Holie Crappy MPG's, Batman!

LongRanger_imp said:
I rarely ride below 8,000'. Less oxygen at altitude means less fuel is required to maintain the stoichiometric ratio. Or something like that.
Click to expand...
Carguy1959_imp said:
My current altitude is 201ft. I have never got better than 42mpg. My bike also has always run rich.
Click to expand...

My new phone has a compass and an altimeter in it. After reading this thread I pulled it out to see what the elevation I normally ride at

800'. That's 600 feet above Carguy, but a whopping mile and a half below LongRanger. Amazing.
 
I live at around 350 feet and I weigh 165 pounds. This winter I've ridden between 350 and 1500 feet. today's ride 150.3 miles and 55.8 mpg. This month 1445 miles at 52.2 mpg.
Kevin
 
There is no legitimate reason for such vast different mpg (especially on the high side) other than driving style & speed or there must be something messed up in the FI or computer. Science is science.

Speaking of which - Altitude. When one goes up the air gets thinner. There are basically 3 types of aircraft engine types - reciprocating, turboprop and turbo fan. Very few turbo jets outside of 3rd world, but even those are disappearing due to fuel costs. Recips function best down low, turbo fans are actually a combination of a many bladed shrouded turboprop (80%) with a turbojet (20%) and function the best the higher they go due to the decreased wind resistance on the airframe - it has nothing to do with the engine. Turboprops are the best in the middle altitudes to low high altitudes.

Recips die as the altitude goes up and need to lean out or they will foul. Our bikes do not go fast or high enough to take advantage of the less dense air at altitude on the scale of jets. One has to go to 18,000feet up before the air density drops in half. It only drops 17% to 5,000, but at 40,000 it has dropped over 5 fold (81.5%). It is the air resistance removal that is responsible for the higher "mpg" and increased speed. The different engine and propulsion types are strictly enabling combustion as air density decreases.

Back to our CB & altitude - Our bikes will lean out accordingly via the FI/computer, but it will take a larger throttle movement to enable the same amount of fuel to be consumed to produce the power required for the given load. Think of it this way - every gallon of gasoline has XXX amount of energy in it. To produce a given net load (speed for a specific weight) an exact amount of gasoline needs to be consumed. It doesn't matter if it is on a Harley or a CB or an auto. The different mpgs are a result of their mass speeds and how efficiently they transfer the energy consumed to the propulsion. For similar CB models, the mpgs should be nearly identical at the same speed with the same rider weight. When starting, stopping, driver weight & behavior are non-similar, the numbers are all over the place like on this thread.
 
Ran ethanol free fuel. - got shade over 55 mpg.
Regular gas - 52 mpg.
No drastic changes between rides. Similar weather, terrain, altitude, and speed.
 
Thread starter
For the record the title of this thread should be "Holie Crappy..." Holie as in full of holes. Somehow it kept fixing itself...
 
:rofl: really? That's my fault. I thought "Holy" was misspelled and it bothered me so I fixed it. I will un fix it. Sorry about that.

Sometimes there are spelling errors in titles and being an associate editor in another life, I naturally fix them.
 
Thread starter
The ferret_imp said:
:rofl: really? That's my fault. I thought "Holy" was misspelled and it bothered me so I fixed it. I will un fix it. Sorry about that.

Sometimes there are spelling errors in titles and being an associate editor in another life, I naturally fix them.
Click to expand...
Ha! I knew it!! :rofl: It's how Robin (Chris O'Donnell) said it the first time in the horrible Batman Forever movie. "Holie rusted metal, Batman! It's full of holes." I don't know why I remember this stuff, I should use my memory space for useful things. :D

Nonetheless, thanks for watching out for my second language deficiencies. :thumbsup:
 
I've got a 2013 CB1100 with 2,200 miles. I have been averaging 46 on my commute to work, but I just got 40 mpg around town. Money is really not an issue, but I feel I'm always refueling.
 
Nemo_imp said:
The ferret_imp said:
:rofl: really? That's my fault. I thought "Holy" was misspelled and it bothered me so I fixed it. I will un fix it. Sorry about that.

Sometimes there are spelling errors in titles and being an associate editor in another life, I naturally fix them.
Click to expand...
Ha! I knew it!! :rofl: It's how Robin (Chris O'Donnell) said it the first time in the horrible Batman Forever movie. "Holie rusted metal, Batman! It's full of holes." I don't know why I remember this stuff, I should use my memory space for useful things. :D

Nonetheless, thanks for watching out for my second language deficiencies. :thumbsup:
Click to expand...
Same reason as I can remember stupid mnemonics from over 60 years ago but can't remember what Darling just now sent me to the shop for; was it lettuce or cabbage? Or maybe sugar. Aaaaarrrrgggh.

We need a forum shrink to be a SME on this sort of stuff. And sort out the *** threads.

Cheers
 
While on the subject of precision, may I commend you, Nemo, on the use of the grocers' apostrophe. Robin—ignorant sycophant that he is—would almost certainly have articulated it.
 
Thread starter
Cormanus_imp said:
While on the subject of precision, may I commend you, Nemo, on the use of the grocers' apostrophe. Robin—ignorant sycophant that he is—would almost certainly have articulated it.
Click to expand...
:blush: Aaargh!! I do it all the time. Will do my best to not do it again. Please remember I'm linguistically challenged in this Shakesperian system of communication. However, maybe all it took was to be publicly ashamed to never forget again. Thank's, Cormanus. :shy:

DUH!!! :s
 
:rofl: Nemos the man!
 
Nemo, when Cormanus puts on his Grammar Police uniform, just take a deep breath, a strong drink and a slice of this:

393a1c2b17745500766f7b598625ba03.jpeg


Cheers
 
Nemo? He's a great bloke. It's that twat Robbin I was having a go at.
 
You must log in or register to reply here.

Similar threads

rdprdp01
2019 West Coast Rally Plans (Recreation)
Replies
0
Views
330
rdprdp01
rdprdp01
Back
Top