bike trailer

[MetroMPG]

Just posted a new page at metrompg about...

How the cargo trailer I made for my beater 10-speed bike is hurting my MPG

http://www.metrompg.com/posts/bike-trailer.htm

[kickflipjr]

What did you use as the hinge to connect to the bike? I am interested because bike trailers are expensive +$100.

[MetroMPG]

Same thing as my brother's kiddie trailer - a stout spring, the ends held in steel tube. If you click into the article on metrompg.com, there's a zoom in pic that shows the hinge close up.

[Jack]

Well done! I really like it. I may have to try building one this winter when I am cooped up with nothing else productive to do.

[MetroMPG]

If you're going to weld/braze zinc-coated EMT conduit for the frame, best to do it outside with a breeze (or fan) :)

[kickflipjr]

Yeah If read the artical that would help insted of looking at the one picture you have in gassavers :D

I WILL be making one of these. I have some spare 26" wheels They might be tall but will do the job.

[Matt Timion]

It took me a minute to realize that when you (metric system people) say lower your MPG, you're actually increasing your MPG (by US terms).

[DaX]

It took me a minute to realize that when you (metric system people) say lower your MPG, you're actually increasing your MPG (by US terms).

Oh, hahaha. Me too Matt...I was thinking...and this is good because?

[kickflipjr]

????lower=higher????

[MetroMPG]

It took me a minute to realize that when you (metric system people) say lower your MPG, you're actually increasing your MPG (by US terms).
Nope, the trailer has made things lower in the MPG sense, not the L/100 km sense.

[MetroMPG]

I WILL be making one of these. I have some spare 26" wheels They might be tall but will do the job.

Cool!

[Matt Timion]

Nope, the trailer has made things lower in the MPG sense, not the L/100 km sense.

Because of the trailer, I use less fuel overall, true (and that's the important fact).

But by omitting some local driving (where I achieve my highest MPG figures), my driving is further biased towards highway use. As a result of the higher proportion of (lower MPG) highway driving, my calculated MPG for a given tank is lower than it would have otherwise been had I just driven the car locally instead of using the bike/trailer.

Ah! I guess I should have read the article before I made myself look like a fool :)

[DaX]

Ah! I guess I should have read the article before I made myself look like a fool :)

I rode the coat tails of your foolishness! :eek:

[lovemysan]

You must be in good shape. I have a rack and bags on my trek 7100 and it easily gets me winded. Its a nice aluminum framed hybrid.

[MetroMPG]

Not really. I just take it easy - it's all about the gearing :)

Plus, you don't want to be going too fast with 130 lbs worth of transmissions held on with bungee cords behind you.

[red91sit]

Not really. I just take it easy - it's all about the gearing :)

Plus, you don't want to be going too fast with 130 lbs worth of transmissions held on with bungee cords behind you.


If you get one of those bicycle odometers, you can measure how far you drive your bike, then add that into a new car in your garage (total travel/fuel) and see how much gas your saving by using the bicycle! I"m planning on doing this too.

[MetroMPG]

Neat idea. What's the "equivalent MPG" formula for bicycling though?

I actually did estimate how much I've used my beater bike since the beginning of this summer. It's approx 400 km of local trips.

[Silveredwings]

... you don't want to be going too fast with 130 lbs worth of transmissions held on with bungee cords behind you.

Chicken... :D (j/k)

(heck, that statement holds true for a stationwagon as well!)

[SVOboy]

Darin is just the coolest, end of story.

Anyway, I think someone posted a people/mpg thing a while back based on energy use.

[kickflipjr]

It looks like you could use some new handlebar tape and maybe a shiny new seat for your bike.

I might make something like darin did or I might build a one wheel trailer like this:

http://www.tomswenson.com/images/bob.jpg

[red91sit]

Neat idea. What's the "equivalent MPG" formula for bicycling though?

I actually did estimate how much I've used my beater bike since the beginning of this summer. It's approx 400 km of local trips.

haha, well if we could drink gasoline, or a liquid of equal caloric content per unit volume, we would get about 912 MPG average. In Tour De' France conditions, this drops to around 300 MPG.

But, we dont' drink gasoline haha, you could go through the horrendously difficult process of how much fuel is needed to create the extra food products you need to consume to bicycle. Well someone beat me to it, they range on average foods from 109 mpg, (average american diet) to 196 mpg for a vegetarian. Sooo, if Mr. Armstrong ate traditional american diet food's he should be getting about 36 miles for one gallon of gasoline, but we eat even if we don't bicycle. Soo these are all of no interest to me. I will be using the mpg calculation like this

Total miles (car, motorcycle, other car, bicycle)
--------Over--------
Total gasoline+Ethanol used (gallons)

An interesting quote i found on the web...

"It is actually quite astounding how much energy is wasted by the standard American diet-style. Even driving many gas-guzzling luxury cars can conserve energy over walking -- that is, when the calories you burn walking come from the standard American diet! (62) This is because the energy needed to produce the food you would burn in walking a given distance is greater than the energy needed to fuel your car to travel the same distance, assuming that the car gets 24 miles per gallon or better."4

[Ryland]

a friend of mine built a single wheeled trailer simaler style to the Bob Trailer, only it was built useing part of the front of a bike frame for the sub frame and pivit, then bent (cut and welded) the fork from the doner frame so it stuck forword to attach to the ridden bicycles rear axle, another fork was welded in to one of the frame tubes pointing back for the single wheel of the trailer to mount in to, then for the body of the trailer he made a box up out of foam, and covered it in carbon fiber, and disalved the foam, then by knowing the right people at the bike shop, got his hands on one of those 8 spoked (4 sets of blades) carbon fiber Spinergy wheels that had a busted spoke (clamped the wheel to remove tention on the busted spoke, and wraped it in more carbon fiber, fixing it, and truing it to near perfection) and of course he wanted to keep things in side this trailer weather tight, so a lid was made out of more carbon fiber (used up all the scraps at work from the boss building his air boat) and imbedded a 10 watt PV panal to keep a few batteries charged from a computer back up power suply, alowing him to run any 120v ac tool under 400 watts off the trailer, like his angle grinder, the whole set up is really impressive, I'll see if I can get photos from him at some point, sadly he built this shortly befor moving, so I didn't get a chance to take any photos.

[MetroMPG]

An interesting quote i found on the web...

This is because the energy needed to produce the food you would burn in walking a given distance is greater than the energy needed to fuel your car to travel the same distance, assuming that the car gets 24 miles per gallon or better."4

I've read something similar to that before. Problem is it seems to be comparing different things: [total energy to produce the food + the food energy itself] compared to [energy content of gas]. I think they'd have to also factor in the total energy to produce the gas to make it more apples to apples (no pun intended :) ).

[MetroMPG]

I'll see if I can get photos from him at some pointI'd like to see it if you can get pics.

The bob style trailers look slick.
Small points, but there you go.

[omgwtfbyobbq]

I think they'd have to also factor in the total energy to produce the gas to make it more apples to apples (no pun intended :) ).

It's minimal compared to the fossil fuel energy used in food. Something like 1.2:1 for gasoline compared to 10:1 for food, according to Pimental and co.

[Ryland]

if you are going to count the energy it takes to grow the food, then shouldn't you count the energy your body burns while driving as well? sure it's not as much as while you walk, but it's something, and it's also assuming that you are eating food that is not local, and that has been exsessivly pacaged, and prepared, but yes, a good deal of the money that goes in to producing food is fuel, the people that grow, and sell you your food get paid very little for the servic they are providing.

[omgwtfbyobbq]

There's a few ways to look at it. Personally, I figure riding ~10-15 miles each day is essentially combining exercise and transportation, so, good for you. The average American should worry about cholesterol/heart disease since it's what's most likely to kill them. Driving is minimal since it's just part of your base caloric demand, what you need to live including an hour of good exercise.... And every bit of biking past that depends on what you eat, how efficient you are at biking, and how efficient you are at driving to find out it's fossil fuel consumption. I'd wager MetroMPG requires about the same amount of fossil fuels to drive/bike, but getting an hour of exercise each day is very important, so biking is great in that respect. Otoh, if MetroMPG biked everywhere, it'd be a wash in terms of fossil fuel consumption, and there would be no 55mph, heater, etc...

When I see those infinity mpg t-shirts w/ a bike, I hang my head in shame. :thumbdown:
http://www.threadless.com//product/562/zoom.gif