You've fitted a dashcam to your bike — but is it really capturing clear footage?
Then, checking the footage on my computer for the first time in a while, I found the picture had turned strangely hazy and white…
It's been about a month since I fitted the Daytona Mio MiVue M820WD — a proper front-and-rear twin-camera dashcam — to my Honda X-ADV.
*My previous instalment covering the installation is here:
That earlier post focused mainly on close-up shots of the cameras themselves, and a few of you told me it was hard to picture how everything sits on the bike as a whole. So this time I'm sharing full mounting shots front and rear, plus the rear camera's cable routing in more detail.
On top of that, comparing footage from just after installation with footage from a month later, I noticed something odd: a cloudy, white haze had appeared — but only on the front camera.
In this post I'll explain why a lens can cloud over even without riding in the rain, how I cleaned it using Plexus (and the important rule in the manufacturer's manual that I nearly overlooked), and I'll review the high-endurance microSD card I've been running trouble-free for over a year.
【Dashcam reviewed in this post】
Daytona Mio MiVue M820WD (front-and-rear GPS dashcam)
Built around a Sony STARVIS sensor, with excellent image quality, strong low-light performance and a compact, waterproof design.
1. Recap: the M820WD's full mounting layout and rear camera cable routing
Here's a proper look at where the cameras sit on the X-ADV as a whole, plus the cable routing I put some real thought into, none of which made it into the previous post.
Front camera mounting, full view
The front camera is mounted using a bracket shared with the mirror base, so it's fitted without any modification to the cowl.
It sits neatly above the headlight, tucked in behind the cowl, and looks tidy even when you view it head-on.
From the riding position, it doesn't block your view of the dash or the screen at all, so your natural riding posture isn't affected.
Rear camera mounting and cable routing
The rear camera uses a PLOT number plate bracket and is fixed to the upper right of the number plate.
Exposed cabling at the back end looks scruffy, so I've routed the cable from behind the mudguard through into the tail cowl.
To avoid pinching and eventually damaging the cable, I cut a small notch at the join in the cowl and routed it through there — picking a path that keeps it away from direct water and mud where possible.
2. Comparing the footage: a strange white haze on the front camera only
I pulled the microSD card taken just after fitting the camera (early August) and compared it with one taken after about a month of riding (early September), checking both sets of footage on my computer.
Straight after fitting: a clear view
The footage from right after fitting showed high contrast thanks to the STARVIS sensor — even the texture of the tarmac and number plates on the car ahead came through sharp and clear.
A month later: something odd, front camera only
A month on, I played back the front footage and was genuinely surprised.
The centre of the frame outwards was cloudy and hazy, as if a thick fog or mist had settled over the lens.
My first thought was condensation inside the camera, or some kind of fault. But the rear camera's footage from the same month wasn't clouded at all — it was still perfectly clear.
3. Why only the front camera? How a lens gets dirty even without riding in the rain
When I went to check the bike, the cause was obvious straight away: the surface of the front camera lens was coated in a white film.
But I haven't ridden in the rain — so why?
Over this past month, I haven't ridden in the rain even once.
So how did such stubborn grime build up?
The answer turned out to be a combination of condensation inside mountain tunnels and road spray thrown up by vehicles ahead.
- Wet tarmac inside tunnels: in mountainous areas, tunnels often see heavy condensation on the walls and road surface — even in summer — due to the temperature difference with the outside air, so the surface is often damp.
- Fine spray thrown up by vehicles ahead: lorries and other vehicles running on wet tarmac throw up a fine mist containing road-surface oils and silica (mineral particles).
- Rapid drying in the airflow: sitting right at the front of the bike, the front camera takes this muddy spray head-on. The airflow then dries the moisture almost instantly, baking a thin film of grime onto the lens.
The rear camera, on the other hand, sits above the number plate and in the shadow of the mudguard, so it never takes that spray from the front — which is exactly why it stayed clean.
4. Cleaning the lens: using Plexus, and the important rule in the manual
To shift the grime, I used Plexus, the go-to plastic cleaner I already had in the garage.
I sprayed a small amount of Plexus onto a microfibre cloth and wiped the lens surface gently, without applying any pressure.
After wiping it down, the lens looked as clear as new, and when I checked the footage on my computer, the white haze had disappeared completely.
A note of caution: the correct cleaning method per the manufacturer's manual
Here's an important point worth flagging.
I reached for Plexus purely for convenience, but the official manual from the manufacturer (Daytona / Mio) does flag some cautions around using chemicals on the camera.
※Important notes on caring for the camera
- Routine care: wipe gently with a soft, dry cloth (such as a lens cloth).
- For stubborn dirt: use a well-wrung cloth dampened with water, or a diluted neutral detergent.
- Do not use: thinners, alcohol, benzine or abrasive cleaners — these can damage the lens coating and plastic parts, so they must never be used.
Coating products like Plexus can give a temporary water-repellent, anti-fouling effect. However, depending on how it interacts with the lens's anti-reflective coating, there's a risk of damaging that coating layer — using it is entirely at your own judgement and risk. For routine maintenance, I'd recommend wiping with a damp cloth and a soft lens cloth as your first port of call.
5. Choosing the right microSD card for a dashcam — my pick after a year of use
Nine times out of ten, when a dashcam fails to record footage you actually needed, the cause traces back to a badly chosen microSD card — either it's worn out or it simply isn't a good match for the device.
Checking the footage: the process
I remove the waterproof cap on the M820WD unit and take out the microSD card.
Don't use a standard SD card — a dashcam needs a "High Endurance" one
A dashcam continuously records high-resolution footage front and rear, overwriting old clips in a loop the whole time the engine's running. Use a cheap, everyday card meant for storing phone photos and you'll hit its write limit in no time, leading to freezes and errors.
What I use: SanDisk High Endurance 256GB
This is the card I've had running in the M820WD, and I haven't hit a single error in over a year of use.
- Model: SanDisk High Endurance
- Capacity: 256GB
- Spec: microSDXC / V30 / U3 / Class 10
It uses high-endurance NAND flash memory purpose-built for dashcams and CCTV, designed to cope with intense rewrite cycles and hot summer conditions. With 256GB on hand, it holds a full day of high-quality footage on a long tour without getting overwritten.
Once I've backed up the footage on my computer, I put the card back into the unit and tighten the waterproof cap down firmly to finish the job.
6. In summary: regular lens checks and a high-endurance SD card for a dashcam you can rely on
The Daytona M820WD is a genuinely good dashcam, recording beautifully both day and night — but it had a blind spot I hadn't expected: the front camera picks up grime from vehicles ahead without you even noticing.
- Even without riding in the rain, condensation inside tunnels and similar conditions can dirty the lens
- Check the front camera lens regularly and give it a wipe with a damp, soft cloth
- To avoid recording errors, always choose a high-endurance microSD card, such as the SanDisk High Endurance
If you ever needed that footage after an incident, only to find the picture too hazy to read a number plate, or the SD card had failed and recorded nothing at all, the dashcam would have been pointless.
So next time you're washing the bike or doing the chain before or after a ride, it's well worth adding "give the camera lens a wipe" to your routine.
Disclaimer
*The cleaning methods and chemicals covered in this post reflect my own personal experience. If you choose to use a chemical such as Plexus, please consider the potential effect on your lens coating and proceed entirely at your own risk. For routine maintenance, please follow your manufacturer's instructions (damp cloth and neutral detergent).
A note for readers outside Japan: the pricing and some retailer links referenced in this post (Amazon Japan, Yahoo! Shopping Japan) reflect the Japanese market. The number-plate mounting bracket is also designed around Japanese plate dimensions, so check compatibility with your own plate size before ordering. The Daytona M820WD, SanDisk High Endurance card and Plexus cleaner themselves are all available through international retailers.