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Traffic Safety, Speed, and eBikes

At what speed does a cyclist become more / less safe in traffic? Obviously, too slow can be unsafe. How fast is too fast? In this regard, would a pedal assist eBike, that can do 25 mph, be a safer solution than a normal bike?
ericf
2014-07-07 08:04:53
The faster you go the more likely you would get hit from the side or front. Cars don't see us just like motorcycles, so speed can be pretty bad at intersections and exits onto the road. It takes a longer distance for you to stop your bike to avoid the vehicle ahead that didn't see you and was not expecting a bike going 25mph. On the flip side, vehicles from the rear have a longer time behind you and are more likely to see you better. Considering most accidents happen from front and side, I would say speed isn't an advantage for safety and on top of that if you are going to wipeout on your bike due to gravel or some other issue, I would prefer to be going slower. I will point out that this is my perception and I have no statistics to back up any of it. If there is a study on this, I would be interested in the findings. I probably run around a 15mph average on my fixed and feel pretty comfortable. I would say my most dangerous parts of my ride are going down hill at a faster speed and my legs flying around the pedals, hoping something or someone doesn't pull out in front of me.
gg
2014-07-07 08:18:29
@ ericf Obviously, too slow can be unsafe. I suppose it is possible that under certain rare circumstances slower is less safe. I'm not sure that those situations exist. In any case, it is not "obvious" at all.
mick
2014-07-07 13:16:21
Well, if you were riding on a intermittently traveled curvy road with no shoulder and were able to keep up with traffic I think you'd be safer than if you couldn't. Someone coming around one of the turns would be more likely to kill you if you were going slower. But generally, I don't think there's good data about what is safer / less safe. I know that Vehicular Cyclists claim that accidents where the cyclist is hit from behind are rare; much more common are accidents where they get right hooked, doored, left hooked, etc. So that's how they justify a lot of their practices. My guess is that a lot depends on the skill and riding style of the cyclist. I don't think E-bike vs. no E-bike is going to affect the safety issue that much.
jonawebb
2014-07-07 13:39:50
I've seen an e-bike go around a 90 degree corner on a standard sidewalk going about 15 mph. While a cyclist (even me, maybe) could do that pedalling, they wouldn't. This kind of behavior will affect safety.
mick
2014-07-07 13:53:15
jonawebb stated: "My guess is that a lot depends on the skill and riding style of the cyclist. I don’t think E-bike vs. no E-bike is going to affect the safety issue that much." This is probably the most important factor. If a cyclist is going 25mph, are they watching what is ahead of them very closely and expecting the worst at all times? Do they have braking capabilities that enable them to stop well incase they run into the driver that didn't see them? Will the cyclist slow down in situations that are dangerous even though they are able to cruise at 25mph regardless of terrain? Most of the dangers out there are controllable if the cyclists expects everyone they encounter to be an idiot.
gg
2014-07-07 15:24:38
If they have the ability to go 25 mph, they'd better have good brakes.
stuinmccandless
2014-07-07 15:48:42
Thank you all for your responses. To further the discussion: @jonawebb "Well, if you were riding on a intermittently traveled curvy road with no shoulder and were able to keep up with traffic I think you’d be safer than if you couldn’t." @andyc "I would say anywhere that it’s not safe to stand is somewhere that I wouldn’t want to be at low speed on a bicycle." These are the kind of scenarios I had in mind. I have very limited experience with motorcycles on the street, but I always felt much safer on a moto than a bicycle, in traffic. (Bearing in mind that moto's have more power, better tires, better brakes, and I wore a full face helmet) On my bicycles, the faster I can go in traffic, the safer I feel. @gg made some good points about front vs. rear collisions and cycling skills that apply to all bikes (motor or not). @StuInMcCandless, I hadn't thought about brakes, definitely a concern, but modern discs are plenty good.
ericf
2014-07-08 05:44:22
An acedotal point: I ride down Troy Hill Rd in the mornings (the hill near North Catholic Highschool), and can easily reach 25-30 mph while coasting. I'm extremely cautious and I even tend to start braking before I get near Province St, just in case there's a motorist there or approaching that doesn't see me. As a rule, I always take the lane on this decent because it's one of the few cases where I actually exceed the posted speed limit. Most motorists respect that don't pull anything stupid, but every so often I get passed unsafely by someone who seems to think, "It's a bike, I should pass it!" Another reason I take the lane here is because I turn left a the Penn Brewery to cross the ped bridge over Rt 28, but that's irrelevant. I guess the reason I bring this up is: Despite going as fast (or faster) than traffic on this road, I tend to feel like I'm opening myself up to even more dangerous motorist stunts than if I was moving at a speed they are anticipating. Add in the multitasking of watching for road hazards, and things get pretty hairy. If I was going 15 mph, I might only get passed by a car going 25, instead of me going 30 and getting passed at 35-40. Anyway, just my own observations...
timecatalyst
2014-07-11 16:09:36
As a rule, I always take the lane on this descent because it’s one of the few cases where I actually exceed the posted speed limit. Most motorists respect that [and] don’t pull anything stupid, but every so often I get passed unsafely by someone who seems to think, “It’s a bike, I should pass it!”
Similarly, I have been passed --- on the right, no less --- descending Stanton Avenue into Morningside. In the particularly memorable case (an SUV, who passed me on the right on the inside of the curve across from the elementary school), my speed at the time was somewhere on the far side of 30mph, and may have been closer to 35, so they had to have been doing 40+. Between traffic lights and poor pavement at the bottom of the hill, I still almost caught back up to them by Negley Avenue. (The speed limit there, of course, is 25, though I don't think I've ever once seen a car go that slowly there, in either direction.)
epanastrophe
2014-07-11 18:39:23
I wonder how much of the impunity re speeding is due to PA's stupid restriction on local law enforcement not being able to use radar. IOW, if it was actually possible to provide cost-effective speed enforcement within the city, how much safer it would be for cyclists.
stuinmccandless
2014-07-12 12:39:03
@stu, lots of things would be safer for cyclists, and pedestrians -- e.g, enforcing the drunk driving laws, or checking to see if people had a valid driver's license, with a checkpoint. But the important thing to realize is, enforcing the laws more vigorously would also annoy a lot of people. Who vote. So there's a balancing act between what the law says and what the actual rules are.
jonawebb
2014-07-12 19:05:32
Btw if you're interested in them there's a new shop next to Frick park on Bigelow. Passed it on the All Neighborhoods.
jonawebb
2014-08-19 06:09:30
Bigelow? Do you mean Braddock?
epanastrophe
2014-08-19 12:51:29
Sorry, I meant Beechwood. Right next to Blue Slide Park.
jonawebb
2014-08-19 13:05:19