Seriously (not subjectively)... Do suspension forks improve safety on Urban ebikes?

[Stefan Mikes]

Although I truly respect experience of participants in this thread, I'm rather with Ken. Off-road consists of rough terrain only and it is often travelled at high speed (downhill!); it is hard to imagine a fast single-track downhill ride without any suspension. Yet high-speed urban ride is something very different. In the city, you can ride fast provided the road is smooth. If you encounter a segment full of potholes, you just slow down. Riding into a deep pothole means the rider was not watching the road.

Thick tyres do a lot. My favourite e-bike has a rigid fork, 2" tyres, suspension handlebars and suspension seat-post. When I was riding 1.75" tyres, that "suspension" used to work hard. After replacement of the tyres to 2", both the shock handlebars and sus post work far less. The ride quality is comparable (not the same though) to my 2.6" tyre/FS e-bike, as long as it is an urban ride. Off-road is something very different.

 

[theemartymac]

I think there are certainly different opinions and experiences surrounding the definition of 'Urban'. I live in Canada (Victoria BC - 1/2 million people with the closest burbs), and several of our main bike networks are 40-50% gravel. Old rail beds to be exact, which means 30-40kph or more is certainly doable, although the various bridges, trail transitions, and street crossings can be quite variable. My 20km commute to work is 40% gravel, alternates back and forth repeatedly, and has at least 2 dozen gravel/asphalt/sidewalk transitions. I still call it urban as only about 5km of it ventures into nearby farmland right at the very end.

When I lived in the Rockies near Banff, it was easily 90/10 - gravel/asphalt riding and gravel often means exposed roots and rocks. My 'city' bikes would die a quick and painful death out there, probably just behind my back and knees. lol

 

[Johnny]

I think there are certainly different opinions and experiences surrounding the definition of 'Urban'.

Agreed, this seems to be the problem. Urban does not mean well maintained roads with a flat surface. Even a smooth looking asphalt may have quite a lot of bumps.

When I lived in the Rockies near Banff, it was easily 90/10 - gravel/asphalt riding and gravel often means exposed roots and rocks. My 'city' bikes would die a quick and painful death out there,

Exactly. And even if the bike does fine you will be bouncing quite badly if you ride at higher speeds.

As stated before on an uneven/bumpy surface a suspension fork prevents the bike to bounce excessively, hence the tires keeps in contact with the surface which leads to better control and shorter stopping distance when braking. Wide tires while increasing traction and dampening high frequency vibrations (for example vibrations while going over a wooden bridge) doesn't do enough against bouncing on bumpy/ uneven terrain. If this is not improving safety then I don't know what is.

 

[Akrotiri]

Try not to make assumptions. One of my non-suspension bike is a Gravel bike with good components , I didn't say it can not handle off road, I said they can not handle it at higher speeds(25+) there is a very significant difference between going slow and fast on uneven terrain. This is not about geometry, we are talking about the same bike fitted with a quality suspension fork vs one with a fixed fork.


That means it handles better(handling by definition covers many attributes). In terms of added weight, the 1-2 lbs added by a good quality suspension is negligible compared to rider and ebike's weight.


Completely agree.



On flats I do 20mph when the motor is turned off, I am faster on my normal road bike but honestly it is neither safe nor comfortable.



You must be lucky to live in a city with good pavement as you said that makes a big difference and "Urban environment" is not enough of an indicator of what you are going to get. Where I lived, some streets were so bad that they had giant patches that are 1-2" deep and even 50mm tires would not save you from them. I had to slow down or maneuver frequently. If the pavement is broken suspension makes a significant difference even for a bike fitted with 2.6" tires.


I’m going to have to go ahead and disagree with you again. A bike that is designed with a solid fork won’t perform as intended if you the rider recklessly swap it with a suspension fork. Bike geometry doesn’t work that way. Only some bikes from the major manufacturers have identical frames where one model has a solid fork and the other has a suspension. The allant 7 and 8 come to mind.

I wasn’t making assumptions I was responding to exactly what you said based on the info you provided.

You had trouble going off-road because the bikes geometry wasn’t designed to go off-road or you removed the solid fork and installed a suspension fork which compromised the geometry causing the bike to fail at its design intention.

 

[Ken M]

Whats that bike light mount?, I want one. I have seen several on amazon, curious which one your using.

That is actually just the rubber strap that typically goes around the bar but I put a screw threw it so it would hang under the bars in the center. It actually worked out perfectly ... cool that you noticed.

 

[Ken M]

I really did start this thread because I just kept hearing a bike with a suspension fork was safer than one with a rigid fork.

If I want the optimum comfort I would ride a full suspension ebike with a suspension seat post and a springy saddle plus a suspension fork with a suspension stem. Then toss on some fat tires and I'm riding a pillow bike.

My thought was that front suspension (while providing some comfort for your arms) really can't make the bike safer because the rear is rigid and it's just as likely to loose contact for an instant if an obstacle is encountered. I understand that city streets, sidewalks, and bike paths are not perfectly smooth but I tend to think the major obstacles are few enough that a rider paying attention can avoid them or just slow down to a safe speed.

My gut tells me that the bike industry wants everyone to believe a road/street bike is safer with a front suspension. Bean counters can do the math on the extra costs of maintaining a front fork over the life of the bike. I do know that most of the cheap bikes I see in thrift stores have forks that are simply worthless (some just had springs in a tube ... who ever thought that was a good thing for consumers must have been a bean counter).

Anyway input on the tread is interesting.

 

[Johnny]

@Ken M Imo you have asked the wrong question or you are just trying to feel good about what you believe. Your question as you have asked has been answered several times by different people and there are many resources out there. A well adjusted, quality suspension works, it improves safety and that is physics.
Moreover you wanted objective inputs but you are being very subjective about the matter yourself. Most of your statements are about your gut feeling.

Every company promotes whatever they are making. If it is a fixed fork, they make up reasons for it if a suspension front fork another reason is given. There seems to be many class 3 ebikes out there that have front fork suspension and fixed fork suspension. I don't think industry is picking one over the other.

If your question was, do lower quality suspension forks improve safety or are they necessary then it would have been a different discussion and many people already agree with you on the first, the second question is simply a matter of where you ride.

 

[Akrotiri]

I'm not an engineer so I'm gonna make an uneducated statement.

If I'm riding a bike at 28mph and hit a pothole, I think I'd rather have a suspension.

If you are unable to detect or avoid an incoming pothole on a city street at 28mph you shouldn’t be riding at 28mph on a street.

You simply lack the situational awareness to travel at that speed on an ebike on city streets.

 

[linklemming]

Although I truly respect experience of participants in this thread, I'm rather with Ken. Off-road consists of rough terrain only and it is often travelled at high speed (downhill!); it is hard to imagine a fast single-track downhill ride without any suspension. Yet high-speed urban ride is something very different. In the city, you can ride fast provided the road is smooth. If you encounter a segment full of potholes, you just slow down. Riding into a deep pothole means the rider was not watching the road.

Thick tyres do a lot. My favourite e-bike has a rigid fork, 2" tyres, suspension handlebars and suspension seat-post. When I was riding 1.75" tyres, that "suspension" used to work hard. After replacement of the tyres to 2", both the shock handlebars and sus post work far less. The ride quality is comparable (not the same though) to my 2.6" tyre/FS e-bike, as long as it is an urban ride. Off-road is something very different.

Wow, thats awesome that you have set the bar for what offroad is? Silly me, I thought it meant offroad. Cmon Man

Are you aware that people rode offroad (according to you definitions) before suspension. I did for about 5 years including many downhill courses in california(yes, that was brutal, at times you your vision was blurred) causing disorientation. Even after that I rode suspension forks with limited travel for years...many would be considered cheap by todays standards.

 

[linklemming]

I'm not an engineer so I'm gonna make an uneducated statement.

If I'm riding a bike at 28mph and hit a pothole, I think I'd rather have a suspension.

Agreed, if I was traveling at 28mph and hit a pothole I didnt see I would want suspension as well. The situation never seems to happen though.

 

[reed scott]

Haven't followed this thread but I can say, in bike riding, perhaps the greatest contributor to accidents, other than excessive speed, is tiredness. Been there done that. A good suspension reduces physical stress and enhances one's alertness and endurance. So ... in this regard at least ... suspension does improve safety in bike riding.

 

[AHicks]

You guys need to understand Ken is a commuter. That's the viewpoint he's speaking from, and from what I've seen, that's the only viewpoint he's going to acknowledge.

 

[TimJohn]

I thought e-bikes, at least in Canada, are limited to 20 mph so either everyone here are actually pushing real hard all the time above the electric motor's applied force. I have ridden my e-bike downhill to 28 mph and it does feel unsafe. I'm not sure suspension would make that feel more safe.

 

[AHicks]

I thought e-bikes, at least in Canada, are limited to 20 mph so either everyone here are actually pushing real hard all the time above the electric motor's applied force. I have ridden my e-bike downhill to 28 mph and it does feel unsafe. I'm not sure suspension would make that feel more safe.

I think a lot of us might agree on that point (myself included). Thing is, like much of what's being said here, Ken has us on a question that's very much about different strokes, and there are few right or wrong answers that apply across the board.

 

[theemartymac]

I thought e-bikes, at least in Canada, are limited to 20 mph so either everyone here are actually pushing real hard all the time above the electric motor's applied force. I have ridden my e-bike downhill to 28 mph and it does feel unsafe. I'm not sure suspension would make that feel more safe.

There is virtually no enforcement or application of ebike regulations in Canada so far. It's still early days and the tech is moving far faster than any regulation. Most bikes are sold with some speed limits, but it seems most retailers are quite free with the passwords and instructions to unlock the full potential of the bike. My owner's manual has all the info needed, including password, to unlock all the settings and limits in my bike.

And it's subjective of course, and some folks will never feel safe at speed. But that does not mean it's not safe. Mopeds, Scooters, Motorcycles, all make the transition from pedestrian speeds to highway speeds and beyond. It's simply a factor of adequate power, braking, and of course - suspension...

 

[reed scott]

There is virtually no enforcement or application of ebike regulations in Canada so far. It's still early days and the tech is moving far faster than any regulation. Most bikes are sold with some speed limits, but it seems most retailers are quite free with the passwords and instructions to unlock the full potential of the bike. My owner's manual has all the info needed, including password, to unlock all the settings and limits in my bike.

And it's subjective of course, and some folks will never feel safe at speed. But that does not mean it's not safe. Mopeds, Scooters, Motorcycles, all make the transition from pedestrian speeds to highway speeds and beyond. It's simply a factor of adequate power, braking, and of course - suspension...

For years I rode a big KTM adventure bike and had a 450 thumper dirbike. I rode with guys who followed the ATGATT philosophy. All The Gear All The Time. This saved a lot of serious injury as people were suffering all the vagaries of motorcycle riding. Especially hitting deer. Still there were hospitalizations. I was lucky. Only minor scrapes. People who want to go really fast on their ebikes should for sure wear a helmet and knee and elbow pads would be prudent.

 

[reed scott]

Tiimpo, your vast wealth of knowledge never ceases to amaze me. Who ARE you ... really?

 

[TimJohn]

The fact is most motorcycle fatal accidents occur in intersections and speeds usually not that excessive. I can understand why there is the concern for safety even at the 20 to 28 mph speeds that some e-bikes can achieve. I would venture to say that at least in my city there probably are more accidents with bicycles (not just electric) than motorcycles and if you do have an accident, its off to the local hospital.

 

[Roxlimn]

I really did start this thread because I just kept hearing a bike with a suspension fork was safer than one with a rigid fork.

If I want the optimum comfort I would ride a full suspension ebike with a suspension seat post and a springy saddle plus a suspension fork with a suspension stem. Then toss on some fat tires and I'm riding a pillow bike.

My thought was that front suspension (while providing some comfort for your arms) really can't make the bike safer because the rear is rigid and it's just as likely to loose contact for an instant if an obstacle is encountered. I understand that city streets, sidewalks, and bike paths are not perfectly smooth but I tend to think the major obstacles are few enough that a rider paying attention can avoid them or just slow down to a safe speed.

My gut tells me that the bike industry wants everyone to believe a road/street bike is safer with a front suspension. Bean counters can do the math on the extra costs of maintaining a front fork over the life of the bike. I do know that most of the cheap bikes I see in thrift stores have forks that are simply worthless (some just had springs in a tube ... who ever thought that was a good thing for consumers must have been a bean counter).

Anyway input on the tread is interesting.

You don't want to acknowledge safety studies done on suspension based on motorized motorcycles, the expert opinion of downhill racers (none of them race on rigids), and other people's experiences, but you insist that your gut rules all? I'm not sure what you want to hear or have on the thread. What people believe is their own business, but if really are looking for physics and testing, then it's really a done deal for that. I mean, yeah, you could simply never go that fast and that'll be safe on a rigid fork. Or walk your bike the entire way. Or only ever ride on smooth asphalt. All those apply. If that's you, then you don't need a suspension fork. Walk your bike everywhere. Perfectly safe. And it'll be lighter if your fork is rigid.

Cheap suspension is widely acknowledged to not be that much better than a rigid fork, and in some cases a rigid fork will actually perform better. If you were only considering cheap forks, then stick with the rigid forks. That's probably why a lot of fast ebikes have rigid forks to begin with. Cost savings and weight savings. You sacrifice comfort, but you get real trade-off benefits.

I have had an ebike with a cheap fork. I also have regular bikes with rigid forks. The suspension makes it comfier, but probably not that much safer. Once you get into the mountain-suitable forks, the suspension does begin to make a difference in terms of handling and traction. My current ebike has a 36 Fox Performance fork. No comparison. It even blows the okay suspension fork out of the water. I know I've taken spills on the rigid forks at speeds lower than what I can absolutely comfortably take on the 36 fork. That's not marketing. It's a stark difference that I feel every day on my commute. Things that I used to have to avoid as hazards are now safe. I still avoid them, but it's a load off mentally that I can take those hazards at speed and it won't throw me off.

You can just ride a rigid fork if you want. You do you. But if you're asking if it really makes a difference, then yes, it absolutely does. It's not marketing. These days, suspension companies don't even sell safety. They sell comfort and feelings of greater control. That's all over the marketing they have for these forks. Safety isn't a selling point, because all the good forks improve safety by about the same amount. And it's an accepted thing that you don't ride a rigid down a downhill track unless you're insane.

 

[Stefan Mikes]

And it's an accepted thing that you don't ride a rigid down a downhill track unless you're insane.

I liked what you wrote but you certainly will agree with me the road or a bike path is not an off-road downhill trail? What is the full-suspension lockout for?