How effective are reflective sidewalls on bike tires in making a bike more visible during low light conditions?

Well, they show up pretty well on my bike.

They're plenty visible. As far as *effective*... well, I've been hit w/o them but not w/ them. So there you go.

Pretty good, far more effective than a stock wheel reflector.

However, I coloured in mine with a marker pen. I think they look too silver in the daylight, makes your nice black rims and disc brake setup look like you've reverted to rim brakes.

If someone broadsides you it is unlikely the reason is they did not see you. I am not against them but they probably do not get you much extra safety.

Big round and white, they show up well

I doubt they do much. If you're already in the headlights of a car that's pulling out of a side street, it's probably too late to prevent anything. You should have good lights so that you're noticed in advance. And those things get covered in dirt anyway and are a pain to keep clean. However, I see no harm in having them and theoretically they may do some good. So you can get them, of course, but don't rely on them to make you visible. Active lighting is a lot more important for cross-traffic visibility.

They can't hurt!

Not very.

I recently took pictures of one of my bikes with brand new reflective tires - with and without the flash.

The pictures with the flash were definitely more noticable, but not the type of difference that's going to keep you from getting hit by a car. Given a choice between black and reflective I'd still buy the reflective.

X2

I still want these in the Rattleback pattern.
https://www.sweetskinz.com/

I have a marathon slick on my toronto commuter and a snow stud on my calgary winter bike - as far as I can tell the grime/guck/salt has completely obscured the reflective sidewalls - the reflective coating seems to be worn out in spots too. I'll try setting up a viewing sometime to see if any of it is visible, but given the dirt, I doubt it.

The reflectors on the wheels are visible AFAIK.

Actually, I have a picture of my bike which I accidently took with a flash which made the tire light up, then I decided to take a close up picture of it!

They definately light up and are visible at night time and will be noticed. Maybe there are different brands with different reflective 'qualities' out there ... mine clearly show up, not just in the picture, also out on the streets. Like Chephy was saying, if you bike along a sidestreet or even worse, an alley, it might be to late; I certainly agree, but this scenario could happen in daylight as well. I find that they light up from wide angles and therefore makes you visible approaching and coming through intersections from a driver's perception.

If you commute in the dark a lot, I'd say give them a try, neither you nor traffic around you will be dissapointed.

The reflective sidewalls on my old Marathons were okay, but unless you keep them clean (guess it depends on where you ride), they can get muddied up extremely quickly.

Invariably most of my incidents wouldn't have been rescued by these though, I just need a few hundred lights at the front to make it clear that I'm on the road. 6' tall, around 200lbs, lights on the bike, I don't ride right at the side of the road, and I still get idiots in vans that seem to be incapable of seeing me.

I have reflective sidewalls on several bikes and I have seen them while driving. If someone is paying attention they are visible from a pretty steep side angle and are obviously a bicycle. I also like the small pieces of reflective tape on the rim. They give you a strobe effect.

Aaron

have a pair on my commute bike. I think they work great. Bike friends who have seen me tooling about at nite have told me such.

Problem around here is that all the road grime covers the sidewall, obscuring them.

They're no Force Shield....

Though, if you're driving in the dark frequently, it won't hurt you! The dirt part ... I haven't cleaned my tires in literally years driving on paved and compacted (white stuff ... language barrier here) roads. If they do get dirty quickly, I'd clean them by means of a quick wipe.
To come back to the core question of reflective tires being effective. Argueable always, but I'd say yes. They do light up in poor lit conditions and are noticeable to other traffic.

I definitely notice the other commuters who have them, even just showing up in the beam from my bike light.

+1

So, what do you think lambo?

Amsterdan,
I guess I'll go with a tire with reflective sidewalls. They can't hurt and could possibly help visibility.
I was having to decide between the Vittoria Randonneur at Nashbar without reflective sidewalls and Marathons from Airbomb that have them. I know that Vittoria makes Randos with a reflective sidewall but
they're quite a bit more than those from Nashbar.

They can't hurt; my problem is that you can't get any tire you want with the reflective strip. Maybe they should make a law requiring ALL tires to have that feature? Yikes, more regulation, but there are plenty of dopes out there riding without any lights or reflectors so maybe it might help.

Take a look at mine, after a half a year and a lot of dirt they still light up with a flash. As to effective, well, I'm not sure how often cars will loight them up in time to do any good. Wear an ANSI Class 2 safety vest. It will be far more effective than sidewalls.

I wonder what percentage of bicycle accidents involve being T-boned? A large reflector or light on the back would probably be the best investment. Any increase in visibility or conspicuity can't hurt though.