Motorway slipstream
Discussion
This was done on Mythbusters a couple of years back:
http://green.autoblog.com/2007/10/28/mythbusters-d...
Quite interesting results...
Chris
http://green.autoblog.com/2007/10/28/mythbusters-d...
Quite interesting results...
Chris
MR2 Jon said:
True, you'd need to break the recommended safety gap of 2secs to see any gains but I'd say 100ft (30m) is about average in reality.
Also the gain would increase exponentially with speed and SUVs tend to go a lot faster than lorry's.
Only about a quarter of the frontal area though.Also the gain would increase exponentially with speed and SUVs tend to go a lot faster than lorry's.
The gap (distance) will increase with speed but the time gap will remain similar and the faster you go the riskier it is to get close to someone else.
i just don't see the gain in fuel economy being worth the increase in risk of safety.
A quarter sounds a little conservative but, yeah, I'm not sure what bearing the speed/distance ratio would have on MPG.
Fair enough, I not suggesting anyone goes and does it, I'm wondering more just out of interest. Guess it's better to be following something big than in clear air though, if your trying to maximize MPG.
Fair enough, I not suggesting anyone goes and does it, I'm wondering more just out of interest. Guess it's better to be following something big than in clear air though, if your trying to maximize MPG.
Hooli said:
Oddly enough I hate it on the bike, it's just all blustery & comfy. Maybe your getting a lot closer than I do though?
not at all, 2 second rule obeyed at all times! (4 seconds when wet!) you can stay quite a distance away to benefit aslong as its a high vehicle.tbh i hate riding at speed. get bloody blown all over. much rather be on a long winding road!
k15tox said:
Hooli said:
Oddly enough I hate it on the bike, it's just all blustery & comfy. Maybe your getting a lot closer than I do though?
not at all, 2 second rule obeyed at all times! (4 seconds when wet!) you can stay quite a distance away to benefit aslong as its a high vehicle.tbh i hate riding at speed. get bloody blown all over. much rather be on a long winding road!
It may just be the fairing on my current commuting bike that causes it, I don't recall the buffeting on naked bikes. Unfortunately a crap neck over last winter caused the purchase of a screen (with fitted bike
) & it's turned out to pay for itself in cheaper servicing & higher MPG so it's stayed.Many years ago when i had a 200cc Suzuki i was trevelling down the M4 when i went on to reserve,i know i had about 10 miles left of fuel.So being a bit stupid i did exactly this ,slip streamed a lorry and got tugged along as to get me to the next fuel stop with out this i know i would have run empty.I know i was far too close and as i said young and a bit stupid but it save me walking miles to get a gallon of fuel.
JTXenon said:
I tried it with a lorry once... ONCE never again
Perhaps you were behind me. I hate it when cars slipstream/tailgate me and I will do everything I can to prevent it.I will stray onto the hard shoulder if it's clear to kick up the debris, which usually deters most people but the more determined drivers had better be awake because I *will* stand on the brakes.
I carry a high-value load and have had two attempted high-jackings in the past, so I am extremely suspicious if a car follows me at 53mph on a motorway mile after mile.
Do *not* slipstream trucks, it is extremely dangerous...especially if you're behind me.
On one incredible occasion I found myself, in an 1100CC 107 BHP Brabham FJ, right up behind a group of 3 tightly packed 2.5L F1s, coming into Hume straight at Warwick Farm Sydney.
They towed me up to 25 MPH higher speed than the car could get by itself, with me using only about 1/3 throttle. I stayed right behind them for a full lap, & it was only when they separated a bit that they dropped me.
In the 1964 Armstrong 500, [Bathurst 500], I had a Triumph 2000 tow me, in a Hillman Imp, up to 107 MPH electrically timed through the flying 1/8Th down Conrod Straight. The speed was so remarkable, [the Imp only did 79MPH by itself] that it made the front page of the Sydney Morning Herald the next day. I often wondered how many people were disappointed when their Imp wouldn't do 100 MPH after that headline.
In 1967 I had another team transporting my car for me, & my crew & I would often drive from Sydney to Melbourne over night. We often used a new Ford Falcon. It could struggle up to almost 90MPH on its own, 3 or 4 up, on the long Victorian straights.
In those days of no top speed limit the better pantechnicon body trucks & semis were getting up to a bit over 105 MPH. We could not catch a tow when they passed us, but we could accelerate with them into a straight no problem. Provided we stayed within about 30FT of them they would tow us up to 105/108 no trouble. At this speed it required practically no throttle on the Ford to stay there.
As someone said, it was a bit hairy. Our truckers didn't seem to mind at all, but with its drum brakes, the Ford could only give one stop, or even sever slowing, about every 10 miles or so. Even then it might run totally out of brakes at about 10 miles per hour, & just not stop, without us turning the engine off in gear.
Life was fun 50 years ago.
They towed me up to 25 MPH higher speed than the car could get by itself, with me using only about 1/3 throttle. I stayed right behind them for a full lap, & it was only when they separated a bit that they dropped me.
In the 1964 Armstrong 500, [Bathurst 500], I had a Triumph 2000 tow me, in a Hillman Imp, up to 107 MPH electrically timed through the flying 1/8Th down Conrod Straight. The speed was so remarkable, [the Imp only did 79MPH by itself] that it made the front page of the Sydney Morning Herald the next day. I often wondered how many people were disappointed when their Imp wouldn't do 100 MPH after that headline.
In 1967 I had another team transporting my car for me, & my crew & I would often drive from Sydney to Melbourne over night. We often used a new Ford Falcon. It could struggle up to almost 90MPH on its own, 3 or 4 up, on the long Victorian straights.
In those days of no top speed limit the better pantechnicon body trucks & semis were getting up to a bit over 105 MPH. We could not catch a tow when they passed us, but we could accelerate with them into a straight no problem. Provided we stayed within about 30FT of them they would tow us up to 105/108 no trouble. At this speed it required practically no throttle on the Ford to stay there.
As someone said, it was a bit hairy. Our truckers didn't seem to mind at all, but with its drum brakes, the Ford could only give one stop, or even sever slowing, about every 10 miles or so. Even then it might run totally out of brakes at about 10 miles per hour, & just not stop, without us turning the engine off in gear.
Life was fun 50 years ago.
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