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Railroad Bicycle

Railroad Bicycle

Railroad Bicycle

(OP)
Hey guys,
Im contemplating making a railroad bike.
What I've found on the net, looks pretty terrible.

My thoughts are to make a bike that performs better than my high end road bike, mainly though lowering the rolling resistance, since I'd eliminate the tires, and rolling on a extremly hard and smooth surface.

What I have seen online used an out rigger and guides to hold the front wheel steady, which almost negates any advantages.


So I found the cross section of a rail road rail, along with some specs:


and the heads vary between 2-1/4" to 2-3/4" in width


So I'm thinking why cant I just make a rim that is either V shaped or simply curved, and it will sit on the rail and self align?
Thus I will have minimal contact points, and lowest rolling resistance? and thats it?


Also should this work, what kind of increase in speed?decrease in resistance or energy output might, I expect to see?

I'm working on it!

RE: Railroad Bicycle

I'm not expert in bicycle design, but I seem to recall that this concept can not work: to maintain the equilibrium the cyclist needs a handlebar and uses it with very small corrections even when going on a straight path, especially at low speed.
I would try with a simplified prototype on a real track before going on with a research on optimization.

prex
http://www.xcalcs.com : Online engineering calculations
http://www.megamag.it : Magnetic brakes and launchers for fun rides
http://www.levitans.com : Air bearing pads

RE: Railroad Bicycle

you wouldn't need handlebars if you're going to ride both rails of the railway.
the slope (both rails are canted towards each other at a 1:20 or similar angle) makes it self-centering (if you have a symmetrical loading).

I wouldn't reinvent the wheel (literally), I'd take a good look at railway cars and copy that design (maybe a tad lighter, though).

If you're going the make a bike that rides only one rail, good luck with that, I'd be interesting in seeing your prototype(s)...

RE: Railroad Bicycle

Rail looks like that off the roller.

Not after it's been used for a while.

RE: Railroad Bicycle

In Europe, rails are mounted on concrete ties with such a slope cast in.
No matter the vertical loss of material due to wear, the slope remains.
Hence, self centering effect stays.

The flanges on the wheels also keep the trains on the track, so even if you're dealing with extremely worn rails, the cars won't derail.

We regularly use railroad for transport, I can easily provide pictures.

I wonder how the railroads your side of the world look like ???
The self-centering effect is on of the basics (almost) the entire railroad system is based on...

RE: Railroad Bicycle

Quote:

I'm not expert in bicycle design, but I seem to recall that this concept can not work: to maintain the equilibrium the cyclist needs a handlebar and uses it with very small corrections even when going on a straight path, especially at low speed.
This. I recall hearing somebody took a bicycle and welded the front fork in the straight position, to test this theory. The bicycle couldn't be ridden, it would fall over.
I suspect this is why you have to "learn" to ride a bicycle. Unconsciously, you learn to make small movements in the handlebars to let you keep your balance.

rp

RE: Railroad Bicycle

The riders body weight shifts over to each side every stroke of the pedal so yes, without movement in the forks or a stabiliser it would be very hard to do or inefficient.

I have seen a bike with a stabiliser running on the other track. The forks were not welded in position either, they had a guide running out the front with 2 wheels mounted horizontally either side of the rail much like a roller coaster does, to keep it running true.

Running on one track would be possible but the stresses on the support mechanism would be huge and it would need to be made from thick metal and become heavy.

RE: Railroad Bicycle

Eliminating rolling resistance from tires, also eliminates traction available for accel/decel. Toss that one in the "con" column as well.

RE: Railroad Bicycle

Do you suppose that the lack of rolling resistance is the reason for the application of sand to increase traction for rail wheels?
It seems like what may be gained with less rolling resistance will be lost in the self-aligning or flange friction.
If an outrigger is used, some means of allowing for varying track width must be provided.

Ted

RE: Railroad Bicycle

I work in an very closely related field (although I've only been at it a couple months), and also have a cycling background.

Some considerations:
1) First and foremost, where will you ride it? Railroads don't take kindly to trespassing on their right-of-ways. Hard to go on a 60 mile rail-ride without access to at least 30 miles of rails.
2) Many railroads (particularly metros) run special profile wheels and rails. It's not a uniform standard.
3) Railwheels only have one flange, on the inboard side of the wheel. If you design something that has two flanges (one on each side), you won't be able to ride across at-grade street crossings, switches, frogs, etc.
4) By going to a steel wheel, you may reduce rolling resistance but you are likely adding weight, and in the worst possible type: rotational weight. Something with the strength, hardness, and cross section capable of cupping a rail is going to several times the weight of a nice road bike wheel.
5) Lots of rails are "jointed" every 30 feet or so. You've got a joint bar bolting two sections together, and they may or may not be well aligned (particularly if you've managed to find abandoned rail that is no longer maintained). With no form of suspension on the bike (not even a tire), you will feel every joint shaking you to your bones. You could add some suspension to make it tolerable, at the cost of weight and energy loss (which you are seeking to minimize).

I think it's a pretty terrible idea, but if you are committed you may want to look up information on railroad "speeders" which are tiny transport cars that people restore and take on rallys. Might be a decent source for wheels and whatnot.

RE: Railroad Bicycle

You might want to consider what your proposed wheel will do when it encounters a switch point.

RE: Railroad Bicycle

I don't have it now, but starting at the TRS I think, I found a paper that outlined how the rail/wheel interface works. At least in the US, the rails are crowned, as in the drawing above, and not intentionally tilted to my knowledge. ... but the visually cylindrical parts of the wheels are actually tapered. So the interaction of a pair of tapered wheels with a pair of crowned rails tends to center the vehicle between the rails, without the flanges getting involved.

Mike Halloran
Pembroke Pines, FL, USA

RE: Railroad Bicycle

(OP)
well part of what i wanted is to be able to simply pick the pick up and easily carry it around any obstacles, and additionally, possibbly carry a set of normal wheels/tires (on a rack) so that I could ride "around".

I did contemplate using possibly a thin rubber coating for traction, but all those things wont matter if they basic idea doesnt work.



I have been contemplating the whole balance issue.
and I did think about the micro adjustments a rider makes.
and I could see how at slow speeds it could be difficult, But if you could conquer that, and get up to speed fast enough could the centrifugal force would keep you up?

I did think about the bike with the fixed fork, and what would happen if you couldnt turn the bars. but im not completely sure this is the best example, since the wheenls arent "fixed" as well.

But I have seen other things that work in a similar fashion, such as roller blades, skis, and Im trying to think of others. (actually I also did contemplate using roller blade wheels in front instead of a bicycle style wheel.

(oh and the rims would be mainly aluminum, not steel)

On the other hand, As far as balance, what if the fork was fixed but the handle bars were not, so that you could lean the bike but not turn to get balance while the bike would will follow the rail?


(I'm a fairly experienced rider, have even done a little trick riding, so I know a little about balancing on 2 wheels(and sometimes one)

Now also if I make a rim that has 2 contact points at the edge of the rail, would that aid in keeping upright?

can anyone else think of other examples of similar things?
OR simple ways to carry out some tests?
(one idea I had was to simply take a regular bike, take the tires off and get a long tube of steel and try and ride on it)


Lastly i did find this:
http://www.emeraldempireadventures.com/wordpress/t...

I'm working on it!

RE: Railroad Bicycle

Quote:

Now also if I make a rim that has 2 contact points at the edge of the rail

Once again, rail in the real world does not look like the rail in your picture. It wears.



RE: Railroad Bicycle

(OP)
ok thanks will try and keep it in mind, but I think that will be relatively minor in the whole scheme

I'm working on it!

RE: Railroad Bicycle

It will not work. Centrifugal force doesn't "keep you up". It's gyroscopic precession that resists the falling torque created by gravity and helps you stay up somewhat. Steering is required to maintain balance by "steering" the bike up underneath you. Have you ever gotten your bike stuck in a rut? You can't steer out of it. You can't steer the bike and maintain it underneath you. Therefore you fall. A steel rail is absolutely no different.

Lots of really cool inventions have been made by people who were told it was impossible. Unfortunately, this is not one of those cases.

-handleman, CSWP (The new, easy test)

RE: Railroad Bicycle

There have been RR bikes way back in the 1850s or so. They used an outrigger on the opposite rail and were adjusted to have a very slight lean into that side. They used a flanged wheel design to stay on the main rail.
Stories I have read about these are that the signal repair guys could cover large amounts of rail in a short time with them.

Red has a good point that unless you are an employee of the railroad, you will be trespassing as soon as you put this thing on the rail. The groups that use the little track scooters have to work for months with the railroads to get permission for just a couple hour ride. No railroad is going to want you on the track with their trains; will you be hooked into the Central Train Control system?

RE: Railroad Bicycle

I think you should go ahead and try it. There's nothing like experience to teach you when something is actually is impossible as compared to merely impractical. As people have mentioned you have some major hurdles to jump. Not only getting a bike that works but then finding tracks that you can ride on (preferably without a train running into you) while maneuvering around all the obstacles that others have mentioned.

RE: Railroad Bicycle

If you want a rail-capable bike because you can (maybe) go places a normal bike can't, that's one thing. But it sounds more like you are just trying to make a more efficient bike. What's the point of eliminating the rolling resistance in search of efficiency, only to add additional (rotational) weight and maybe a trailer to carry roadworthy wheels and tires? If you are seeking efficient return on your energy expenditures, and not just a likely-very-illegal adventure, I think you will be poorly disappointed. A modern, lightweight, properly geared road bike is a pretty freaking efficient machine. I have a hard time seeing how adding 25 pounds is going to make things better.

RE: Railroad Bicycle

Dissapointing to see that nobody has tried to estimate the increase in speed by eliminating the rolling resistance from the tires.

Roughly speaking Crr best race tire 0.0025 Crr typical railway wheel 0.0010 to 0.0024

Now imagine what the Crr of an inverted V section on the rail is likely to be, I'd guess the upper end of the range for normal railway wheels.

Cheers

Greg Locock


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RE: Railroad Bicycle

Rolling resistance of good HP tire << gravity and drag.

RE: Railroad Bicycle

I thought about pedal rail quad-cycle several years ago. I often drove on a rural highway and there was a rarely used track that ran beside parts of it. The rail line veered off through much more interesting scenery, ran along a river and through some big ranches, places the general public couldn't access.

My thought / scheme / notion at the time was to make polyurethane wheels shaped sort of like the railcar wheel MintJulep shows, though narrower than the top of the rail and with less of a flange. I was thinking along the lines of making it very light and easy to throw off the tracks and into the bushes if I did hear a train coming. They only seemed to run maybe 3 times a week on that line, "seemed" being the operative word. I just wanted to get outdoor cycling leg exercise without dodging traffic and to get out into the countryside of those remote stretches of rail.

I was thinking of arch frames with a webbing seat suspended on bungee cords for shock absorption, a "recumbent bike" type pedaling position where you're actually sitting down hung below the frame.

RE: Railroad Bicycle

(OP)
Thank you all.

RE: Railroad Bicycle

Your example is a demonstration of the impossibility of your intent: the acrobat can ride on a bicycle with fixed front wheel only owing to the long bar he's in his hands. This is the device that replaces the steering effect in maintaining equilibrium at low speed. At higher speeds the gyroscopic effect helps, but is not sufficient alone: steering is still required to recover the right path when something drives you (the front wheel) out of it, e.g. a pebble or a small hole or a side slope.
Your idea of using a standard bicycle without tires on a long tube is the right one to test.

prex
http://www.xcalcs.com : Online engineering calculations
http://www.megamag.it : Magnetic brakes and launchers for fun rides
http://www.levitans.com : Air bearing pads

RE: Railroad Bicycle

here is a summary of railroad tresspass laws in every state published by the FRA (Federal Railroad Administration), though it may be out of date. Things have goten worse post-9/11. Every train has a radio, and every railroad maintains it's own police force.

http://www.fra.dot.gov/downloads/safety/cross_chp9...

RE: Railroad Bicycle

I am with Berskshire on this outrigger concept. A motorized bike would make more sense.

RE: Railroad Bicycle

chicopee,
The scary thing about a picture like that, is that the sweet young thing sitting on the bike, is probabaly old enough to be your great grandmother.
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor

RE: Railroad Bicycle

Don't forget Berkshire, these great grand old folks were also smart and you can see that by their machines they developed as you have seen in the rest of the pack of my attachment. Much of what we know today is due to their intelligence.

RE: Railroad Bicycle

Yea,
I was thinking about that.
I was looking at the picture of the Amphicar on a stretch of the river avon where I used to sail 40 years ago (ATT000999).
That picture does not look so old, or is it me?
B.E.

The good engineer does not need to memorize every formula; he just needs to know where he can find them when he needs them. Old professor

RE: Railroad Bicycle

That bicycle the gal is on is what was referred to as an Irish Mail when I was young. The handlebars cycle back-and-forth to drive a crankshaft on the rear wheel.

There are many abandoned rail lines in the USA, some go thru very nice country, too. But they are likely in such poor shape that rail spacing is compromised, the roadbed choked with weeds and trees, etc.

But Moon161 hit the nail on the head, wind resistance is the dominant force to overcome in cycling. ASME magazine had an article on this about 20 years ago.

RE: Railroad Bicycle

Most lines, when truly abandoned, have the rails pulled up for scrap, they're worth money.

A standard road bike has VERY low rolling resistance- you're on skinny little tires with 120 psi or so. If you eliminated ALL the rolling resistance, it wouldn't be that much different. And if you had to put a metal wheel 3" wide on there to say on the rail, the wind drag and weight would offset any gains in rolling efficiency.

RE: Railroad Bicycle

There is one factor in favor which I have not seen mentioned as yet:

Rail lines never climb very steeply. Or descend.

Regards,

Mike

RE: Railroad Bicycle

Mike, that's a mark against the idea, not in favor of it.

RE: Railroad Bicycle

Its been mentioned a few times that the rolling resistance is very low for thin tires and there would not be much improvement on a rail, but how about the small bumps that cause a slight change in momentum. It is common advice to keep tire pressure limited to 120 psi so that the tire can deform over small bumps as the resistance due to change in momentum is greater than the rolling resistance. Would there be a noticeable improvement here?

However I like this idea. I was/am more heavier rider/racer more of a classics/criterium rider and like the idea of hammering down a perfectly smooth track. Only problem is that the tracks are too busy where I live!

EIT
www.HowToEngineer.com

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