The case for motorcycles. Why not use one?
 

As of this writing 6 of the top ten on this site are motorcycles or scooters. It's no surprise that these are very efficient forms of basic transportation, witness thier widespread use in developing countries where fuel is a large expense.

For most commuting requirements they fit the bill very nicely. They are reliable, cheap to buy, cheap to own, easy to fix and augment owning a vehicle with carrying capacity well.

So a question to the forum participants: Who ISN'T using one that would like to, and what's keeping you from buying one?

Well, in many countries, the fuel culture is very different.

First, there are places that have incredible taxes added to the price of gasoline. Europe is a great example.

Next, using Europe as another example, vehicle taxes are huge. So, if you'd like something like a 3.0l V6 VW, you're gonna spend thousands extra for the purchase in addition to thousands extra every year over the cost of registering a car with a smaller displacement. I know that limit used to be around 1.6 to 1.8l engines. That's why there were so many smaller engined cars coming from Europe that had good mileage that the US didn't have.

More, storage is a premium. So, keeping a larger car in a city that's been existance for 1000 years can be hard. You just don't have the available garage space, or road space.

So, a motorcycle fits in a small area, uses less gas, and it doesn't cost as much to own. With taxation very high, affordability is important.

So, the culture has had motorcycles as a regular part of the "road scape" for a long, long time.

Here, well, I don't think people pay attention very well. I have raced motorcycles for over twenty years now, and, frankly, it's scary out there on the road with the cars and blue haired ladies turning left in front of you.

yes, I would lover to travel through Yellowstone by bike, but I still prefer an air conditioned ride getting there with the family.

Occasionally, I do get a yearning for a street ride. More for the tinkering aspect and the unique opportunities that one do with relatively inexpensively with motorcycles of all brands.

My current bikes, race only: SV1000S and a GSXR750. I have an old H1 in the works, but that's an on going project.

Safety. I think I'd kill myself inside a week, haha..... plus in the winter time, a motorcycle is out of the question, here in Colorado.

uhm, mostly because it won't tow my trailer and equipment.

As for the cars, I hardly put 5,000 miles a year on them both, then I'd rather drive less still before I get on a bike, if it came to that.

Because I'd rather get crappy mileage but great economy, then there's the safety factor.

LOL!

https://borealphotography.com/forum/5.jpg

Too many idiots on the road here to get a bike. I mean, I'd LOVE one. 50-60mpg driving to work would cut my expenses enough for the bike to actually pay for itself, but I can't bring myself to buy one with the way people drive here in New Mexico.

Most people will respect a motorcyclist, but there are always a few idiots that either don't pay attention or claim "I didn't see you". Always ride with an escape plan - plan on them NOT seeing you.

Riding a 2 wheel vehicle is higher risk and you are more exposed - to the weather and bodily harm. Icy or packed snow on roads can be very tricky.

Storage or hauling is limited. But you can get creative with tank bags and saddlebags. Or using lots of bungee straps.

Most motorcycles are much dirtier than a modern car in respect to emissions. A few have catalytic converters (mainly newer models).

Fuel mileage can be great with a small to medium sized bike that is ridden with economy in mind ( resist the calling to blast thru the gears!)

Years ago I would ride year round. Now I'm a wimp - when the temps get below 50 deg F, I stop riding.

Check out what's been happening in the Midwest over the past week. I'd be up a creek. In fact, many of the shop guys razz me up for not having a truck in this weather!

License is the only reason I don’t have one. If it was as easy to get a license here in Japan as it was in the states, I would have had a license 2 years ago. Unfortunately, there are a lot of problems with getting one, and the BS bureaucracy here. I will try for one next year just to see how bad it really is, and I don’t want to waste all of the work I have done to make the pencil pushers happy with my paperwork. Plus it will be great information for those who come after me who want to get their motorcycle license in my program. We have accumulated a lot of car information, but the bike information is completely lacking.

Next, the safety thing isn’t as big a deal here. There are enough scooters everywhere that most people know what to look for. But, I ride like everyone in a cage is a blind deaf idiot hell-bent on killing me, so it won’t really matter as much. Plus, it would be nice to have two vehicles, that have less displacement then one of my father’s truck cylinders.

I'm just broke and way to scared off the michigan winter. A ninja 250 would be amazing though

Likewise. So far, I've personally witnessed two accidents - one high speed on the highway. Watched a truck merge into the guy (this truck was going a lot faster and weaving through traffic) :/

My TA for a class I took this past semester go in a pretty bad accident - someone in a silver honda something or other merged into him on his way to teach our lab! It was a hit and run too :thumbdown: :thumbdown:

beatr911 -

I used to have a motorcycle and I tried to use it to save mileage on my car. It was great for easy FREE parking at UCLA and I could squeeze between the bad traffic when needed.

I consider the danger factor to be the "price of convenience".

But besides the danger, there was the overall wear and tear on my body. The act of riding my motorcycle in LA traffic wore me down. For my 30+ mile round trip commute, I was dog tired at the end of each leg. Too much stress.

CarloSW2

I've been riding on the street for 27 years almost continuously. I don't ride when it gets below freezing in the mornings which is about 3 months out of the year. As for safety, everyone has thier threshold and thier own ability to manage the risks of riding. I takes focused attention during the ride to stay alive, and that is part of the appeal to me. It takes my mind off of work, family stress, etc. for a while.

I tell my wife it's a matter of when, not if, I get into an accident. Fortunately my life has been fairly accident free in all respects. I continue to learn safe riding methods and do everything I can to keep it safe. I just love riding and hope others can share the enjoyment.

I've strongly discouraged friends that wanted to ride, solely because something always seems to happen to them. On a bike it obviously can be very serious. It's better off that they are in a cage (car). If you have a fairly accident free life you may be fine on a bike. Everyone rider should take a motorcycle safety course every 10 years or so to keep the knife sharp.

I rode for about 15 years. The first was a CB1100F and the second an ElectraGlide. I don't remember what mileage the fastbike got, but the best I ever made in the Harley was about 45mpg. I usually got around 41-42. I can get that, and better, and have four tires, a windshield, a stereo, A/C, and a cup holder.

My biggest fear was having a catastrophic failure while surrounded by bigtrucks. Leaving this world as roadkill is not on my list of things to do. You've got be sharper than the average bear to stay untouched on a bike.

I'm getting older, and am lucky to still be upright and mobile after the things I've done. My Tempting Fate account can't have much in it any more, so I gave up on two-wheelers. It's scary enough driving a CRX in fast, heavy traffic.

Got one a couple months ago. Mostly it was the parental units (*ahemMOMahem*) who kept me from getting one, but she's reluctantly backed down since my Dad and I got our M licenses together. Gotta love 50mpg, but my hands get too cold too easily and the season's turning to the cold and soggy one...I ride whenever I can, though.

It could be useful for the city. In Australia, you can buy the used postie bikes (Honda CT110) that get 1l/100km highway, which indicates that when driven with FE in mind they can probably do better than that in a combined cycle.

https://img88.imageshack.us/img88/4442/bikelgelk0.th.gif

From what I've seen of motorcycle fairings, I'm not very impressed with their attempts at drag reduction. Consider how large an area the wheels are wrt the whole frontal area. Compare that to a car, where the wheels account for about 20%. I would not be surprised if they account for 50% of the drag.

I'd fair most of the front of the wheel like an aircraft wheel pant, and attempt to do the rear. After that a bubble for the front. In my drawing I should have made the top of the wind shield closer to horizontal, oh well.

[IMG]https://img149.imageshack.us/img149/6...ndlycm2.th.gif[/IMG]

Revised:
https://img509.imageshack.us/img509/4507/bikedo5.th.jpg

The point of that is a good reduction in drag coefficient, while keeping the addition to the side area increase to a minimum (to reduce buffeting from crosswinds). Note that the wheel fairings will hardly hurt in sidewinds because spokes have a huge drag coefficient anyway, a flat plate would hardly be any worse. You could also stretch lycra from the front and low part of the fairing to the back, streamlining a large portion of the frontal area without increasing the side area.

Of course, the other option would be to go the whole hog with basically a modified HPV design, see here. Better drag coefficient from the front, at the expense of more buffeting from the crosswinds.

https://img156.imageshack.us/img156/2...al99pc0.th.jpg

With a 105cc motor the fuel used in the glide portion of a pulse and glide would be negligible. But I'm not sure if you'd achieve a better CdA than the vw 1 litre car with those modifications.

I leave my motorcycle in the garage when rain is threatening or its under 50.

There are safer modes of transportation and I think this scares many people away from bikes. I have had cars pull out directly in front of me twice- but managed to find an escape route both times.

I sold my 650 Honda after I snapped my ACL in an embarrassing 5mph accident (all my fault- no other vehicles involved).

When I was in college, I recall seeing a guy on an old BMW boxer go down on an icy road. He just skidded to a stop, picked it up and drove on- just a little slower than before- he had more guts than I do.

When I lived in California motorcycles were my main (nearly exclusive) mode of transportation for about 20 years. For several years my commute was 80 miles per day, always by motorcycle, rain or shine. Now that I live in Bend Oregon the snow and ice keeps me in the car for nearly half the year, but the car I have now gets better mileage than my trusty CX500 motorcycle. I now have a 200cc motorcycle that gets better mileage than the car so it'll be the choice for next summer.

Q

Agreed. Motorcycle fairings are about styling primarily, and then some amount of buffeting as a secondary concern. Recently, yeah, there has been a bit more attention as there hasn't been many huge strides in MC engines for a while. They are making them more powerful with more rev's, but ti valves can cause problems over the longevity of the bike.

Crosswinds are pretty rough on bikes. In road racing they were outlawed from the international bodies in the 50's/60's as they led to some deaths on track. Yes, they did allow better acceleration and higher top speeds for those that worked on such designs, but they never really moved much into the main stream production market.

Over the years I put about 70k miles on motorcycles but where I live now I am just afraid of the cars. I take risks. I just chose different ones.

My wife and I road down to the store a while back on bicycles and the next week a woman on some medication had some sort of problem and ran over a bicyclist with her SUV. Same road we had been on. It does make one stop and think a bit.

True that you could get superb FE on a bike.
But this Volvo driver here wouldn't travel that way.
Just too scary for me. I like that nice steel cage around me.
It helps keep you warm in the winter, too.

I'd seriously consider a Civic HX for my next car. But I think that's as far as I'd go towards lighter weight and less protection. One really nasty accident can ruin your whole day.

I rode to work yesterday :)

So far I have rode in 28 degrees F and 35F with freezing rain. I guess a dualsport is far more flexible and forgiving in bad weather than a cruiser or sport bike.

If you are worried about safety here is the gear I ride with

Olympia AST jacket
Olympia Airglide 2 pants
Cortech Scarab gloves
Acerbis X-tight boots
Dayton Modular helmet

That combo is good from ~25F to 100F I just swap from those cortech gloves to Alpinestars Alloy gloves when it gets warm.

What exactly was outlawed in the 50s/60s? You omitted to say, and I'm curious as to what was outlawed.

Note the hayabusa has a token attempt at a front fairing for the wheel, and that has the best CdA of any of Suzuki's sport bikes.

https://img267.imageshack.us/img267/7...5459ig1.th.jpg

The drag coefficient of the hayabusa is 0.56, or about half that of a barn door.

Due to the high performance engines that most motorcycles have (anything over 600cc) and their poor aerodynamics, motorcycles do not get that great mileage. A 600cc would probably be around 45mpg and an 1100 would probably be lucky to get 40. A smaller twin cylinder might get you in the 60mpg range but are pretty underpowered at freeway speeds. As funny as it sounds, you can escape some bad situations in traffic by just blasting past it and you couldn't do this on a 250.

The other consideration is tires. A sportbike can go through a rear tire in less then 8000 miles (and much less if you ride aggresively) A rear tire for a sportbike can cost over $200 and $50 to mount it. Fronts last longer, but they aren't cheap either. And on a motorcycle, it is not a good idea to buy cheap tires or run them down on the tread, good traction will save your life. Touring tires last longer (maybe closer to 20000 miles), but they still don't last as long as tires do on a car.

Overall, if you ae getting one to save money, I think you would have a hard time getting a motorcycle to save you alot on long commutes when compared to a small, FE car.

Is avoiding freeways an option? Plus almost every motorcycle I've seen zips to the front of the lights everytime it is backed up at a red. Then you wouldn't need acceleration at 100kph to save you.

The other advantage is that your combined weight on something like a postie bike is about 200kg or less. My car is about as light as cars get, 760kg for car + driver. If my car was a hybrid, ignoring weight of batteries, they'd need to have > about 75% efficiency with regeneration to be better than the bike. I believe the prius's regenerative braking system is about 30%, someone correct me here.

So you've automatically got more tolerance for more frequent stop/starts.

So, bikes have a tiny engine, which means great idle efficiency for glides. They have a tiny frontal area. With fairings, the drag coefficient can really be cut down, in fact, an hpv like bike can do better than a car because there is no ground effect on most of the vehicle. Rolling resistance is minimal because of low weight. Stop start losses are minimal because of low weight. Acceleration is great because of low weight.

Flintstones foot start for the win.

Thanks for the link! It's amazing what you can find once you know the correct search terms.

As this link posits, I believe the crosswind argument is a pretext for banning, but not a reason. It is not some magical property of low Cd fairings that causes large force in a crosswind, it is simply area normal to incident airflow multiplied by the drag coefficient at the angle concerned. The drag coefficient from the side could not get any worse than it already is. A fairing can increase that particular area, but it does not have to. My modified postie bike would have maybe an increase of 10-20%, if that, which is neglible (I don't count the wheels because spokes would be as bad as a flat pannel, possibly worse.)
Something like the postie bike is engineered for fuel economy. Australia Post has no interest in their employees looking mean or doing wheelies. It's cheap for Honda to just modify their Cub for that purpose.

Again, there is no real reason why that has to be the case. My car coasts very well at 760kg. The drag coefficient is about 0.26.

I don't see why a well modified bike couldn't get near that drag coefficient, and with maybe a third or less frontal area, it would coast almost as well. It would coast great at 80kph or less, which is where you are spending most of your time in the city anyway.

Anyway, thanks for the response! It's amazing how engineers of the past got things mostly right back in the beginning, before Alfred Sloan created the transportainment industry.

I think it's a cost issue with smaller bikes. You've got the actual fairing, then all the mounting bracketry. Mounting a simple fairing/windshield to the handle bars, a cheap, easy way to do it, rather than to the frame at the steering head also transmits any wind buffeting into the steering of the motorcycle.

Adding a fairing also adds weight.

Really, without a fairing, there's not a lot of frontal area on a bike. It's not smooth, but it's very small. I've seen race team test where they have gotten rid of the production full fairings and produced higher top speeds. Again, these aren't "dustbin" fairings to start with.

I think bikes now are designed heavily towards performance rather than anything else such as FE. I don't really blame the designers/builders; it seems that's what the "market" wants, at least in the U.S.

To remedy that on any given bike - - -
There was a thread re. someone considering or recommending regearing the bike by changing the chain sprockets. I'd think you could drop the rpm's considerably this way, without changing anything else. Might need a correction to the speedo/odo depending on where the sensor is.

A lot of bikes have the speedo pick up coming off the countershaft sprocket. So, yeah, you'd need a "Speedohealer" to correct it after making changes to the overall gearing. The gearing changes are relatively easy to do.

They are becoming more efficient. More electronics on the ECU, fuel injection is common, but not as sophisitated as on cars, Cats on a lot of bikes.

Still, getting 45MPG on a machine that produces 0-60 times in less than three seconds with quarter mile times less than eleven with a cost of less than $10k. That's your common 600cc sport bike.

A bike's best defense is performance often. When I did street ride, it was important to me to make sure that I was going a little faster than traffic as I could manage better what I was coming upon rather than those that were over taking me, read as attempting to run me over...LOL!

The larger portions of the motorcycle market is cruisers. Standard and "metric"...read Harley-Davidson and the Japanese and other manufacturers. Basically large displacement twins from 1000 t0 1500cc's. There are larger displacement models too, up to 2000cc from Kawasaki, if I remember correctly.

But those aren't bikes that people are buying for economy either.

I think you misunderstand me. The postie bike is made especially for Australia Post, but is similar to the cheap bikes produced for the Asian market. I'm not saying it would be cheap to fair it. I was saying that it was cheap for Honda to make for the Australian market as is, unfaired.

Although, it wouldn't cost them much, they just don't perceive any demand (and there won't be, until enough consumers are educated).

I'd equate it to specific market segments.

I had to look up a Postie.. . :D I almost got one of those about fifteen years ago used. In a lot of ways, I wish I did...

Anyway, a manufacture has several models in a line up. Honda already offers small displacement bikes with full fairings like the CBR125.
https://www.highpeakmotorcycles.co.uk...3_DCP00590.jpg
Would probably be hard to justify making an aero version of an existing utility bike. Might be more economical for an aftermarket company to develop, manufacturer, and market such an item.

That would be my take from my work inside the MC industry.

In all of the motorcycles that I've seen in working at a friends motorcycle shop, I've never seen the speedo pickup coming off the countershaft, it alwas connects to the front wheel hub, you can even get induction pickups for digital speedometers that simply count the speed of the passing gear teeth without any mecanical connection.

I really like having a motorcycle in the summer, they are easyer to park, use less gas, are cheaper to regester, and in the case of mine, it's over 20 years old so I have collector plates that will never expire.
Last time I did a cost per mile comparison, my motorcycle was less then 11 cents per mile, and my car was over 25 cents per mile to operate.

We gotta get you into some newer production stuff...LOL!

It's pretty simple. A little rotor gets placed on the end of the counter shaft outside the front sprocket, and there's a pick up on the front sprocket cover. It's electronic, not cable driven. Every production bike that I've had since 1998 has had that style. I didn't race my own bikes for a few years, so I can't tell you when the transition was, but anything produced more recently has it.

With fuel injected bikes, speed is part of the ECM. Some bikes are even fly by wire in that the throttle does not connect to the FI butterflies at all. That's all controlled by the ECM. Basically, it's the furthering of traction control in bikes. In the late 80's GSXR1100's had a different ignition map for first gear to keep people from looping out. In fuel injected bikes, each gear, generally, has a different map.

I would think something like this would get very good mileage. Somewhat aerodynamic, small displacement, single cylinder, sport bike. Cheap too, about $1300.
https://www.fuelly.com/attachments/fo...5681c2ae0e.jpg

Q

I'm not saying the dustbin (as in the Cx) is the best way to design a fairing. As you can see from my designs, the center of pressure would be hardly moved. Although most likely not necessary, you could fair a bit more of the back to make up.

I strongly suspect that there are three main things you can do on a motorcycle to reduce drag.

1. Enclose wheels, because these get air rotating around with them, effectively having much larger area than they do. This couldn't get worse than with a bike, where the wheels are totally exposed (but don't have to be).

2. Smooth the airflow at the front, like a bullet. This gets the air flowing to the maximal area with as little resistance as possible. After this there is a wake, which you can either hide stuff in (like a rider and the rest of the motorcycle), or eliminate via a smooth, gradual taper.

3. Reduce the pressure drag at the back via said taper.

A dustbin fairing has no substantial taper back, and contributes a reasonable amount of side area. I suspect that 90% of the job it does could be done by fairing the front wheel and the handlebar to top of driver region, in something with relatively small side area.

Well, let have a look, shall we? Figures of around 0.56 square metres are bandied around for the hayabusa. So lets say that a more upright bike like the Honda CT110 has something like a frontal area of 0.8m^2. My Mira has a frontal area of 1.79m^2, and that is very small for a car. Which is less than half of mine. Something in a sport bike or recumbent style would be in fact less than 1/3.

Now, the initial drag coefficient is close to 1. A flat plate would be just as bad. I suspect that properly fairing the wheels and doing what I did in my Gimped version of the postie bike, you'd get it down to at least 0.5. At that stage, the CdA would be a bit less than my car. Maybe more, because not many people understand why unenclosed, rolling wheels are so bad for drag.

Going further, what you describe as radically faired need not be impractical. It's more a matter of fashion. And fashion is fickle - back a few hundred years ago the height of fashion was the codpiece. What "people won't do" is not constant.

The practical HPV I linked to earlier seems to indeed be practical.

So quantifiably, coast time is proportional to m/CdA.v^2.

Ignoring velocity, my m/CdA = 765/.46=1675 kg/m^2

Typical postie bike = 200/(.9* .8) = 277 kg/m^2, so coast time would be 16% of my car.

Modified with front shield and wheel fairings, I'm estimating 0.5 for Cd. So m/CdA = 500, or 30% of my coast down time.

I'm estimating 0.2 for the Cd of a practical HPV style modified postie bike.
m/CdA = 200/.8/.2 = 1250, or 75% the length of my coasts. Which is close enough not to worry about. Recumbent or sport bike style would probably beat my coast down times. Remember that there are many people here who are P&Ging with m/CdA worse than my car.

The other thing to consider is velocity. A 10 kph coast down in my car is about 8.5 seconds at 100kph. I happily do that. The modified postie bike would have a 10kph coastdown time of 8.5 seconds at about 55kph. I do a lot of my driving at 60kph or less, so this would certainly be worthwhile doing from my perspective.

I haven't ridden a motorcycle in a long time, but do they have a similar mechanism to a regular bike, where it automatically coasts if you do not provide peddle power? Is it easy to do?
You are right, thanks for making me double check my figures, although I don't believe it is an insurmountable problem.
Actually you'd be surprised. Remember that the force of rolling resistance is proportional to mass. Since mass is at LEAST a 1/4 of that of a normal car, drag takes over at a much smaller velocity. My calculations have it at about 18kph for the unmodified postie bike. That's tiny!

https://www.freedomsphoenix.com/Uploa...dian-cycle.jpg

Mr Munro's set up.

It won't automatically coast. A regular motorcycle has a gear box. Not like a car where one can put it into neutral from any gear, but current production bikes have neutral between first and second gear.

What are you assuming for a weight? My 600cc production race bikes weighed about 378 to 388 pounds after a race, depending upon how much fuel I wanted to have in the tank, still not being empty with the smaller number. Yes, there are heavier bikes, but production practices have continued to yield lighter bikes. I'm not sure what one would call average, but the Postie dry weight, no gas & no oil, is about 200#.

That's exactly what I figured. I'm using 100kg for rider and gear, being near enough to 200kg for rider + gear + bike as a round figure.

I think that besides obvious resons such as ssfety and protection from the elements, there are other reasons why more people don't ride motorcycles.

1. Price/Value - Okay, so a motorcycle is going to be cheaper than MANY new cars. But this is not always the case with ANY motorcycle vs ANY car. This is particularly the case if we are considering the cheap end of the used market. You can find a decent running used car for MUCH less money than a running motorcycle. Also, at ANY level, you obviously get more for your money from a car.

2. Ability to carry stuff. This is another obvious one that maybe many might not think of. Anyone ever try to go on a $100 grocery shopping trip on a motorcycle? For that matter, how does one go shopping if a motorcycle is all they have?

3. Carrying passengers. This is, of course directly related to the last problem. You just can't carry a family on a motorcycle.

4. Theft. Not many people think of this one. But I know several people who have lost their bikes. All it takes is for three or our motivated guys to drive aroud in a pickup.

For all of these reasons, as well as ones mentioned above, motorcycles are just not practical as a primary vehicle for most people.