Why are so many trying to chase high speeds? Reality check

[zombiess]

I'm getting a lot of inquiries lately on people trying to go really high speeds on their bikes. Much of this is in relation to me me selling the motors I am and the videos I've posted of me going 50-60+ MPH.

I have several people asking for a 13 kV wind version of this motor and if that's what you want I'm sure Accountant will be more than happy to order a few for me to keep in stock for those who want them, but you have to know what you are getting into.

First of all, let's talk about me for a second and why I'm posting the videos. I'm a speed freak, in general speed does not scare me as long as I trust the vehicle. I own and drive a 3100lb 460+ HP Corvette Z06 as a daily driver, it's slow as shit and takes forever to get to 100mph. My second car which is currently awaiting a new motor is a 2000 Camaro SS setup for street strip. It's turbo'd has a trans brake and on the race track does 0-100mph in under 6 seconds. On the highway it will usually break the 275/60/15 Mickey Thompson Drag radials loose from anything under 100mph if I don't roll into the throttle, that's right I can and have done 80-100mph rolling burnouts by simply flooring the gas pedal. It has an completely custom well engineered 8 point cage tucked away to prevent the cage from killing me in a low speed collision on the street due to not wearing helmet and suffering massive head trauma. It will go 60-120mph in a little less than 6 seconds with good traction and I'm able to beat most liter bikes I race on the highway because the odds are in my favor with my power to weight ratio and the fact I don't have to shift. I've been doing this for many years. My first street bike was a 91 FZR 1000 which for a few years was the fastest top speed bike available and capable of 170mph which I've done on GPS once. I've also gone over 170 MPH GPS in my Camaro at least twice I just get there a lot faster than a motorcycle does.

Now, lets get back to bicycles. Most bicycles aren't engineered well to handle speeds above 30mph which means you need to start modifying them to make them safe. There is a huge difference between 30mph and 40mph. I see many people on here who want to exceed 50mph or even 60mph which is fine, but you better damn well know what you are doing before you slap a massive controller, battery and motor on your Walgoose bike with questionable torque arms, poor suspension geometry and inadequate brakes. I know many like to cheer that someone is a man for going some stupidly high speed with no brakes or something else just as stupid, but take a step back and think about it. Going over 40mph puts you into motorcycle territory. Do you have friends that ride motorcycles? If so ask how many of them have had wrecks, massive hospital bills, metal screws and plates in their body. If you ride on two wheels it's not a matter of if you fall it's a matter of WHEN! If you can ask your friends great, but I know some I can no longer ask because they are dead due to being reckless, some at speeds as low as 25mph. Some their own faults, some the fault of another. Most were riding race class motorcycles with extremely good handling and the ability to avoid bad situations, but a machine is capable of nothing without a driver.

Before you dive into a project targeting high speeds on a bicycle please think about what you doing and if you and your machine are capable of doing what you want to do. There is nothing wrong with setting a limit. If you search through my post history you'll see I struggled with the decision to go high speeds for a long time, but I finally gave in. I'm friends with some mechanical engineers and fabricators and know quite a bit myself so I had a general idea of what was required to attain my goals in a relatively safe manner and your bikes suspension geometry is very important at speed as well are it's brakes. Do you know how to wire and work around high voltage safely, 100V from a LiPo pack can kill you if you aren't observing proper safety. I spend many hours making most of my wiring harnesses because I'm worried about that much voltage being in such close proximity to my body.

Now let's talk about cost.
Let's say you decide to go ahead and you manage to aquire something like a 13kV version of the Cromotor or a Crystalyte 5402.
Are you ready to spend $400-$1000 for a controller, how about another $1000 on batteries and wiring. Is your bicycle safe, if not, what's it going to cost to upgrade it to the point it is safe. Do you have a full face helmet/jacket/armor/motorcycle gloves? If not, you need them.

Just for an example here is what I'm simulating for the 13kV motor I'm going to own myself so I can test out my high voltage water cooled power stages.

I'll use a 21" tire and assume a 30S2P NanoTech pack as I own one of these now. Fully charged that's 126V@12AH. I'll use 9AH as I never fully discharge the pack.

My best guess is that this motor would get my current bike to about 85mph while drawing 206A of current from the battery. At this speed I have an estimated range of 3.8 miles. Personally I don't think I'd do this speed on my current bike. Even on 100V it would still be capable of 70mph and need 145A of battery current with a range of 4.5 miles.

Many want to put motors like this in 24" and 26" wheels because 20" doesn't give enough ground clearance, bad idea unless you have a massive controller. At 100V in a 26" tire you should be able to go 80mph if you can supply the 225A it needs for all of 3.3 miles.

FWIW, I believe once I have the geometry fixed on my new bike with a longer swing arm I'm going to be able to take my z06 from a dead stop in a drag race to 50mph with my 9.3kv motor, but my drop outs better be really strong to take that kind of load. I'm more an acceleration than a top speed guy. I love that free fall feeling I get in my stomach when I get a hard launch which is about 0-60mph in 1.9 seconds or traveling from 0-60 ft in 1.55 seconds based on my drag racing experience.

If speed is your drug I'll happily be your dealer and help you feed your addiction, but I want you to think about what you are doing before you just jump into going fast. It's all about risk / reward. Even on my bike that can go 60mph I rarely exceed 35mph when I ride it because there is no need for it except maybe for a quick blast on a safe street if I feel like it. This bike will also be raced though so it has another purpose.

Don't take this thread the wrong way, it's not meant to be a lecture. It's meant to make you think.

The undead ZombieSS

 

[Spacey]

Top advice, after braking both my arms in a bad way a few months before Christmas I have seriously slowed down and taken things a bit more easily. Nice to have the power when it's there but it is addictive and yesterdays high is never satisfying enough today.

I have decided that push bikes and good ones at that are good for 30mph average speed...next step up for me is converting a Cagiva Mito 125cc sports bike because it is designed for those higher speeds and can brake etc.

 

[E-racer]

Great write up. I agree with you fully. IMO if you have any brakes other than nice hydraulic disks I would never recommend speeds much over 30 mph. I have melted v-brake pads riding an XC bike downhill with no motor. I do feel that most DH or freeride bikes are plenty capable of 45+ mph. It is somewhat common for this speed to be achieved while bombing down melted double black diamond slopes. With properly setup suspension these bikes are 60mph safe on the road.

 

[Ykick]

It's about the right tool for the job. For my purposes, I want speeds and rough specs like a high performance pedal only bike. I wanna be able to lift the damn thing up stairs or in/out of racks and bicycle parking infrastructure. I want the wheels to survive rough roads and heavy loads.

It's my commuter, I don't need to go more than 20MPH on bike paths. 'sure, that little extra above 25MPH is nice in traffic but it's so easy to forget these are just bicycles. IMO - once weight surpasses 60lbs and speeds into 40-50MPH that's no longer a bicycle. That's awesome and fun but doesn't make it a legitimate motor assisted bicycle.

 

[ohzee]

Yea good advice.. Myself I am happy hitting low 30's.

It's just amazing to me these electric motors can push so fast..

Thanks for taking the time to possibly save someone some pain.

 

[Wurly]

Camaro sounds interesting. Whats your best ET?
I'm into dragracing, i had a 68 Dodge R/T that ran 12.09s @118mph. My 1200 suzuki ran 11.4s@112mph. The fastest thing i was ever part of was an AA/FA we ran with a few friends 6.89secs @199mph (used to get loose at the top end)......all this in the UK.
Top speed for me now is 23mph on a eletric powered bicyle, but my new machine should hit 28mph....wow!!!!

 

[MadRhino]

I am after performance, but not high top speed. Let's say, riding 40+ Mph on a mountain single track with obstacles and big trees everywhere around is fast enough for anyone. Once a bike is set to do above 40 and has good acceleration, I'm happy with it and looking more toward improving weight, handling and suspension tuning.

Then, any of my bikes could safely ride 100 Mph if I was after speed, for they are very stiff frames with perfectly tuned high end components that handle as well, if not better, than the average motorcycle. Yet, most of my riding is either in the mountain trails, or on the streets of a crowded city. In those conditions, the speed that I can achieve is more about the bike's overall performance and handling, than it's top speed capability.

 

[Hugues]

Acceleration is what I like , more than speed.
Around 50 km/h I stop.

But a clean, firm, non-stuttering, linear, noiseless acceleration , the kind you have when the batteries are fresh and the bike is nicely tuned, this is the ultimate pleasure for me. I never get bored of it.

Especially if the acceleration takes place in a narrow trail, the feeling is even better.

Acceleration.

 

[zombiess]

I've been down this road and written a similar tale of caution on a car forum I'm on since I have the thirst for speed. Luckily for me I didn't have the funds at the time to get the results I desired all in one shot because I probably would not be here typing this right now. I started off with relatively fast cars in the 300 RWHP range and moved up from there, but I did it in steps and as I did it, my skills and adrenaline rush dissipated, time for more power. Over the years I went from 300 RWHP cars to one that made 750-800 RWHP. It takes time for your brain and reactions to adjust appropriately to what's going on. I'm using cars for an example here because I'm very familiar with them and it's the route I first took. If I took your average driver and put them in a 300 RWHP rear wheel drive car and said drive around this race track as fast as you can, pretty much everyone would spin out. The reason is their body is not able to process all the input it's getting fast enough and they get an adrenaline rush. This usually causes tunnel vision and often the involuntary reaction of tensing your muscles. This is exactly what you don't want to do in a panic situation. Many people are unable to regain control of their car if the rear end skids out in a smooth manner and over correct because they aren't familiar with the limits of their car and how it will react.

I've looped my bike a few times in the beginning when first getting into high power because of the involuntary grasp reflex when the front end came up faster than I expected causing me to give it even more throttle. Done it 3 times at low speed several months ago, but now have more control when it does it and can back off.

Now take corners out of the equation and put them into something like my really fast car making over 750 RWHP. It's super easy to go fast in when everything is perfect, just point and press the throttle, pull back on the ratchet shifter at 70mph, click into 2nd and you are good until the next shift at 130mph. Now if the rear end starts to get out of shape and you are going fast you can't just instantly lift off the throttle, that results in what can become a very bad situation called snap over steer caused by the weight shift of the car. Seen plenty of cars go into the wall from drivers doing this. No one is immune from making mistakes no matter their experience, it's always best to work up to your goals gradually to give your senses time to adjust. Just like if you get into downhill skiing or mountain biking. Your first trail isn't a double diamond unless you want to get hurt.

I know many here ride motorcycles but I'm sure most of them will agree a 50mph bicycle reacts very differently than a 600-1000CC sport bike in just about every single category... except fun, the ebike is usually more fun than the motorcycle for some reason.

Wurly, cars best run was 10.001 @ 135.x (1.50 60') with many many 10.33 and under passes made on poorly prepped track (street night) and 3000-8000 DA. Car is setup for street so it wasn't as quick in the quarter as one would expect. Th400 going through traps in 2nd at 135-136. I used 3rd as overdrive for the highway, 2.75 rear gears 9", 28" tall tires. Just a gear swap to 3.25's on a good track would have been a whole new world but I drove the car about 100 miles per week on errands.

So in conclusion if you want to go fast, go fast, but have a great deal of respect for what you are doing and make sure you aren't over exceeding your own or your machines capabilities. I know from just changing my race bike over the last few months going from a rear shock that was rebound only adjustment to one that gave me full rebound/compression/air spring rate adjustment made a noticeable difference when riding at high speed, one of the reasons my videos are pretty smooth, I assure you the roads were not a smooth as they appear in my video.

 

[neptronix]

Well stated, zombiess..

I would say most bicycle bits are good up to 30-35mph. The cromotor will propel you to speeds far over that; it will require motorcycle/scooter grade brakes and an extended swingarm to prevent the ensuing wheelies. It will likely round out rear dropouts without having proper torque plates in seconds.

This motor is not for regular bicycles. To run it on a regular bicycle, you would need to run it at a power level that is far under what it's capable of producing.

 

[zombiess]

Well stated, zombiess..

I would say most bicycle bits are good up to 30-35mph. The cromotor will propel you to speeds far over that; it will require motorcycle/scooter grade brakes and an extended swingarm to prevent the ensuing wheelies. It will likely round out rear dropouts without having proper torque plates in seconds.

This motor is not for regular bicycles. To run it on a regular bicycle, you would need to run it at a power level that is far under what it's capable of producing.

Actually that's exactly what Greyborg had in mind when they started with these motors. Run them well below their capabilities so you can't hurt the motor and have great torque for climbing steep hills without having to worry about overheating the motor causing damage. It's how they run them on the Greyborgs. It's just that here on ES we have a lot of speed freaks. It's all to easy to lose sight of what your main purpose of your ebike really is. I carry a much larger pack than most with 30S3P 125V 15AH and if I run at 40mph continuous I can go 16 miles leaving some left in the pack for safety, slow the speeds down to 20mph that rage goes higher than I'd be comfortable riding. The motor is kind of like a sports car. It's capable of producing awesome acceleration and speed, but the reality is very very few of us will ever ride it at it's maximum all the time unless it's put into a race bike and you are on a race track. As I've mentioned several times now, I rarely ride over 35mph due to the risks involved, just like with my cars I rarely drive over the speed limits, but I do enjoy some on ramp fun every now and then.

If I made a video of a 15 mile loop I like to ride you guys would fall asleep because there is only one section I go over 35mph on. The majority of the ride is done at 25mph or slower. I think my average speed on that ride is about 18mph.

 

[StudEbiker]

I agree with this post. I've been doing this e-bike thing for close to four years now and still feel 30 mph is as fast as I would want my bikes to go under power. I literally cringe every time I see someone new to the board saying they are planning on running 72v+ lipo as their first bike and follow up with some ridiculously nooby question about lipo like, "Which leads are the power outputs and which ones go to the charger?"

One fact of life that I have accepted is that "the greats make it look easy." Just because someone else makes something look easy does in no way shape or form mean that it is going to be easy for you or me. That's why they are the greats....get it. :wink:

 

[John in CR]

While I agree with most of the stuff, regarding brakes regen braking can make up for an awful lot in the mechanical brake department because regen leaves the mechanicals fresh and cool. Car brakes don't handle the downside of mountains here very well, and I couldn't imagine no regen to keep the speeds down.

Regarding speed, I never had a superbike but the motorcycles I had I never really enjoyed riding above about 50mph. That makes my 55 and 60mph ebikes just the ticket. They're all on just 20s, and despite having capacity to go higher I never have other than the geared down 9C run as a mid drive at 30s.

Acceleration is a different story, and while 20s is enough in terms of max speed with my motors, the closer I get to zero seconds for a 0-50mph time the better. While some gas drinkers I've been in can outdo what I've done so far with the electrics, the near silence and no shifting to interrupt the continuous thrust of an electric is a truly unique experience that is the future.

Maybe LFP with his 100 manhours to set up super controller has a bike with mild manners when you want it, and crazy performance just by being more aggressive with the throttle, but otherwise we've yet to tame our beasts. In addition to better/cheaper batteries becoming available in 2012, I'd really like to see more effort made in the direction of better control over the high power motors we already have available. We very badly need a throttle response that is more ICE-like.

John

 

[Jason27]

I totally agree that too much speed with an ebike is not safe. I ride at a whooping 25mph and that to me is the safest. Some people on this forum have gotten seriously injured due to speed.

Be careful everyone.

 

[zombiess]

We very badly need a throttle response that is more ICE-like.

John

I have a micro controller and a circuit designed that allows a exponential curve with an added delay to smooth the power deliver to allow less sensitive throttle at the low range for xie chang controllers, just no darn time to build and test stuff right now. Driving me absolutely nuts that I've been home for 1.5 weeks, am still sick and can barely do any kind of work. I can't even ride my darn bike for fear of making the pneumonia worse.

Only thing it hasn't stopped is me bleeding money on parts to complete projects. $480 worth of components showing up later this week. I'm just going to have to give in and pick up the soldering iron, damn the fumes, I need to make some progress on stuff.

 

[ZOMGVTEK]

This guy makes sense.

I generally snap the throttle wide open right when I get on the seat, but I rarely go over 30. The bicycle just gets too sketchy past 30, and nobody really expects that speed on a bicycle. Acceleration is a way better bet than speed, and it gets you in a lot less trouble. About as fast as I would want the bike to go would be 50, and the reason would be so that it gets to 40 faster. I'm very comfortable going about 16-18 MPH, but I never wear any protective gear besides jeans.

The problem is its 'cool' for the bike to go fast. One of the first questions people ask is how fast it goes, assuming I run it wide open all the time. I've lectured people a few times about how dangerous speed is on a bicycle, but I don't think they get it.

 

[rojitor]

Very good advice! I can only say bravo! I agree in most of your points. Now that you are gonna deal the cromotor prople must know what they are getting into.

 

[liveforphysics]

People chase high-speeds on a bicycle, because the thrill is worth the skin and bones (or death).



Everytime before I ride deathbike, I start out by putting on full superbike racing gear, and then I ask myself if it's acceptable to me to die, be crippled/paralyzed today for this ride. If the answer is "yes, I accept the terms", then I ride it, and it gives me amazing experiences that I value more than any physical possessions.

I will be honest with you guys, somedays the answer isn't "yes", and I just take the GSX-R1000 instead, because my nerves just aren't up for a really intense experience, and I'm just not embracing death/pain as much as I should be.

 

[John in CR]

LOL! Maybe that's why I don't have that need for speed. I get the same thrill with greater sensitivity to the outside environment with the only protection aboard lying between my ears, and I willingly accept all associated risks. Over 50mph is simply too windy to be much fun for me. Closed helmeted + riding leathers and armor I think I'd need a hell of a lot more performance for the same feeling, and if I was carving up mountain roads that's exactly what I'd need.

John

 

[kfong]

I'm falling all the time in the trails. Speed is not my friend

 

[MadRhino]

I'm falling all the time in the trails. Speed is not my friend

Those who crash all the time, don't need speed to break their bones.

 

[parabellum]

I made bike (cheep mongoose) reaching top speed of 100kmh because it was my mark, I did few rides to see how it feels. (little scary was the answer , my fireblade feels safer) Now, my highest bicycle speed is limited to 70kmh but 2nd speed limit is set to ~ 60kmh where I nicely cruise at WOT.

In healthy brain, survival instinct draws very defined line in between fun and danger, I try not to cross that line lately.

 

[grindz145]

For people that aren't out for the most high-strung thrill machine, this is good advice.

Even for people that are, there is an entire science to motorcycle chassis design, which you have to start paying attention to when you start to achieve >8kW or so.

Gangster ebikes have their place; in order to push the technology.

 

[oatnet]

I have several people asking for a 13 kV wind version of this motor and if that's what you want I'm sure Accountant will be more than happy to order a few for me to keep in stock for those who want them, but you have to know what you are getting into.

You have a fairly intelligent and experienced customer base here, so I reckon those asking do know what we are getting into. I can see giving this advice to a novice, but remember your audience. Those of us who have been here a while, and built a pantload of 30-50mph bikes in our day, feel the desire for MORE POWER as strongly as ever. After you have been here for a few years, and made a few dozen 9kv crobikes, you too will be looking for something new and different.

For a 30mph-40mph bike there are a lot of lighter competitors, so to justify the extra weight one is either doing hills/dirt, or wanting something faster. IMO this motor started getting major traction on E:S after the posting about the Italian guy doing 84mph on a 13kv wind, so I'm not surprised there are folks like me who want it for speed.

Personally I'd like to see what can be done in a lightweight, solid DH bike, and I'd like to exceed my current 72mph top speed. Plus the 13kv wind is at the sweet spot, fast at 72v for daily use, and scary fast exhibition bike on 144v. 9kv is great for dirt/hills, on the street some folks might get tired of keeping the nose down and opt for drivability. I'd wager that torque loading from the 9kv motor and wheelies is way harder on the frame than exhibition riding at 100mph with 8" of travel.

In other threads I have seen you post that the 13kv wind is a controller killer, but a generic 250a Kelly has already done 84mph on it. Maybe the infineons aren't up to it, but there's a whole world of controllers out there. If one is going to all the expense to buy one of these motors, lace it in moto rims, and build up an extreme frame to handle the high speeds, why cheap out on the controller?

 

[lcyn]

I totally agree that too much speed with an ebike is not safe. I ride at a whooping 25mph and that to me is the safest. Some people on this forum have gotten seriously injured due to speed.
I agree. I am somewhat dismayed by the emphasis on high speeds and overpowering. We are talking about bicycles, modified to utilize electric assist---not motorcycles.
I believe that some of the problems with getting mainstream acceptance of Ebikes is the visibility of overpowered ebikes with way too much duct tape and wires hanging out. A clean low profile build is much more appealing, and more likely to be accepted as a bicycle.
In my community (Fort Collins, CO), ebikes have been banned from using the trail system. Some of the opponents of ebikes have referenced bikes that they saw on the internet that claim speeds of 35mph+. This does not help the cause. I prefer that my ebike be viewed as a reasonable alternative to human powered bikes, and that it be allowed on the trail system. Ebikes that look like a goofy Rube Goldberg invention gone haywire do not help, and reinforce the view that ebikes are not safe or reasonable alternatives to be allowed along side human powered bikes. I believe that <25mph is adequate for an ebike, and pushing 30mph+ is getting to the point that is requiring regulation, as it should. I would hate to see my safe, moderate speed
bicycle regulated because people view ebikes as unsafe. Advocate for ebikes.