# Search for MPH in Topics

### RPM/MPH formula

I'm designing an anemometer with Arduino and I need a formula to figure out the speed at which the rotor turns. I have a rotor with three magnets, spaced 71mm apart, triggering a Hall Effect sensor which the Arduino reads and counts. Now I can't seem to figure out a formula to calculate wind speed from this information. Anybody got an Idea (or the answer?)

Topic by smkoberg    |  last reply

### Fastest you have ever been.

Topic by Yerboogieman    |  last reply

### HOW DO I DETERMINE THE SPEED OF 8 HORSE POWER?

hey guys i was interested in making a motorcycle but i dont know how fast an 8 horse power engine will go. How do i determine how fast 8hp is, infact how do i determine how fast any amount of horse power is. I would like it in mph please.

Topic by pooker    |  last reply

### I'm interested in making a homebrew radar (speed) gun. What are the chances of making this work?

It seems like I could do this using two webcams. Has anyone tried this, or do you have any ideas besides the 2 webcams?

Question by EastDallasMatt    |  last reply

### Question Regarding Measurement of Vacuum Pump Air Flow Using Anemometer

Hello everyone, I am new to Instructables and am loving it so far. I was reading through some literature on a piece of equipment we have at work and it requires 18"Hg @ 25CFM. We have flow gauges at work, so it is just a matter of using one to determine the flow but it got me thinking... What is the most effective method of measuring airflow of a vacuum pump without a flow gauge. All I have is an anemometer, a basic understanding of physics and time. So I came up with this method and am looking for some folks to poke holes in it: I placed the anemometer at the end of a 36" piece of PVC with a 1.6" I.D. sealing the anemometer to the PVC to ensure no air gets pulled around the fan of the anemometer. The other end of the pipe is reduced to a 1/4" line (.16" I.D.) which is connected to the vacuum pump. Turning on the vacuum pump yields a steady 3.5MPH (307.98 ft/m)on the anemometer. Doing the math, I come up with 4.3CFM (307.98ft/m*.013962634ft^2).  Unfortunately, I cannot bring a gauge home from work to compare and I cannot bring my set up, as glorious as it may be. So this is more a thinking exercise. So what sort of accuracy would you guys think this 'rig' has? Can you think of some method for me to verify it's accuracy (or, more likely, lack thereof)?

Topic by mmcdonald6    |  last reply

### Japan to get 217 mph train

The Shinkansen trains in Japan were already plenty speedy at 188 mph (300 kph), but now they're going to be upgraded to 217 mph (350 kph). I rode the train a few times a while ago and totally loved it. The countryside flew by as you tucked into a bento box. It was great and it was so comfortable.Here in California there's a proposition on the upcoming ballot to pass a bond so that we can have a high-speed rail that takes you from SF to LA in 2.5 hours. I don't have a lot of reasons to go to LA, but when I do it would be nice to avoid playing the airport game (everyone loses!) or the driving game (slow down for the car crashes!). To finally get a high-speed train would be a dream.Going metric would be nice, too. 350 kph sounds much better than 217 mph. Link

Topic by fungus amungus    |  last reply

### Measure RPM and MPH on motorcylce with Arduino

Hi all, I have an idea for an Arduino based instrument cluster for my cafe racer (1980 xs400). My question is what kind of rotary encoder I should use to measure the rotation from the cables coming from the engine block and front wheel that went to the original cluster (shown in pictures). I want something that won't break at higher RPMs and is more or less water proof. I have an idea of how to code this on the software level as well, but I'm not to experienced with C/C++ so any help there would also be appreciated. The end goal for this part of the cluster is to output the RPM and MPH to respective WS2812B 5050 LED strips, and possibly a small oLED later down the line. If something could be made more clear on this post let me know and I'll try to elaborate. Thanks again

Question by AedanGraves    |  last reply

### How to learn to drive a car with a mph speedo when all the speeds are kph? Answered

I'm learning to drive in a Morris Mini but the speedo is in mph, when all the speed signs are in kph. Is there an easy conversion I can learn or should I just learn the local speeds in mph

### MIT Unveils 90 mph Solar Racer

A solar-powered car that can go 90 mph? Sweet!MIT's latest solar race car might look like a funky Ikea table with a hump, but don't laugh. It'll do 90 mph and is packed with technology that may end up in the hybrids and EVs the rest of us will soon be driving.The university's Solar Electric Vehicle Team, the oldest such team in the country, unveiled the \$243,000 carbon-fiber racer dubbed Eleanor on Friday and is shaking the car down to prepare for its inaugural race later this year."It drives beautifully," said George Hansel, a freshman physics major at the Massachusetts Institute of Technology and a member of the team. "It's fun to drive and quite a spectacle."Eleanor is slated to compete in the tenth World Solar Challenge, a seven-day race across nearly 2,000 miles of Australian outback. Link

Topic by fungus amungus    |  last reply

### Is it correct that if an 8-inch diameter wheel was rotating at 1,000 RPM then the vehicle would be going 12 MPH? Answered

I'm making an electric mountain board and I am trying to find what gear ratios work to get the speed I want. I don't know if my math is right and I was just checking.

Question by bowmaster    |  last reply

### The Pulse Jet Bicycle that Goes up to 75 mph

Pulse jets are fun to watch and you can get an intro to making one with a jam jar. Make a big one and it can be incredibly freakin' loud. Mount it onto a bicycle like Robert Maddox did and you'll get speeds up to 75 mph as you blast your ears into loose bits of jelly. Link

Topic by fungus amungus    |  last reply

### how can I make a mobility scooter go faster--perhaps to 7 mph?

I have a pride mobility scooter that goes only 3mph--how can I make it go faster--perhaps 7 mph?

Question by arleneharlow    |  last reply

### Why is my Chevy Malibu Maxx Shifting hard?

My dads Chevy Malibu Maxx is down shifting hard. We drive at over 10 mph, then shift it into neutral, and when it drops below 10 mph, it down shifts with a thump. Why is that?

Question by Thelonelysandwitch    |  last reply

### UCs, Toyota Team Up

Toyota has donated two Priuses--one to the Institute of Transportation Studies at UC Berkeley and one to the Advanced Power and Energy Program at UC Irvine--for consumer research and upgraded electric car capabilities. The big news: a plug-in possibility that would allow for pure electric power up to 60 mph, a significant upgrade from the current 30 mph limit (after 30 mph, some gas is needed). A 7 mile commute could be done purely on electric energy, with no gas. Additionally, the universities will do research on people's reactions to charging their car and trying to gauge consumer preferences.This is not particularly new, but it could still be huge for the electric car community. Thanks to Tim Anderson for bringing this to our attention.Link

Topic by joshf    |  last reply

### Zero to 300mph in 30 seconds. On two wheels.

Meet the world's fastest ever road vehicle built to reach an astonishing top speed of 340mph.The Acabion GTBO uses jet fighter technology and aerodynamics to reach its extraordinary speed propelled by a state-of-the-art turbo-charged engine.Its designers revealed it could reach 300mph in a blistering 30 seconds - substantially quicker than the rival Bugatti Veyron which takes 55 seconds to reach its top speed of 250mph.Good grief, that would rattle your teeth!The article implies that an electric version is in the pipeline as well.Daily Mail story750 hp and 700 lbs vehicle weight result in more than 2100 hp per ton. They boost the jet-like GTBO to jet-fighter punch and to new dimensions of both efficiency and speed.V-max 340 mph at half throttle, governor limited.0 to 300 mph in less than 30 sec.Economic theories tell us, that you can not maximize effect and minimize effort at the same time. The Acabion GTBO proves the opposite. It minimizes weight and maximizes power and aerodynamic efficiency. The effects are just out of this world.100 mph at 1.7% throttle and 100 miles per gallon.150 mph at 4.3% throttle and 62 miles per gallon.250 mph at 17% throttle and 25 miles per gallon.Acabion websiteMore photos at Jalopnik

Topic by Kiteman    |  last reply

### Electric Bicycle Mod Using an 36 volt, 1000watt motor to make an electric bike. I have questions about rpm and torque. Answered

I have done some calculations, with wheels who have a 75inch circumference, i have calculated that 444 rpm should get me going about 40km/h or 25 mph. I don't believe that this is right. I am also wondering what amount of torque would be good enough for this situation? The motor is 1000watts, 36volts and 3000rpm. I am planning to use three 12 volt car batteries to power the motor. I would be using a chain and gear transmission system to reduce the rpm. I am looking to have a max speed of from 50 km/h or 31 mph to 40km/h or 25 mph. I would really apretiate anyones help with this, so i could then finish this project. thanks

Question by NoNameCola    |  last reply

### how can I make a dc motor spin with less rpm's to get started?

I took a DC motor from a electric mower and want to use it for a wind generator. But I need it to spin with less starting rpm's. How can I do this? I guess what I am trying to say is I need it to start moving in about 3-5 mph winds vs's 13-15 mph winds.

Question by swat420    |  last reply

### Flame-Throwing Wheelchair

With 15-foot flames and a top speed of 20 mph, this is a pretty serious piece of mobility assistance. OK, sure, it's a ridiculous device, but look at the flames! Link

Topic by fungus amungus    |  last reply

### Students Build Car that Gets 2752.3 MPG

Students at Cal Poly have made a car that gets 2752.3 mpg. It has three wheels and moves one person along at just 30 mph, but it can drive most of the way across the U.S. on one gallon of gas. "The 96 pound car has three wheels, a drag coefficient of 0.12, a top speed of 30 MPH, and a modified 3 horsepower Honda 50cc four-stroke engine. It originally clocked in at 861 MPG and has been continuously tweaked to achieve the mileage we see today." Link

Topic by fungus amungus    |  last reply

### can i build a 4' x 8' x 5'' expanded polystyrene coated with stucco?

It needs to be able to withstand 90 mph. it will be fastened between two posts

Question by narelmr

### what size dc electric motor would i need to make a motorcycle go over 100 mph?

180 pound rider and i dont know how much the bike weighs but it is a suzuki gs550e

Question by bornon511    |  last reply

### What is a good kite boarding kite size?

I would like to know how big of a kite I would need for kite boarding the winds are about 15-20 MPH and for a 120 lb person.

Question by squirt8500    |  last reply

### What is the "actual" impact velocities of two colliding objects? Answered

Is it relative to the observer, or one of the objects in the collision?  The reason I ask is that  Marilyn Vos Savant answered a question about this in her column and I think she did it an injustice by saying that: an object moving 50 MPH towards another object moving, say 40 MPH (in the exact opposite direction), that the force of the impact will be.....the same as if each had struck a stationary wall at each of those speeds.  I think she is assuming a "perspective" and not taking the relative postion of "observer" or participant into consideration making her answer, inaccurate depending on perspective.  (I've seen figures on the "relative" speed of a baseball leaving a bat) Any enlightenment on this would be appreciated.

Question by Goodhart    |  last reply

### Electric Motors?

Can a 3/4 HP electric motor ( from an old garage door opener ) have enough power to be put in a bike and get at least 10 MPH out of it. Also what batteries should i use, i think i have an 18v or 16v battery somewhere..

Topic by Katarukito    |  last reply

### can i build a 4' x 8' x 5'' sign from expanded polystyrene covered with a stucco coating?

It will be fastened between two posts. it needs to be able to withstand 90 mph wind load?

Question by narelmr    |  last reply

### Steampunk Gets Real

As reported on New Scientist today, the British steam-powered vehicle Inspiration broke the previous land-speed record for steam power, set back in 1906. The fastest of the two runs was 151 mph, set on a dry lake bed at Edwards Air Force Base.

Topic by kelseymh    |  last reply

### Swiss engineers build Bond-like underwater car

It is called the sQuba, and it is a car that runs on land, as well as in the water. Inspired by the Lotus Espirit, in the James Bond Movie, "The Spy Who Loved Me", the Swiss engineering company, Rinspeed Inc, was the mastermind behind it.If you are heading to the Geneva car show, it is expected to make a visit there.Read the full article at SFgate.com Company CEO Frank Rinderknecht, a self-professed Bond fan, said he has been waiting 30 years to recreate the car he saw Roger Moore use to drive off of a dock.The sQuba can plow through the water at a depth of 30 feet and has electrical motors to turn the underwater screw.You'll have to break out the wetsuit, however.The car has an open top, meaning that the two passengers are exposed to the elements."For safety reasons, we have built the vehicle as an open car so that the occupants can get out quickly in an emergency," said Rinderknecht, 52.Passengers will be able to keep breathing underwater through an integrated tank of compressed air similar to what is used in scuba diving.The sQuba's top speed on land is about 77 mph, but it slows down to 3 mph on the surface of the water, and 1.8 mph underwater.

Topic by Brennn10    |  last reply

### cheap powerful electric engine? Answered

Im looking to make an electric scooter for a school project, and im on a bit of a budget. I need to know what kind of motor i can get to move a scooter with a person and electronic weighing around 150 pounds on it, while still fast enough to go around 10 mph.

Question by thekasspell    |  last reply

### DIY Air-Powered Moped

This custom moped runs on compressed air to get you across town with no pollution and no noise. Just make sure you're not going too far as the range is only 7 miles and top speed is 18 mph.Still, a cool idea to work from. Link

Topic by fungus amungus    |  last reply

### British Land Speed Recod Was a Breeze, Thrashes US Record.

On the morning of March 26th, on the dry Lake Ivanpah, The Ecotricity Greenbird driven by British engineer, Richard Jenkins smashed the world land speed record for wind powered vehicles. The Greenbird clocked 126.1 mph (202.9 km/h) , eclipsing the old, American held, record of 116 mph , set by Bob Schumacher in the Iron Duck in March 1999 at the same location.The fully-composite craft (the only metal is in some of the bearings) used a solid wing to reach speeds up to five times that of the actual wind.The wing also provides unwanted lift, so it uses the same downthrust technology as F1 cars - at speed, the 600kg car presses down on the salt-flats with a force of almost 10,000N.Greenbird website.

Topic by Kiteman    |  last reply

### How to synchronize the brightness of a grille-mounted neon tube/LED bar to a car's tach/speedo?

I have a 1997 BMW 328i, and I've been thinking about installing either a neon tube or a bar of LED's in the grille of the car to use at night (most likely not street legal, I know). I want the brightness of the tube/bar to be controlled by one of two things: The speedometer or the tachometer. I.e., if the speedometer is at 0 MPH, the light is off, and if the speedo is at 75 MPH, the light is fully on. Same thing with the tach, light off at 0 RPM, light fully on at redline. Unfortunately, I haven't the slightest idea how to use the car's computer or the gauges themselves to set up a control module for the light. If any of you has a good amount of knowledge about automotive gauges, I would appreciate your help!

Question by Jonny Katana    |  last reply

### Jet Pack Speed Record Set

Over in Scotland, some crazy fellow has just set a new speed record for the jet pack at 61 mph. The official speed reading was done by some cops with speed guns apparently, although I'm sure the video evidence also helps. via Gizmodo

Topic by fungus amungus    |  last reply

### How can I apply a calculation to a frequency counter?

I am trying to find a way to convert frequency (as in cycles per second (literal cycles of a wheel)) into speed. I've found schematics and code for a frequency counter, but I want to be able to display the actual speed in MPH in LEDs. The calculation is simple enough to do - I just need to know if there is a way that I could covert the output of a frequency counter to MPH by way of some calculation, and if so, how.  essentially, I want to learn how to program, say, a PIC micro to read how often a reed switch is closed, then translate that into a readable speed on 7-segment leds. where should I start? what kind of chip should I use? Where do I learn to code? I am pretty much lost thanks for reading

Question by phephq    |  last reply

### Can anyone help me with a NASCAR 09 car setup? Answered

Hi daredevil499 here, so I was wondering if anyone knew of a great car setup for Daytona international speedway on NASCAR 09 for the playstation2. I want a setup that will make me go 195 mph or faster please. Don't worry if you can't. Thanks

Question by daredevil499

### Forza Motorsport 2 Mods! (UNCOMMON MOD HERE!)

Post all your Forza Motorsport 2 mods here! How to do my mod is a secret. Some of my car's specs: HP: 623,529 Torque: 614,934 ft-lbs Top Speed: 435453 MPH Downforce: 3455 lbs Boost Pressure: 432.87 PSI

Topic by Tom1795xx

### Homemade Jet Truck with 2700 HP

Jets keep getting added on to other items. Just a few days ago it was a bike and now it's a truck. This combination weighs in at 6,600 pounds with 2 occupants and still takes 8.5 seconds to hit 60 mph, but just think of the looks on other drivers' faces when you fire it up on the highway. Jet Truck

Topic by fungus amungus

### Amazing Human-Powered Vehicles

Hey everyone, I'm part of a team building a bike for to break the human-powered land speed record of 83 mph!  Check out our kickstarter page at http://kck.st/1o5DowU, or our website/blog www.aerovelo, for updates on the design/construction/testing process. We've worked on a few other crazy human-powered projects including a helicopter and an ornithopter. Check it out! :)

Topic by aerovelo

### How big a propeller would I need to turn a 3500 watt AC gererator?

A friend of mine gave me a 3500 watt gasoline AC generator because he burnt the engine and he did not want to fix it due to cost. I want to use a propeller instead of a gas engine to make it operational. Is this practical? The wind here blows constantly between 20 and 30 mph.

Question by dukexyz    |  last reply

### HOW DO I DETERMINE HOW FAST AN AMOUNT OF HORSE POWER IS?

Hey guys i was interested in making a go kart but i dont know how fast my 6 horse power engine will go. How do i determine how fast 6hp is, infact how do i determine how fast any amount of horse power is. p.s. : i dont care if it is in mph or kl/h.

Topic by rickick    |  last reply

### Power (Torque x Rpm) need to move 100kg car to 1.86 MPH/3 KMH in about 3 seconds?

I am planning to build the electric car. But having no experience in physics. My Electric car have following specification: -> 4 Wheel Car -> 100Kg car weight including Person weight -> Wheel size can be 4-8 inch I want to move the car on flat road (No incline) to about 3-4KMH / 1.86-2.48MPH in about 3-5 seconds. I want to know that how much power it needs to attain that speed. Also I want to know that how much power it needs to overcome rolling friction in order to move the car. I have the dc motor of 2kg.cm or 0.2N.M torque and 7k rpm, can I use this motor to attain that speed. Also please can someone tell me the formula according to my specification so I will alter the wheel size value to calculate the power needed to attain that speed. Also is the torque of 2kg.cm or 0.2N.M and 7k rpm is enough to move the car or I have to setup the gearing? If have to setup the gearing then can you please tell me the ratio. Thank  You!

Question by wahabfun22    |  last reply

### could I turn one of those old barbie cars for kids that only go 5 mph into a mini offroad beast? Answered

Do you remember those old barbie cars for kids that only go about 5 mph, a barbie radio, pedals for brakes and going forward. Those old things. I am not good with motars engines elctronics thta stuff i am more of a machanicle(i know thats misspelled) builder so I am no good at that type of thing. But I was wondering if someone could tell me how to turn the barbie car into a mini off-raod beast and the parts I need to do it. Im not going to make an ible' on it since it would suck so anyone can use the idea. I want it to go about 10mph+. Try to keep it low price too. I dont have the car right now cause if i got one and no one commented then it would be a waste. So can someone help me?

Question by ostomesto    |  last reply

### Robot baseball thrower

I am 13 year old and really like baseball. My dad used to pitch to me so i could practice and get better. but he threw out his shoulder and can no longer pitch. i do not know much about robotics and just want something to pitch to me. What i need it to at least do is... throw 65 mph stand on its own and be pretty accurate please help me!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Topic by yoda-iz-my-idol    |  last reply

### How do we remember? Answered

If anything was an inspiration to education in the wider sense I would think the breadth if not the depth of knowledge the regular answerers here show is an excellent example. How much information can the human brain contain without exploding. Where in 1972 was a speed record of 11.2 MPH set? Who was the second president of the USA Alphabetically what are the first and last US states. What was the Beatles first film We can all, (well mostly), look up the answers but knows of the top of their head??

Question by rickharris    |  last reply

### Man Crashes SUV Through Local Building.

This is huge news, a man crashed into a building right in the middle of town at over 75 mph. It is probably hard to understand it's importance if you are unfamiliar to Gig Harbor, but I've walked past that building and driven down that road thousands of times. The building used to be a restaurant, but the owners sold it and it became a fitness gym. It's right at the heart of Gig Harbor, basically. GIG HARBOR, Wash. - An SUV crashed into the 1-2-3 Fit gym at Pioneer Way and Harborview Drive early Wednesday, killing the driver.Witnesses said the driver was traveling at about 75 mph when the vehicle crashed into the building at about 6:30 a.m.The SUV came to rest on a desk.The 26-year-old driver, who was not wearing a seat belt, was killed instantly.Four or five people on exercise equipment narrowly escaped injury. Gym member Ryan Ryan was doing push-ups at the time of the crash."The odd part about this is there was no attempt to miss the building, no attempt to brake, and the vehicle speed was three-four times the speed limit," said Ed Troyer of the Pierce County Sheriff's Dept.Link and Video.I know it's a few days old. I was unable to post a topic earlier because of homework.

Topic by Spl1nt3rC3ll    |  last reply

### Remote Control Need Info On How To Build It? Answered

I what to start a project to build a fast and strong remote control small car about 1.5ft with - 2 ft length - 1ft in height at highest point going down to at about a 20 degree angle. and on that a flipper going across the 1.5ft with. I wood like it to travel at up woods of 20 mph and very agile with two weals and a couple of casters at the front. I need help on what to get and were to get them from.  Thanks if you can help.

Question by 95styles    |  last reply

### Bicycle accident is the frame okay? Answered

I struck basically struck a curb (an unmarked road island really) going 17 mph roughly and blew out my front rim. I broke a collar bone because of the accident. Anyways I was wondering if the frame is okay I looked at it and there was no visible cracks anywhere. Its a cheap Schwinn frame and it got me wondering if it would be safe to put a new rim on and go. BTW this is a gas powered motorized bicycle not the cheap ones as shown BEFORE the crash.

Question by Ghost Wolf    |  last reply

### where can I get a pair of electric motors capable of moving about 40kgs each for under ÃÂ£60? (from the uk) Answered

I'm planning on building a small personal tracked vehicle for myself, and because of how I want to do the steering and various other things I want to use an electric motor on each track. I don't have a huge budget (I'm 15), which explains the price, but I would like this to do at least 2 MPH. Can anyone help?

Question by scarabeetle101    |  last reply

### Are there any legal suggestions for getting people to slow down on our street?

I'm talking guerrilla warfare. We don't have sidewalks and narrow country roads so walking with a stroller or a dog means you risk life and limb to leave the house--no one drives the 25 MPH speed limit (except me). The town police and the town traffic commission are useless and totally closed minded to any traffic calming suggestions, especially those that cost money. I just want them all to slow down. Any suggestions??

Question by TeaQueen    |  last reply

### Legality of home-built electric bike?

I live in northern New Jersey. My summer project is to build an electric bike/motorcycle. I plan on using a regular beach cruiser pedal bike, removing the pedals and mechanism, and powering it with an electric motor. I'm estimating it will go anywhere from 20-25 mph. I know the laws about mopeds and motorcycles, but what would this fall under, since it will be custom and home built? I'm using Radioactive_Legos' Flat Tracker as a reference https://www.instructables.com/id/48V-Electric-Flat-Tracker/

Question by AudioMaximus    |  last reply

### speed vs. distance?

Hello All, I am considering building a electric motorcycle in the next year, all the Instructables I have read on the subject boast top speeds of 70 mph and a 10 - 20 mile range. I live in a small city in Canada where the maximum speed limit is 50KMh(~30mph) and the city is not even 7 miles across, also there is nothing outside the city that is close enough to get to with a ev such as this. My question is how does the speed and distance connect, for example, if I was to travel at half the speed would I be able to expect to get double the distance?

Topic by alexm    |  last reply