)”

I understand you are getting what you are getting but does your device have the latest firmware? The firmware page does indicate that it had issues with some SD card performance and updating may be the answer?? “Improved video quality – there were reports of occasional dropped frames and this has now been remedied.”, “Improved SD card detection and formatting process.” & from the previous firmware update “Changed the Fly6 CE’s reaction to an incorrectly formatted microSD card. Now, after fix, if card is in inappropriate format, the “error” warning flashes, with all bezel LED’s together, and “no SD” audible warning sounds…//…Fixed recording so that there cannot be recordings of 0 seconds – all files must be at least 2 seconds long” I have included a link that gets you to that page:


That’s a different model to mine, but I did install the latest firmware before I started using it.
Mine is definitely 30fps at 1280X720 pixels.

(it is much clearer if you click on the image)

I’m planning to see if I can find a faster card next time I’m in town.


Np :slight_smile: (extra for the 20 characters)

The bitrate for the Avi file is from my calculations roughly 81 MB/s using the total bitrate of 663552 kbps (includes a 512 kbps audio rate) from your image. But this is of course Avi but still the amount the card would have to write per second is probably well over the 10 MB/s (81920 kbps) if it saves in Avi format and also my calculations do not take that into consideration that this may be a conversion to Avi from another format with a lower bitrate which the device actually uses.