M Part MegaHorn

The M Part MegaHorn makes a loud trilling noise to alert other road and path users of your presence; it gets people's attention but I'm not sure it's better than the classic, friendly cha-ching of a bike bell when it comes to the balance between 'alert' and 'alarmed'.

The MegaHorn is dead easy to use. Press the button (it has a remote) and a din like a dalek singing in the shower ensues, causing folks to look round wondering what the hell that noise is. On the one hand, that's good: people know you're there. On the other, it's not a sound you'd associate with a bike and rider so it confuses some people.

You could make the case that a standard bike bell is sometimes too polite, but at least when people hear it they're expecting a bike. The MegaHorn's electronic warble is borderline obnoxious and is not going to endear you to the kind of person who thinks a bell is a signal of entitlement.

Still, if you ride on the kind of crowded city streets where pedestrians tend to just step out, it does the job (though I think in those situations it's better to ride well away from the kerb so you've room to take evasive action; it's your responsibility not to ride into people, both ethically and according to the recent changes to the Highway Code).

Reliability & water resistance

Some users report that their MegaHorns just stopped working after a short while. I've had no problems.

Thinking that water might have been the cause for those people, I doused the MegaHorn with a water spray to simulate a rain shower and it still worked, so it seems to live up to the claim of being water resistant. M Part doesn't specify an ingress protection rating (that's the code like 'IPX6' you see on many water-resistant electronic devices), so we don't know just how water resistant it's supposed to be.

I then left it under 10cm of water for 10 minutes and after that it still worked, so I'm content to say that it's as water resistant as it's reasonable to expect, and maybe more so given there's no sealing round the battery case and there are gert holes up front to let the noise out.

It runs off a 9V battery but you have to supply your own, which seems a bit stingy.

User reviews of the MegaHorn reveal an extra use case that hadn't occurred to me: getting a motorbike without a horn through its MOT. Apparently some enduro and motocross bikes don't have horns; strapping on a MegaHorn fulfils the legal requirement at MOT time.

Value and conclusion

Price-wise, it's in the ballpark for decent-quality noisemakers. It's a bit cheaper than the £29.99 Hornit dB140 (full review of that to come), so decent value, if more expensive than most of the electronic noisemakers you can find on eBay and Amazon. There's a mini version of the MegaHorn too, for around a tenner less, with a 70dB output rather than the Mega's 105dB.

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The MegaHorn certainly succeeds in its mission to provide an 'audible presence', I'm just not convinced it's the right sort of presence. If you really want to make pedestrians jump out of their skins, you might as well strap an air horn to your bike. A schoolmate blew one at me from his bike when I was a teenager; I've never got across a road quicker. You can even get hand-pumped horns that don't need batteries or gas canisters. They probably won't get your old KTM through its MOT, though.

Who should buy the M Part MegaHorn? Anyone who rides busy city streets, wants to alert inattentive road users of their presence and finds a standard bike bell just isn't loud and piercing enough. Just be prepared for a bit of confusion and possible narkiness.

Verdict

Does the job, but compared with the friendly ching of a bell, it's a bit unpleasant