Does suspension make street riding safer???

[Ken M]

I've read claims that having front or full suspension on a fast urban mobility ebike actually improves safety. I understand that it does improve comfort (although there is a lot of evidence that larger air volume tires in 2" / 50mm widths or wider can provide 70% or more of the vibration and shock dampening of active suspension) but does active supension really make a street ebike safer?

Note: I understand that a worse case direct hit of big pot hole or curb at high speed a suspension may be the difference between a crash or not but I really don't want these extreme cases be the basis of this question.

Both front and rear suspension adds to the initial cost of a bike and increases service and maintenance but I think the industry wants even street riders to believe they need front forks at minimum. I think it's mainly a marketing gimmick but maybe there is a real safety component to the decision.

 

[Bicyclista]

To the extent that suspension helps keep your wheels in contact with the ground, that is definitely a safety factor. After all, you cannot control your bike with your wheels in the air.

And to the extent that comfort reduces fatigue, that would also be a safety factor. Many accidents are caused by fatigue.

For decades I rode conventional street bikes without any suspension, and I did not feel I needed any. My conventional mountain bikes had only front suspension. I felt rear suspension robbed pedaling efficiency. But the higher speeds and longer trip distances of ebikes have changed my thinking. I now believe all ebikes should have at least front suspension and a good seatpost suspension even with the plus-sized 3-inch tires I use on my Haibike. Pedaling efficiency losses are moot on an ebike.

 

[rich c]

The caveat is that all suspensions aren't the same. A spring fork is a horrible solution. Sure it moves, but nearly impossible to adjust to the rider weight or riding conditions. Nothing safer about cheap spring forks.

 

[Bicyclista]

I agree. The assumption is that you get a good suspension, not a bad one. You should get a good electric bike period.

 

[Ken M]

To the extent that suspension helps keep your wheels in contact with the ground, that is definitely a safety factor. After all, you cannot control your bike with your wheels in the air.

And to the extent that comfort reduces fatigue, that would also be a safety factor. Many accidents are caused by fatigue.

For decades I rode conventional street bikes without any suspension, and I did not feel I needed any. My conventional mountain bikes had only front suspension. I felt rear suspension robbed pedaling efficiency. But the higher speeds and longer trip distances of ebikes have changed my thinking. I now believe all ebikes should have at least front suspension and a good seatpost suspension even with the plus-sized 3-inch tires I use on my Haibike. Pedaling efficiency losses are moot on an ebike.

A suspension seatpost is not going to help keep your wheels in contact with the ground (I do truly understand that the merits of a suspension when mtn biking is more about keeping traction than comfort) so seems you kind of flip-flopped a bit on your justification.

Also seems to me that ebikes allow most riders to sit a bit more upright on a bike which dramatically reduces how much pressure there is on arms and hands which must reduce the merits of a front fork (I remember when I use to ride a rigid mtn bike on challenging downhills back in '80s (aging myself) how tires my arms and hands would be after the ride (it was because when going downhill a much greater amount of your weight is on your arms but that rarely happens when street riding unless you really love to be in an aerodynamic position. As you pointed out, does being most efficient matter on an ebike.

I think I started thinking about this after looking at the service expectations on suspension components. I think most air forks are supposed to be serviced (like rebuilt) every 200 hours of riding and that can cost $200 at a shop. That's a big cost factor if you use your bike for real world transportation. I think the bean counters at most ebike companies still want those extra profits regardless of actual merit.

 

[sc00ter]

My ebike does not have any suspension except a seat post. I also have narrow(ish) tires that I run at 60psi. This is a Pedego City Commuter. Its tops at around 20mph and on a bumpy road or sidewalk its almost to fast. You get jolted around pretty good! But I've pretty much memorized my commuting route to work so its not really an issue. I like the simplicity and weight savings of conventional forks, but like mentioned before, quality suspension forks adjusted correctly for rider weight do work really well.

 

[bikeman242]

I think I started thinking about this after looking at the service expectations on suspension components. I think most air forks are supposed to be serviced (like rebuilt) every 200 hours of riding and that can cost $200 at a shop. That's a big cost factor if you use your bike for real world transportation. I think the bean counters at most ebike companies still want those extra profits regardless of actual merit.

The cost of the servicing interval for a full air suspension on a city/hybrid bike is what I have been going back and forth over. I would also like FS for comfort/safety, as discussed.

Multiple LBS have told me that unless I am regularly riding trails and putting the suspension to work, the only servicing that the air suspensions will ever need is to put air in them. They say in practice I will need to have the suspension rebuilt every 5 years. Obviously if I am popping air on gnarly trails I will need them serviced, but just for city use there will be no need.

What do you guys think about this? Do you really need to get the FS serviced if you are just using for city riding?
I assume that not getting them serviced would void the warranty on the suspension?

 

[hewstigator]

i only do city riding and haven't done any service on the suspension of my old full suspension mountain bike - i would say the main symptoms I am seeing are that the rear air shock doesn't hold pressure as long as it used to (also the lock-out is more of a partial lock-out now) and the front damped spring shock "sticks" a little bit in the neutral position...?

 

[hewstigator]

PS re: safety, i would say that the FS does help the bike feel more stable over rough spots / washboard surfaces but the way my rear panniers are attached to the rear swingarm, all of the wagging / swaying when i hit a larger bump really takes away from that solid grip feeling... part of the problem may be that my front suspension only bike has the rear panniers stabilized by a bottom clip, but on my full suspension bike, the rear panniers (thule pack & pedal rack with some thule panniers) are only marginally stabilized by bottom magnets

 

[Alaskan]

To the extent that a suspension keep your tires in contact with the road, a suspension provides obvious safety advantages. Increased contact will reduce braking distance as well as increase sure footed responsiveness in turns. The rougher or more uneven the road surface, the more dramatic this Improvement will be.

Another less obvious advantage what's up with a full suspension the rider will not bother avoiding imperfection in the road that would lead to jarring discomfort and instead just ride right over the obstacles. This leads to fewer sudden, unexpected moves by the rider providing more predictable behavior for drivers in the rider's vicinity.

 

[Browneye]

IMO, speed is a far greater factor. Faster = greater collision danger, simply because things happen faster, and greater chance of injury if you do crash.
Some suspension might keep control for a hard obstacle, so in a sense potentially yes, but slowing down and steering around the obstacle is of far greater benefit and safety.

 

[nublar]

Yes but it must be tuned to the road and the rider's weight. I think most of the cheap stock suspensions that come with ebikes offer too much travel and not enough dampening for the road. Also, I think most ebikers are unaware that the air/spring dampening must be adjusted and that suspensions need maintenance typically every 250 to 500 miles.

 

[Alaskan]

Ye speed is a critical factor so being able to reduce that speed in the shortest distance possible is important. If your tires are being unweighted by agitation from road imperfections, braking distance is lengthened.

This thread is about full suspensions on the street, not mountain bikes. When a bike is used primarily on the the road, suspension maintenance intervals are greatly extend versus those on a bike that is ridden through mud, sand and water. And yes proper adjustment for sag and rebound are important if you have a full suspension.

Riding over 7,000 miles this past year, mostly on the road with full suspension class 3 bikes, I can definitely say that I only bother avoiding the deepest potholes or thicer tree limbs, Small branches (less than 2" diameter), and other flaws in the road surface that I would have avoided on even a hardtail with front fork, I just roll over without changing course. Not making sudden, unexpected jukes and jerks make me a more easily accommodated fellow user of the roadway.

 

[Ken M]

It seems a lot of urban riders have read about the aspect of a full suspension bike keeping the tires of a mtn bike in better contact with the ground and improving performance. Somehow that is being correlated to a belief that a suspension is safer. I rode over 6,000 miles one year and I rarely encountered an obstacle that I felt was more of safety risk if I didn't have a suspension.

I started this string because I wanted to see if marketing has really influenced how we view suspensions on street bikes. Some consider the European riders more "knowledgeable" about biking and I think both front forks and full suspensions on road bikes are far less common than in the US.

I understand that a suspension is a more comfortable, but I really really doubt that there is a tangible safety difference on the streets.

 

[Alaskan]

Your original question was not limited to road bikes. I have both read about the added safety of full suspension on touring bikes and ridden it, on mostly rural roads, in varying weather, over thousands of miles. If you already thought you knew the answer why did you ask the question? And why did I bother taking the time to write down my answers?

 

[BBassett]

I've read claims that having front or full suspension on a fast urban mobility ebike actually improves safety. I understand that it does improve comfort (although there is a lot of evidence that larger air volume tires in 2" / 50mm widths or wider can provide 70% or more of the vibration and shock dampening of active suspension) but does active supension really make a street ebike safer?

Note: I understand that a worse case direct hit of big pot hole or curb at high speed a suspension may be the difference between a crash or not but I really don't want these extreme cases be the basis of this question.

Both front and rear suspension adds to the initial cost of a bike and increases service and maintenance but I think the industry wants even street riders to believe they need front forks at minimum. I think it's mainly a marketing gimmick but maybe there is a real safety component to the decision.

I believe that my full suspension has kept me off the ground a few times when I would have been testing the strength of my helmet otherwise. Mostly on rough and loose surfaces like washboard roads, but I have ridden over ruts created by tree roots on a bike path at 20+ mph and heard the guy on a road bike behind me slap and then skid across the ground... once he got off the hard surface it was pretty smooth. Would a full suspension have saved him? I bet he wishes he knew if it would have. The tires do of course add to the shock absorption of the bike and the body but even 4" rubber doesn't match ride comfort of a fully suspended bike, let along the added handling ability, even more so with ebikes weighing and carrying so much more and usually at fair speeds. I believe a full-suspension bike has a handling benefit making it safer than a non-suspended bike.

The "marketing" gimmick is in bike manufactures producing ebike with limited power and all their proprietary crap mandating the use of "their" batteries, "their" frames, and guess what... "their" motors. Buy a great bike (fully suspended in my opinion) and hang a mid-drive on it. Here's the bad news, man, you're still going to hit the ground, perhaps not as often but without a doubt.

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[Ken M]

I believe that my full suspension has kept me off the ground a few times when I would have been testing the strength of my helmet otherwise. Mostly on rough and loose surfaces like washboard roads, but I have ridden over ruts created by tree roots on a bike path at 20+ mph and heard the guy on a road bike behind me slap and then skid across the ground... once he got off the hard surface it was pretty smooth. Would a full suspension have saved him? I bet he wishes he knew if it would have. The tires do of course add to the shock absorption of the bike and the body but even 4" rubber doesn't match ride comfort of a fully suspended bike, let along the added handling ability, even more so with ebikes weighing and carrying so much more and usually at fair speeds. I believe a full-suspension bike has a handling benefit making it safer than a non-suspended bike.

The "marketing" gimmick is in bike manufactures producing ebike with limited power and all their proprietary crap mandating the use of "their" batteries, "their" frames, and guess what... "their" motors. Buy a great bike (fully suspended in my opinion) and hang a mid-drive on it. Here's the bad news, man, you're still going to hit the ground, perhaps not as often but without a doubt.

Google Photos

Home for all your photos and videos, automatically organized and easy to share.

photos.google.com

Ride safe.

I did limit this to road riding safety impact of a suspension vs rigid. I do agree that handling is improved if the surface is rough enough that the tires loose contact with the road but probably pretty rare.

It is sad that ebike companies put so much effort into schemes to make their ebike systems proprietary instead of innovating. Chalk that up to bean counters running the show.

 

[Ken M]

of course it does keep you safer.

motorcycle manufactures have invested tons of money on R&D for suspension, and electronic suspensions do pretty good job keeping the bike stable.

I imagine this theory will also apply to ebikes.

Let's limit the assumed top speed to 55kph / 35mph on any bike and does a suspension really quantifiably improve safety.

Keep in mind that there are some hard tail motorcycles. Also keep in mind that pro racers will casually hits speeds over 70kph on decents and they have super thin high pressure tires and no suspension.

 

[Alaskan]

Let's limit the assumed top speed to 55kph / 35mph on any bike and does a suspension really quantifiably improve safety.

Keep in mind that there are some hard tail motorcycles. Also keep in mind that pro racers will casually hits speeds over 70kph on decents and they have super thin high pressure tires and no suspension.

This is getting ridiculous. Keep narrowing down the question, to more limited circumstances and the answer will still be the same. If your wheels are on the ground instead of bouncing around, you are safer taking a turn and your breaking distance will be shorter...THEREFOR YOU ARE SAFER. What part of that doesn't make sense to you? I am done here.

 

[Ken M]

This is getting ridiculous. Keep narrowing down the question, to more limited circumstances and the answer will still be the same. If your wheels are on the ground instead of bouncing around, you are safer taking a turn and your breaking distance will be shorter...THEREFOR YOU ARE SAFER. What part of that doesn't make sense to you? I am done here.

My question was "Does suspension make street riding safer???

I honestly didn't change the context. I understand it's at minimum subjective even if there isn't any way to quantify control levels on the street with and without suspension.

I'm sure you would at least agree that OEM bike manufacturers want as many customers as possible to believe that they need a full suspension ebike even if only urban street riding ... more upfront cost and more downstream serviced costs. I just wonder if there is a tangible safey difference because the argument seems to go back and forth from safety driven to comfort driven. I'm not trying to upset anyone.

I've been hammered on this forum for suggesting 20mph assist limits are too slow for practical urban mobility.