Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Foo Off-Topic chit chat with no general subject.

Reply
 
Thread Tools Search this Thread
Old 07-12-08, 10:14 AM   #26
Allen
Senior Member
 
Join Date: Sep 2005
Bikes:
Posts: 4,753
In Ga 55mph is impeding traffic.
Allen is offline   Reply With Quote
Old 07-12-08, 10:40 AM   #27
chrisvu05
Legs of Steel
 
chrisvu05's Avatar
 
Join Date: Jun 2005
Location: On my bike
Bikes: Pegoretti Marcelo, Cannondale six13
Posts: 1,833
I can't believe it hasn't been said......

I CAN'T DRIVE FIFTY-FIVE!!! (yelled in rocker voice of Sammy Hagar)
chrisvu05 is offline   Reply With Quote
Old 07-12-08, 10:47 AM   #28
donnamb 
tired
 
donnamb's Avatar
 
Join Date: Apr 2006
Location: Portland, OR
Bikes: Breezer Uptown 8, U frame
Posts: 5,652
Quote:
Originally Posted by wyeast View Post
Not much around here where you can drive faster than 60 w/o risking a ticket.
You say that like it's a bad thing.
__________________
"Real wars of words are harder to win. They require thought, insight, precision, articulation, knowledge, and experience. They require the humility to admit when you are wrong. They recognize that the dialectic is not about making us look at you, but about us all looking together for the truth."
donnamb is offline   Reply With Quote
Old 07-12-08, 10:57 AM   #29
timmyquest
Banned.
 
timmyquest's Avatar
 
Join Date: May 2005
Location: Woodstock
Bikes:
Posts: 5,761
Quote:
Originally Posted by JoelS View Post
Driving slower may not help your gas mileage. It depends on how your particular car is tuned. Many get their best mileage at 65 or 70.

Just like when you're pedaling (optimum gear/cadence for you), there is an optimum efficient speed for your car.
Considering most cars shift into overdrive well before 55 and considering wind is greater at speed...i'm gonna disagree with this here now there um now here there
timmyquest is offline   Reply With Quote
Old 07-12-08, 01:03 PM   #30
RCordone
cyclopath
 
Join Date: Mar 2008
Location: NY
Bikes:
Posts: 149
My wife's Volvo wagon gets it's best mileage(33 mpg) at or a little over 65 mph. My 6cyl/5spd F150 gets it's best mileage(23mpg) between 52 and 55 mph.

I like doing 52 mph on the Sawmill River Parkway(I-87). I single handedly piss off more motorists in one day than a hundred Critical Mass-holes can piss off in a whole year
RCordone is offline   Reply With Quote
Old 07-12-08, 01:10 PM   #31
crackerjab
WTF is that smell?
 
crackerjab's Avatar
 
Join Date: Dec 2005
Location: Charlotte, NC
Bikes:
Posts: 449
Quote:
Originally Posted by JoelS View Post
Driving slower may not help your gas mileage. It depends on how your particular car is tuned. Many get their best mileage at 65 or 70.

Just like when you're pedaling (optimum gear/cadence for you), there is an optimum efficient speed for your car.
+1

I drive 4000+ miles a month in various rental cars. A lot of these cars have real time mpg indicators. We'll call it an ongoing experiment of mine. Some of these cars get their better mpg at 72mph than they do at 55mph. Some of them get better mpg at 85mph than 35mph. That being said, it's the opposite with other cars. Different cars are efficient at different speeds and different conditions. But as general rule of thumb, I drive 95mph on low congestion interstates. And 90mph in when going through GA so I don't get ran over.

Another fun thing to do is find other drivers going as fast as you and take turns drafting. You'd be surprised the difference in fuel economy.
crackerjab is offline   Reply With Quote
Old 07-12-08, 01:14 PM   #32
PhilThee
Downhill Racer
 
PhilThee's Avatar
 
Join Date: Jan 2006
Bikes: 1994 Bridgestone RB1, 2006 Cannondale R1000, 2007 Cannondale Caad9 Optimo2
Posts: 739
Quote:
Originally Posted by x136 View Post
and since Californians are completely clueless of the "keep right except to pass" concept, trying to drive faster is just an exercise in stress and frustration anyway.

You aren't alone there. It's the same in Oregon.

If I'm in a gas saving mood I drive just fast enough so that no Semi's pass me. That's just irritating.

I don't know if this saves me any gas though because I eventually get trapped behind someone who doesn't know how to drive at a steady speed

60-62-55-70 MAKE UP YOUR MIND FOR CHRISTS SAKE!!!!!!!!
__________________
"I didn't see him/her" is a confession, not an excuse.
PhilThee is offline   Reply With Quote
Old 07-12-08, 01:14 PM   #33
crackerjab
WTF is that smell?
 
crackerjab's Avatar
 
Join Date: Dec 2005
Location: Charlotte, NC
Bikes:
Posts: 449
Quote:
Originally Posted by timmyquest View Post
Considering most cars shift into overdrive well before 55 and considering wind is greater at speed...i'm gonna disagree with this here now there um now here there
So are you saying that your because your car shifts into OD at say, 40mph, that is your optimum speed for the best mpg?

It's using more power when it first shift into overdrive.
crackerjab is offline   Reply With Quote
Old 07-12-08, 01:18 PM   #34
crackerjab
WTF is that smell?
 
crackerjab's Avatar
 
Join Date: Dec 2005
Location: Charlotte, NC
Bikes:
Posts: 449
Quote:
Originally Posted by PhilThee View Post
You aren't alone there. It's the same in Oregon.

If I'm in a gas saving mood I drive just fast enough so that no Semi's pass me. That's just irritating.

I don't know if this saves me any gas though because I eventually get trapped behind someone who doesn't know how to drive at a steady speed

60-62-55-70 MAKE UP YOUR MIND FOR CHRISTS SAKE!!!!!!!!
That drives me absolutely crazy when people do that. My favorite is when they pass you, then slow down, then you pass them (because you're at the same rate of speed), then they speed up again, and the cycle continues.
crackerjab is offline   Reply With Quote
Old 07-12-08, 01:22 PM   #35
PhilThee
Downhill Racer
 
PhilThee's Avatar
 
Join Date: Jan 2006
Bikes: 1994 Bridgestone RB1, 2006 Cannondale R1000, 2007 Cannondale Caad9 Optimo2
Posts: 739
Quote:
Originally Posted by Wordbiker View Post
I drive 55 because the guy in front of me can't see the limit sign that clearly says 65MPH and won't pull over for faster traffic.
The answer is a simple one.

He's in the middle or far left lane because,

He's not driving a Semi Truck so he's doing the right thing while costing everyone else mpg because they have to slow down for him and then get back on the gas.

He's on the phone and can't be bothered with the rules of the road at this time?

He's clueless and has been since birth?

Maybe this should be a pole
__________________
"I didn't see him/her" is a confession, not an excuse.
PhilThee is offline   Reply With Quote
Old 07-12-08, 01:29 PM   #36
PhilThee
Downhill Racer
 
PhilThee's Avatar
 
Join Date: Jan 2006
Bikes: 1994 Bridgestone RB1, 2006 Cannondale R1000, 2007 Cannondale Caad9 Optimo2
Posts: 739
Quote:
Originally Posted by crackerjab View Post
That drives me absolutely crazy when people do that. My favorite is when they pass you, then slow down, then you pass them (because you're at the same rate of speed), then they speed up again, and the cycle continues.
EXACTLY what I'm talking about!

I usually end up kicking up the speed for a few miles then slowing down to where I was.
Do I save gas with that move, well no.
But I do save my piece of mind.
__________________
"I didn't see him/her" is a confession, not an excuse.

Last edited by PhilThee; 07-12-08 at 01:58 PM.
PhilThee is offline   Reply With Quote
Old 07-12-08, 02:02 PM   #37
phantomcow2
la vache fantôme
 
phantomcow2's Avatar
 
Join Date: Aug 2004
Location: NH
Bikes:
Posts: 6,266
No I don't do 55; I'd be ostracized from the road if I did that. I find anywhere from 60-65 to be a fair compromise, and I do get very good fuel economy in this range. My car starts to shake past 65 anyways.
__________________
C://dos
C://dos.run
run.dos.run
phantomcow2 is offline   Reply With Quote
Old 07-12-08, 02:14 PM   #38
timmyquest
Banned.
 
timmyquest's Avatar
 
Join Date: May 2005
Location: Woodstock
Bikes:
Posts: 5,761
Quote:
Originally Posted by crackerjab View Post
So are you saying that your because your car shifts into OD at say, 40mph, that is your optimum speed for the best mpg?

It's using more power when it first shift into overdrive.
I'm saying that in a given gear it takes more throttle to go faster. More throttle means more gas.
timmyquest is offline   Reply With Quote
Old 07-12-08, 02:19 PM   #39
Ih8lucky13
The Truth
 
Ih8lucky13's Avatar
 
Join Date: Apr 2006
Location: Miami
Bikes: Felt f4c, Felt RXC, Guerciotti Khaybar,Guerciotti EM-2, Cervelo P-3.
Posts: 2,290
My time is way too valuable to worry about saving a few pennies to slow down.
Ih8lucky13 is offline   Reply With Quote
Old 07-12-08, 02:20 PM   #40
ricebowl
Bourbon junkie
 
ricebowl's Avatar
 
Join Date: Aug 2007
Location: NorCal
Bikes:
Posts: 713
hell no...65-80.
ricebowl is offline   Reply With Quote
Old 07-12-08, 02:44 PM   #41
supton
Cries on hills
 
supton's Avatar
 
Join Date: Jun 2007
Location: Central NH
Bikes: 2007 Trek Pilot 1.2, 1995 Gary Fisher Avantage, 1985 Panasonic Sport 1000, 1969 Raleigh Sprite 5
Posts: 877
Unfortunately, 2/3's of my annual milage comes from commuting back and forth to work. So, I've tried to slow down, driving maybe 5mph under. Gets me that last 10% in FE, bumps it up to 50 or so. I gave in and bought a Scangauge, partially so I could read problem codes (if and when they pop up) but mostly 'cuz I really wanted to see what kind of mpg I was getting, real time.

That said, with the family loaded up, I sometimes will go whatever speed it takes to hold the left lane. If that gets too fast for me (typically 90mph or 25 over, whichever comes first), I'll move over another lane. But the real crazies seem to live in the right(er) lanes. Speed up/slow down sorts, the guys who can't be bothered to slow down and would pass you in the ditch at 50 over, people who can't merge--by driving fast enough to hold the left lane (or middle one), I find my blood pressure stays lower. Plus, with the kids, I have plenty of encouragement to make 3+ hour trips shorter by any means.
supton is offline   Reply With Quote
Old 07-12-08, 02:50 PM   #42
supton
Cries on hills
 
supton's Avatar
 
Join Date: Jun 2007
Location: Central NH
Bikes: 2007 Trek Pilot 1.2, 1995 Gary Fisher Avantage, 1985 Panasonic Sport 1000, 1969 Raleigh Sprite 5
Posts: 877
Quote:
Originally Posted by crackerjab View Post
I drive 4000+ miles a month in various rental cars. A lot of these cars have real time mpg indicators. We'll call it an ongoing experiment of mine. Some of these cars get their better mpg at 72mph than they do at 55mph. Some of them get better mpg at 85mph than 35mph.
I find that hard to believe. Wind resistance goes up as the square of speed. I could believe 65mph would get more mpg's than 35, if only because of being in top-gear -- but not 85 vs 35. Are you sure you're not comparing instantaneous mpg readout? Accelerating at 35 would burn more gas than maintaining speed at 85, no doubt.

Question: given 4k/month in driving time, you probably have to fill up any particular car a few times, no? Have you compared the calculated by hand method vs whatever the cars computer thinks it got for the tank? I've heard many complaints (all the web, granted) that those real time readouts are pretty optimistic--but that they have gotten much better in recent years.
supton is offline   Reply With Quote
Old 07-12-08, 06:23 PM   #43
crackerjab
WTF is that smell?
 
crackerjab's Avatar
 
Join Date: Dec 2005
Location: Charlotte, NC
Bikes:
Posts: 449
Quote:
Originally Posted by supton View Post
I find that hard to believe. Wind resistance goes up as the square of speed. I could believe 65mph would get more mpg's than 35, if only because of being in top-gear -- but not 85 vs 35. Are you sure you're not comparing instantaneous mpg readout? Accelerating at 35 would burn more gas than maintaining speed at 85, no doubt.

Question: given 4k/month in driving time, you probably have to fill up any particular car a few times, no? Have you compared the calculated by hand method vs whatever the cars computer thinks it got for the tank? I've heard many complaints (all the web, granted) that those real time readouts are pretty optimistic--but that they have gotten much better in recent years.
The 85 versus 35 making a point about the differences in different vehicles. And those mpg indicator are not always entirely accurate. Close but not always. And yeah I get actual results when filling by how much gas vs how many miles driven give or take a quarter gallon. Mostly what I'm getting at here is that some cars can be more efficient at speeds in the 65 70 range versus the 55 mark.
crackerjab is offline   Reply With Quote
Old 07-12-08, 06:42 PM   #44
qmsdc15
Banned
 
Join Date: Mar 2004
Location: Maryland
Bikes: rockhopper, delta V, cannondale H300, Marin Mill Valley
Posts: 5,155
I have always driven at or below the posted limit. This thread has inspired me to drive at or below 90% of the maximum legal speed from now on, to stay ahead of the trend. I believe in setting a good example for those less intelligent than myself.
qmsdc15 is offline   Reply With Quote
Old 07-12-08, 07:27 PM   #45
Wordbiker
Pwnerer
 
Wordbiker's Avatar
 
Join Date: Jun 2005
Location: Pagosa Springs, CO, USA
Bikes: Road, MTB, Cruiser, Chopper, BMX
Posts: 2,906
Quote:
Originally Posted by qmsdc15 View Post
I believe in setting a good example for those less intelligent than myself.
Yes, but will he notice?
__________________
Quote:
Originally Posted by ahsposo View Post
Ski, bike and wish I was gay.
Wordbiker is offline   Reply With Quote
Old 07-12-08, 09:11 PM   #46
cydewaze
Emondafied
 
cydewaze's Avatar
 
Join Date: May 2005
Location: Maryland
Bikes: See sig
Posts: 4,770
Quote:
Originally Posted by supton View Post
I find that hard to believe. Wind resistance goes up as the square of speed. I could believe 65mph would get more mpg's than 35, if only because of being in top-gear -- but not 85 vs 35. Are you sure you're not comparing instantaneous mpg readout? Accelerating at 35 would burn more gas than maintaining speed at 85, no doubt.
While I can't vouch for anyone else's car, I had a similar experience with my old 95 Camaro. The car had a 6-sp manual transmission with a 0.5:1 ratio. I had also changed the wheels/tires, and the new ones were a bit taller than stock.

At 55mph, RPM in 6th gear was around 900 - way too low for efficient running. Any uphill grade, even a slight one, would cause the car to buck, lurch, and foul plugs. So 55mph meant 5th gear and much higher RPM. Increasing speed to 65-70 would get you around 1500-1800 in 6th gear, which gave me much better economy than 55mph in 5th. I even managed to pull 30mpg on one trip, with the AC blasting and a few occasional blasts of the throttle while accelerating on on-ramps. Not bad for a 5.7 liter V8.
__________________

my bike page - my journal
Current Stable: Trek Emonda SL - Trek Top Fuel 8 - Scattante XRL - Jamis Dakar Expert - Trek 9700 - [strike]AlpineStars Al Mega[/strike]
cydewaze is offline   Reply With Quote
Old 07-12-08, 09:45 PM   #47
timmyquest
Banned.
 
timmyquest's Avatar
 
Join Date: May 2005
Location: Woodstock
Bikes:
Posts: 5,761
Quote:
Originally Posted by crackerjab View Post
The 85 versus 35 making a point about the differences in different vehicles. And those mpg indicator are not always entirely accurate. Close but not always. And yeah I get actual results when filling by how much gas vs how many miles driven give or take a quarter gallon. Mostly what I'm getting at here is that some cars can be more efficient at speeds in the 65 70 range versus the 55 mark.
It is accurate but as mentioned, going forward from a stop =/= cruising at Xmph
timmyquest is offline   Reply With Quote
Old 07-12-08, 09:46 PM   #48
timmyquest
Banned.
 
timmyquest's Avatar
 
Join Date: May 2005
Location: Woodstock
Bikes:
Posts: 5,761
Quote:
Originally Posted by cydewaze View Post
While I can't vouch for anyone else's car, I had a similar experience with my old 95 Camaro. The car had a 6-sp manual transmission with a 0.5:1 ratio. I had also changed the wheels/tires, and the new ones were a bit taller than stock.

At 55mph, RPM in 6th gear was around 900 - way too low for efficient running. Any uphill grade, even a slight one, would cause the car to buck, lurch, and foul plugs. So 55mph meant 5th gear and much higher RPM. Increasing speed to 65-70 would get you around 1500-1800 in 6th gear, which gave me much better economy than 55mph in 5th. I even managed to pull 30mpg on one trip, with the AC blasting and a few occasional blasts of the throttle while accelerating on on-ramps. Not bad for a 5.7 liter V8.
Just because you don't know how to drive a stick shift doesn't mean that the car is more efficient at 65mph...
timmyquest is offline   Reply With Quote
Old 07-13-08, 04:27 AM   #49
Stacey
Non Tribuo Anus Rodentum and off to the next adventure (RIP)
 
Stacey's Avatar
 
Join Date: Dec 2002
Bikes:
Posts: 9,162
Quote:
Originally Posted by crackerjab View Post
Another fun thing to do is find other drivers going as fast as you and take turns drafting. You'd be surprised the difference in fuel economy.
That's just sheer lunacy.

Did you ever integrate the 'what if' variable on to your calculations?
__________________
Stacey is offline   Reply With Quote
Old 07-13-08, 08:18 AM   #50
Mike R.
Member
 
Mike R.'s Avatar
 
Join Date: Jul 2008
Location: West Trenton, NJ
Bikes:
Posts: 31
Quote:
Originally Posted by veggie_lover View Post
I have learned from cycling that you can move well below the speed limit, and not be a hindrance to traffic or compromise your safety. So with high gas prices I have taken to driving 55 on interstates since my car gets 15% better gas mileage compared to going 70. I found this site has a useful calculator to determine your savings per hour by driving slower. Anyone else driving slower because of high gas prices?

Depends on the car actually.

My current car (Audi A4 2.0T Quattro) likes 65 mph in 5th for the best gas mileage. Drop it to 6th and it suffers. In 4th, same thing. 5th/65mph works best on the highway for me.

My old car (Porsche Bosxter) liked 4th gear at about 110mph. Well...that's a lie....I liked it, gas be damned in that car! LOL.
Mike R. is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 03:45 PM.