Knog Blinder Arc 5.5

So I was lucky enough to get the (newish) Knog Blinder Arc 5.5 front light from NickJ some months ago, and I’ve been meaning to review it, but I got lazy. Sorry Nick!

The Knog description and features of the light can be found here.

First things first, I’m not Blakey when it comes to lumens and beam angle and beam width and so forth. I just like to be visible, and if I am riding in the hills near my house, to see where I’m going (as well as being visible), and the Knog light does both.

The Blinder comes with two bar attachments, (both silicone like all Knog products), one attachment for 25-30mm bars, the other 30-35mm bars. It also comes with a helmet mount. The three bikes I used it on had bars that were either 26.0mm or 25.4mm bars, so I used the smaller sized attachment. The attachments are swapped using a small allen key (also included). One issue I had was that there is a little metal hook-clip that needed to be swapped between the rubber attachments of the two sizes. I had to swap this over and I felt like I was going to tear the rubber trying to get it off one attachment, then tear it to get it onto the other one. This isn’t a huge issue, but if you’re swapping between bikes with different sized bars, it could be a problem. Pretty much all of the Knog lights I have used over the years have had the rubber casing torn so they’re not useable anymore. If Knog offer replacement attachments for sale it will be great. There are also rubber shims to attach to bars smaller than 25mm.

Out of the packet the first thing I noticed was the weight. Apparently it’s 150g, but I had been using a Knog Boomer front light for the last few years and this felt heavy (3 times the weight of the Boomer) but a lot more solid. Once on my bars, the weight wasn’t noticeable, but the size and weight can be a bit frustrating when off the bike when I’m at the pub, etc.

The light I received was completely flat. I assumed it would be like my other Knog lights and couple hours in a computer or wall charger it would be good to go. I ended up charging it overnight in an iPhone USB wall charger before the red indicator light changed to green to tell me it was fully charged. I’m not a huge fan of leaving things charging plugged into walls overnight (or into computers), so this was a bit worrying. I can charge it at work, so that’s okay, but I’m not always at work. The other problem is that it has a small flip out USB plug at the back of the light. I found that unless you have the light plugged into a laptop on a flat surface, it just dangles there. It came with a (short) USB extension cord, but remembering to have that on me is another thing. Same with wall chargers. I have to find things to rest the light on while it’s charging. I have only charged it three times since owning it though (~2 months)

On my bars it was fine. I mounted it with no issues, and on my CX where the cables usually get in the way, it went on no issue. I have a Blinder rear light and the “clamping” mechanism is the same. Pretty straight forward and doesn’t seem like it will tear as easy as other Knog lights where it hooks shut. The two other bikes I mounted it on were flat bars / town bars so cables weren’t an issue. One thing I have noticed is it seems like the light slowly slips upwards on the bars as I go over bumps. This is frustrating and it happens on all three bars, even on the 26.0mm clamp. I find myself slowly pushing the light back down. I’m assuming the included shims would help, but I haven’t tried as I use this light on different bikes. I played around with helmet mount but it seems like it’d be a pain in the arse to take the light off the mount regularly.

The light comes with four modes, one is flashing, and three steady modes (bright, brighter, brightest for lack of better words). I use it mainly on flashing and occasionally steady.

As for the actual brightness of the light, as I said I was using a Knog Boomer front light (and my wife still does). These are fine for being seeing (just), but not much else, particularly night or early morning hill rides. Knog claims the light can be seen for 1000m and I believe it. I use it on the flashing mode for commuting to and from work in Adelaide CBD. Even in daylight it is bright. When I have used it as steady light it lights up the whole road. I commute on suburban backstreets where cars don’t like giving way or even pretending you’re there and having a decent steady bright light at night makes a huge difference. The flashing light in the mornings and dusk is great as well. I compared it to my wife’s Boomer and that wasn’t even visible with the Blinder on the lowest steady setting. I haven’t had a chance to take it out on a night hills ride, but I reckon it’d be up to task. I’m not sure about technical single-track or so forth, but when you’re on a road it’d be fine. You might not get any KOM / QOM’s descending though. I also found that from the bars you can’t see the any light coming from the top of the light, it is all directed forward. With my Boomer, climbing was so frustrating because the light coming from the top of it would shine into your eyes as well as the road.

I’ve ridden in quite heavy rain with no problems either. Knog claims it’s 100% and it seems to be.

So that’s it. As I said, I really need to take it up into the hills to and test it against a Blakey approved dynamo to see how it fair there, but as a day to day light I have no issues.


Eff off bright[/ul]
[ul]Multiple clamp sizes for different size bars[/ul]
[ul]Easy to attach to bars[/ul]
[ul]Long time between charges (a few weeks if it’s mainly used on flashing mode)

[ul]Swapping between clamp sizes can be fiddly and possibly tear the rubber attaching the metal hook[/ul]
[ul]Seems to slip and start pointing upwards on my bars after only a few k’s of normal road riding[/ul]
[ul]Long charge time (7 hours according to Knog)[/ul]
[ul]The USB plug makes it so the light needs to be resting on something if it’s in a wall charger[/ul]

If I didn’t get this for free, I would still buy one (in fact I was looking at upgrading my front light anyway) and after using it, my wife is looking at upgrading her front light to one of the Knog Hi Power Blinder range.

It went flat (or so I thought) as I was riding home late last night. I had fully charged it earlier in the week (Monday or Tuesday). Left it on charge all night in an iPhone charger (9+ hours) and it was showing fully charged this morning. Went to turn it on and it was flat. I’m going to try and charge for a few more hours today and see if that makes a difference. If not, I’ll be buying another light at lunchtime.

EDIT: Have tried charging the light using various computer USB slots and a different iPhone charger for two hours. No difference, except the light is showing “green” (fully charged). When light is turned on, it flickers and dies.

I’m assuming the light wasn’t brand new when I received it, but I’ve been using it pretty much 5-6 days a week, 98% on flashing mode and it has only lasted ~3 months.