Building a 60mph electric motorcycle on a 26" bicycle frame

[dogman dan]

Nobody's offended bro. I hope we didn't run you off. ES is just a bit of a shark tank, and most of those comments meant well.

Nobody want's to say, go for it, then hear about how you ended up in hospital later.

VERY GOOD ADVICE, to work up to it gradual. People get into the 40 mph club on incredibly shoddy bikes and survive it. Once you go 40 mph carrying the extra weight on the frame you have in mind, you can decide for yourself what upgrades are needed to go faster. People say racers go 60 mph. They do, but they aren't carrying batteries.

My fast bike was built for the smooth racetrack, with no suspension. At 45 mph, a manhole cover was quite an experience on test runs.

40 mph club can be done for about $1000-1500. 60 mph is another story. mostly battery costs, and deciding if you trust a bike tire at that speed. I've worn out tires on my track bike in 45 min. Looked good outside, inside was shredded from overheating them in corners. It's stuff like that we are warning you about.

 

[MadRhino]

Even MadRhino would have had an easier and much cheaper experience if he'd started with a 125cc motocross bike instead of a pretend-motocrosser DH bike.

Easier and much cheaper yep, but not half the fun. :wink:
My bikes don't pretend to be motorcycles, this would be raising the motorcycle experience to a level its never been.

 

[speedmd]

At 45 mph, a manhole cover was quite an experience on test runs

Hi dogman

Were you clipped into the pedals/ able to bunny hop the bigger obstacles. Have to pay close attention for certain.

IMO Light weight is key here for a hill climb machine even if it is a bit scary to ride the few miles. Good point on the tires/ tubes. Tubeless may be a good candidate for the higher speed setups if you can keep the tires on the rim when they deflate. My old campy neutrons are near impossible to get tires on and off of so they would be a good choice also. They held up to the hell of the north regularly with the bigger riders so smooth roads should not be a issue for them.

Guys forget that a pedal bike sprinter is pulling, pushing and tugging for all he is worth (and most are some pretty tough fellas) and the bike is built for stiffness/ not just strength. They are in general way over built for smooth running high rpm motor power with a relatively stationary rider /battery loads within reason. Interesting exercise.

 

[MadRhino]

So I guess I can't use a Raleigh steel bike frame for this one, eh?
How much would a 60mph build like this cost?

You can use any frame, and make it as cheap as you want. It is not the target speed that cost a lot; it is making it a good, safe and reliable bike for that power and speed.

 

[cal3thousand]

I still want to know what's the fastest speed that 3wheels1life has fallen while moving.

If I think about it myself, it must have been only between 15-18 mph and I was clotheslined by a nylon coated steel cable at the age of 9. I can't imagine falling off of a bike at 60mph.

 

[neptronix]

I'm still really really effed up from a 20mph fall.. two shoulders, one wrist, and two knees will never function the same as they used to. 60mph on a bike is fun once or twice, but without motorcycle gear on while riding, you are most likely dead or vegetative after that fall.

Looks really weird for someone to be on a pedalbike with motorcycle gear on, lol...

 

[hjns]

here is my 0.02

In order to build a sustainable ebike for 60mph demands a lot of understanding of all the parts and a specific purpose in mind. If you are really only going to do 60mph on a supersmooth flat race track with maximum range of 10miles, then that will require a completely different setup as compared to a 60mph capable mountainbike that will get you up and down the same downhill track in the alps. The last one would require a full downhill setup with an enormous battery (think 2kWH) to get any acceptable range (think 20miles), whereas the first one could be a nonsuspended lightweight racingbike (think 1kWH battery). The racingbike would have completely different issues with heat, whereas any hillclimbing goat would need an extensive cooling solution.

Anyway, I went with a 45mph bike, based on an XC FS frame, various front forks with increasing quality, and a cromotor + 20S + 18FET. I get nowhere near 60mph, and wouldn't dare to do so on this bike, even though I am confident that the wheels will hold (laced myself). It is really the frame and the braking distance that worry me at high speeds.

 

[hjns]

Looks really weird for someone to be on a pedalbike with motorcycle gear on, lol...

Yes it does. I wear a full padded motorjacket with motorboots and motorgloves. People look at me and laugh at me. Their laugh changes to admiration once they notice my acceleration, even on my temporary citybike (20S + Lyen sensorless 6FET + HT3525). I don't care too much, in the end if I fall off at 30mph, I have at least some basic protection.

 

[speedmd]

Lots of very good points guys, but it is not speed that kills, it's the impact/ sudden stop. Agree, rough terrain, you are crazy to want to ride a rigid framed bike at high speed. Even if relatively smooth, it is a balancing act /tradeoff with weight /control/ pedaling efficiency. Not a cost factor. We are not going cheap. May build a new custom frame if a prototype / mock up shows promise. Mission is to go for gold in the feather weight class. No prizes for the losing reliable everyday bike. Will see how it develops based on what may fit the build that is available.

It does look kinda funny, but not a good idea to hit the salt at 150mph in your lycra shorts.

 

[cal3thousand]

You're right, it's the deceleration that must be controlled. But at 60mph, the kinetic energy that you need to dissapate is immense. Bike tires are generally not made to handle those speeds for extended periods, so scooter/motorcycle wheels are often used to mitigate that. If one insists on using a bike to get to 60mph, at least upgrade the friction materials to handle those speeds.

 

[Dauntless]

take an aluminum can

Funny one. What is the safety factor in this example. 0.1-.2 or so with my weight possibly if you have good hard thick aluminum can. With Chalo..... :lol: :lol:

What is the safety factor in a standard road frame. . . . . Aluminum frame, possibly 1.25 SF. Forks / steerer tube ---1" size. Newer 1.125 / 1.5" fork steerer setup would be better. Also suitable would be a heavier large tubed carbon frame, but the failure mode is a bit concerning. :|

You left out the number one thing I'd be concerned about --- THE WHEELS. Letting go at speed because the precarious balance that holds them up becomes. . .INSULTED!

 

[speedmd]

You left out the number one thing I'd be concerned about --- THE WHEELS

I hear you! I was just thinking on this and I saw your post. Clearly, the 16 spoke front wheel is out. Just the weight of the battery/motor is enough to scare me with that. The campy neutron front with 22 spokes would be strong enough for a real light build. The older eurus g3 rear possibly. Most likely a set off the older classic with a full complement of spokes and a heavier rim would be best.

Shopping for the strongest narrow chain I can get.

 

[veloman]

Why are you even considering any wheel with less than 32 spokes? Many roadies ride and race on standard 32 spoke wheels. Dropping 10 spokes off a wheel is not going to do anything for efficiency or speed on an ebike. Maybe 0.2mph faster.

You're right that a strong sprinter is going to torque a bike frame way more than a 2kw peak motor. It's all about torque. And a human body puts out way more torque. The motor has the RPMs, so it's power can be much higher.

You would be best running a large outrunner RC plane motor with a single direct chain drive. #25 heavy duty chain would be fine for 2kw likely. You might even be better off using a 6 turn Mac rear hub motor in a 700x30 wheel. 72v would give you 60mph on a downhill (or with enough amps) Better get ready to do your aero tuck and probably do some fairing mods at these speeds. If you want 60mph sustained, you will need a DD for sure. I'm not sure if a controller would even be able to handle the rpms of such speed on a geared motor.

I just don't think 50+ is a good idea on a road bike. I've done 60 down some hills, even 70 once, while drafting. You WILL catch air on the slightest bumps in the road. A 40mph road ebike is pretty realistic and lot safer (still not 'safe').

 

[John in CR]

A 60mph bike can be safer than Chalo's 20mph pedal bikes. If you lower it and extend the wheelbase then it can be just as safe as a motorcycle, because what you might give up in frame strength you can make up for in agility. The pothole point is without merit, because if you're unable to avoid potholes on any 2 wheeler, you're going too fast for the conditions or not paying close enough attention, and not paying close enough attention is the leading cause of injury.

 

[speedmd]

Why are you even considering any wheel with less than 32 spokes?

It will depend on the weight of the bike, certainly. Hub motor is not in the cards on this build. Looking at possibly as much as 8- 10kw into the chain. :lol: One goal, climbing speed. Not building a beach cruiser. If it is scary, so be it. Been there. I can hop a still see well enough and know how to handle the rough patches well enough to give it a fair ride.

The more modern campy factory wheels are very sturdy. More so than many of the 32 spoke classic wheels I have used going by my luck with them over many thousands of miles on very rough roads. Steel spokes I think best on conventional wheels. I am light so I have some safety factor. Some other choices if I can get some loaners. :wink:

 

[dogman dan]

John is the one who has done it the best, and the cheapest. Longer wheelbase is definitely the starting point for above 40 mph.

In case you didn't know, a TDF race bike does have a longer wheelbase than typical entry level mtb's.

What Cavendish does not have on his bike, is a big ol honking heavy ass battery frocking up his bike's handling, and causing him to get the tank slappers.

A good stiff cromoly frame, or better than normal alloy frame can be plenty strong. The question is, how will it handle bumps when fully loaded down with enough battery to haul ass for very far. That's what I meant by the manhole cover being quite an experience at 47 mph. Bunny hop it? Oh right. I bunny hop all the time on 70 pound bikes.

Do you have experience with a 40+ mph ebike Speedmd? It's just different than descending big hills on a good racing bike. It's all that weight of big motors and big batteries that makes tires and rim flex not enough. And.... I sure as hell don't weigh 115 pounds like when I rode a race bike like a maniac down big mountains. At 20, I could fly down Emory Pass at 50 mph.

HPC is introducing a new bike, said to do 60 mph. I moved the thread to for sale new.

 

[speedmd]

Do you have experience with a 40+ mph ebike Speedmd?

Hi Dogman

Funny you should ask. I took my gng cdale ebike down a few of the good road down hills lately. It tops out motor wise around 45 on the descents under power. Changing the gearing at the moment to give bit more top end, to possibly 55 plus on the descents under power. One of these hills has a 50 plus MPH section going well over a mile "just coasting" and is a very broken up road. You have to pick your lines so not to rattle everything around a bit. And yes, I can hop the sub 55 pound cdale and it is completely unfazed at the speed It is coasting up to of around 53-54 mph. With the gearing change and going to 18s I certainly will not be holding it wide open for long there as it twists and turns a bit too much.

It may not be worth loosing the 2 inches of suspension something like this bike has in trade for losing 10 -15 pounds of weight. Certainly, every pound you take off for a event like pikes hill climb for a example (some 5000 feet of climbing) is a loss of 5000 pounds feet of energy required. 10 pounds less, is 50,000 pounds feet less energy required . 20 pounds is 100,000 pounds feet less. Hard to make that up.

 

[John in CR]

Bunny hop it? Oh right. I bunny hop all the time on 70 pound bikes.

A truck forced me toward a large diameter pothole of unknown depth (unknown at the time due to water) with no way to avoid it at about 40mph on a 90lb cheapie dual susp, so I bunny hopped it with 0 experience in bunny hopping. I guess that's what you call it anyway, since all I had time to do was lift myself off the saddle and gave the pedals a little jump just before the hole. I'm sure I got zero elevation, but I cleared that hole as smooth a silk like it wasn't even there. A couple of days later I saw the pothole dry and it was steep and deep, so just plowing over it could have been really bad.

The point is that even a fairly heavy ebike can be so much lighter than a motorcycle that we can pull off evasive maneuvers that are impossible on a motorcycle. Motorcycle manufacturers have to build motos for unknown JohnQ Public to ride without using their brain and do almost anything to it without it falling apart.

When building something for ourselves, the nature of our riding determines how our ebikes need to be built. Guys riding with reckless abandon obviously need a stronger frame and components than someone sticking to the streets and avoiding hazards through the use of strict focus, riding techniques, and knowledge of the roads they ride. MadRhino is able to go off road and ride in a manner I would be terrified to try, and do it with quality downhill bicycle components. For a bike to abuse off road I will have to stay mostly away from bicycle stuff though. That's mostly because I'm not willing to do the inspection and maintenance required, and I'm not willing to spend the big money for components and parts either.

OTOH I'm able to ride an ebike based on a bicycle frame that is capable of 100mph, and do so with confidence that I am safer than the overwhelming majority of people on the road with bikes, motos, and cars. I don't place heavy reliance on the strength of my bikes, because I put what's between my ears to full use. The roads I ride aren't perfect, but the single track routes I take using a full lane of width result in a near perfect surface traveling from point A to point B. My bike frame may be a built for DH/freeride use, but I don't have any delusions that I could just plow through a giant pothole at 60mph without risk of the tire or fork collapsing, or the frame snapping off at the headset. To stay safe I simply make it virtually impossible to hit such a pothole at high speed instead of building the 200lb bike required to take that abuse.

John

 

[dogman dan]

I'm not sure how I'd bunny hop a bike without being strapped or clipped into the pedals.

Definitely know how to float the front tire over a bump or hole, It's hitting the unsuspended back wheel on the manhole cover that tested my frame and rim.

Pardon my question, but we do get folks here who rode fast on light bikes, who think it's the same as with 30 pounds of battery. It's clearly different. My race bike was loaded to the gills with battery, because the race I was headed to was 12 miles long including the pre lap and the finish lap. It was definitely overloaded, like a bike made to go 60 mph for more than 10 miles would be. Hitting the same pothole with 10 pounds of battery on board was not such a big problem.

This is the point I'm trying to beat to death here. 60 mph bike? Sure, especially for a 5 mile blast. 60mph for 30 miles, a big problem for nearly all bike frames. 60 mph on the flats with no tailwind takes some big battery. I'm just trying to say, choose that frame wisely for a 60 mph ebike. Cheap or expensive, it must be stiff and strong or you get the tank slappers. An 80 buck steel beach cruiser might be stronger than a very pricy alloy frame.

This is why my long distance bike is a longtail cargo bike with full suspension. It handles 50 pounds of cargo better than a stock MTB. It can carry 45 ah of 48v and do 30 mph without that sketchy feeling I got on short bikes. Again, longer bikes than typical child size bikes from walmart work best at speed. I hop up curbs with it slowly, but with no fear at all I ride off tall curbs at 30 mph on it. I could find out what it's like at 50 mph with a quick controller swap. But I just don't need 50 mph on the streets, nor is it legal where I live.

 

[speedmd]

I'm not sure how I'd bunny hop a bike without being strapped or clipped into the pedals

Yes, LOOK keo carbons. All my bikes share them for road use. No doubt, it is near impossible without something like them or a rigid peg area to squeeze against and pull up on. I come from a mx racing background and lots of years of trials riding. I am not seeing this from a noob position. I could ride the old trial bike on one wheel indefinitely and bunny hop the 190+ pounds of it over some amazing stuff, so the 50- 70 pound bike is more like a pedal bike in comparison. Certainly a great exercise thinking through a no compromise feather weight build.

Wheel base certainly makes things less challenging at speed. A few years back I ran down a long steep grade on my roller skates with a friend on his bike, as he did not believe me. Told him I was skating down this hill at something like 50 mph. This is on 12.8" wheel base 5 wheel speed skates. I could do it as I told him, as I know speed well, and was doing this weekly as the newly paved down hill was part of my training route. In lycra no less. He stopped questioning me when I dropped him going over 45 MPH and me in a full tuck. He was a timid descender. I know what your thinking and Yes I have hit the ground at speed.

Some of the dumb things you do when young I guess. With 40 some odd inches of wheel base I don't see it as a issue for a short race scenario at 60mph.

cheers

 

[rafeh1]

What's the highest speed you've ever fallen off of a bike

Does that include a motor bike Been there on all types.

I want to build a super fast ultralight 700c ebike. Smooth roads only. Full on, w/ friction brakes, light 25mm road tires /clincher wheels, tt clip on bar set up. Max 40 pounds.

And yes, I am wanting 60 PLUS. Seriously. Will fatten up the tires only if I absolutely have to. Just want to see how it will climb. Will keep it in the garage on windy days for certain.

I built mine as a single speed 700C I got 48lbs, 34 mph and 25 mi range on Oetoma motor and 48v 10 ah lithium ion battery

http://www.youtube.com/watch?v=u-TovKcOAaE

 

[gaf]

Hi everyone,

Do you have any suggestions for building a hub motor powered electric motorcycle on a 26" bike frame?
Legally, it wouldn't be an e-bike. I'd like it to go 60mph.
Any advice you have is appreciated.

-3wheels1life

Yawn. Stunts are totally lame. It's what you can do every day, comfortably, that is what impresses me.
You're on your own if you attempt this (obviously). No one wants to take any responsibility for what happens to you when your shitty front tire blows out and you skid 100 ft in jeans a cotton t-shirt.

 

[speedmd]

It's what you can do every day, comfortably

Hi Gaf

Welcome to the group. We were discussing a extreme build not sipping coffee while reading the funnies. :?

If your in the racing business, I wonder how long before the sponsors/ support goes away while your running extra conservative or for comfort? All about the risk / reward. Even while on the pedal bike doing intervals, hill climbs, or TT's, comfort is not usually part of the top priorities. All things being equal, yes certainly comfort is a plus, but not at the expense of performance in a racing situation. They don't call them pilots for nothing.

cheers

 

[canadianbikeguy]

...crazy death wish, just crazy! Hope you have a good healthcare plan, and a ton of life insurance. Don't think a helmet would help you at all, might as well just do without one at those speeds.

Crazy

 

[speedmd]

...crazy death wish, just crazy

.
Funny one coming from a guy in Canada, bike guy. You must be a import. I have been there many times, and never saw anyone going less than break neck speed on the highways and secondary roads. :lol: Even on ice you guys drive like 120kmh. Maybe a bit less when the mounties are out. Forget the snowmobilers, they are insane. Even your skaters go 8 second laps/ 45+klmh in short track. :lol: :lol: :lol: