Have you ever wondered if a manual-transmission car would reach the same top speed starting in high gear instead of low gear? Let’s break it down and find out! #ManualTransmission #CarGears #TopSpeed
Theoretical vs. Practical Approach
When thinking about this scenario in terms of a bike’s gears, it seems like the car would eventually hit the same top speed. However, the initial strain may affect the outcome.
Mechanics of a Manual Car
It all comes down to how manual cars are designed. The gears in a manual transmission are optimized for certain driving conditions, so starting in high gear may not be the most efficient way to reach top speed.
So, would a manual car reach the same top speed starting in high gear? What do you think? Let’s dig deeper into the mechanics and find out the answer! #CarMechanics #DrivingEfficiency #ManualTransmission101
Yes, assuming the transmission isn’t geared in such a way that the highest gears provide insufficient torque to overcome the inertia.
I had a manual truck, rwd. In icy conditions I’d often start in second gear, and sometimes even third.
Fifth gear was a struggle, but if I reved the motor high enough and feathered the clutch sufficiently it would move.
Your main difficulty will be not stalling the engine trying to get moving at all and while still at very low speed . You might be able to ride the clutch up to the point where you are going fast enough the engine can actually run without stalling, at which point you can accelerate up to the same top speed.
Yes. In fact Jeremy Clarkson did just this with a Corvette years ago. He started from a stop in 5th gear and sped up to the top speed north of 175mph without changing gear.
[link here](https://youtu.be/Ko9kzyqW-l8?si=UpVSofRAYxNqdjx0)
If you can get it moving without stalling, then yes. Back when I had my manual 97 Subaru legacy, i would start from higher gears for fun. It was difficult, but if I was patient and gentle, i could get it moving from 5th gear. Then once it’s moving, you can accelerate normally (though more slowly) and reach the same speed you would if you cycled through the gears.
At the expense of the clutch, sure. But it’s going to have to be slipped quite aggressively until the engine speed can sync up with travel speed.
If your scenario throws out components heating/failing (like blowing the clutch), and it’s exactly the same setup in both cars, and the transmission gear ratios are the same, then the only thing that governs top speed is friction (road and air), so I don’t see a reason they wouldn’t end up the same. It’s a lot of “ifs” though, which starts to take the teeth out of the thought experiment.
It would reach the same speed. That is if you manage to get it going to begin with. You might be able to do that by slipping on the clutch and it will not overhat or just wear out.
The diffrence wint you bike is you legs do not the same way have a minimum RPM for them to work like a internal combustion engine does. You legs has a max force, the bike have roll resistance and it multiplied by the gear ration. So you can start riding the bike at the higher gear if the force you can create is greater then the roll resistance.
Both for bike and a manual car the limited to get it going to begin with, if you can do that the max peed you can reach is the same
Yes it should. But you would end up roasting the clutch as you slowly get the tall gear up to speed without stalling the engine out.
Just like with your bicycle, it’s a lot harder to pedal from a stop in high gear. You might even have to stand up and put your weight into it just to get it moving. Now imagine a really heavy bicycle, so heavy that even with your weight it wouldn’t even move. That’s kind of what we are dealing with, and why a car wouldn’t normally be able to do so either.
The difference though is that your bike has a direct chain link between the pedals and wheels. But a manual car has a clutch disk…the clutch disk allows some slippage between the motor and the wheels. So now imagine if your very heavy bike now had a smooth rubber belt instead of a chain. When you start pedaling, at first the pedals and the belt would move, but the belt would just slip and slide around the wheel hub…but slowly the friction would slowly start to move the wheel. Eventually when the wheel and the pedals are moving at the same speed and there wouldn’t be slippage anymore. This is extremely simplified of course, but it’s the same idea.
The same engine speed in the same gear will always result in the same vehicle speed. It’s a fixed relationship. The only problem would be ruining the clutch or the engine stalling (the equivalent to the strain on your legs).
A manual transmission operates on precisely the same principles as a multi-speed bike, only the parts themselves are different.
I drive a Nissan Versa with a 1.6l 4 cyl. I routinely do stop and go moves in second gear. I don’t think it would pull enough to get moving in 5th gear. I’ve honestly never tried.
That said, I routinely skip gears depending on what I’m doing/how fast the road is. 1, 2, 3, 5 is very common. I also do 1, 2, 4 for slower speed limits.
I’m sure on a relatively flat stretch of a mile or so, with a small down hill to start out on, I could reach maximum speed while starting out in the highest gear.
Absolutely… there are times where I’ve forgotten to downshift and started up in 3rd. It doesn’t like it but it will do it
Yes, IF the engine is powerful enough to get it in motion from a stop in 5th gear. A sports car with a powerful engine and a fairly light weight could likely do this, but a regular commuter with a 4 cylinder engine would struggle and likely stall out. Also, you will burn the clutch out pretty quickly doing this.
As long as you can start the car moving, yes, it will eventually reach the same top speed.
Depending on the engine’s available torque and the gearing, it may or may not be able to set off in its highest gear. It will almost certainly involve revving the engine and slipping the clutch to some extent. This is not, in the long run, good for the clutch.
Yes. The Koenigsegg Regera has only one gear. It uses a clutch system to regulate RPM and torque from a stop.
The gears are just a direct mechanical link between wheel speed and engine speed. 7000 rpm in 6th gear is always the same speed no matter how you got there. The problem is 2mph in 6th gear would be too low of an rpm for the engine to run. You paid for all the gears you should use them.
Doing this was part of the post service checks on pre 1939 Bentleys. As was checking that an old UK penny from the same time would remain balanced on its edge at tick over.
I used to have a 2000 Audi A6 that could do it. That was only possible because it had a diesel engine with a fair amount of torque. I imagine most cars would stall if you tried to start in top gear. You also run the risk of burning out your clutch if you start in high gear too often
Yes, but you would need to rev it a lot so that the engine won’t stall and your clutch might burn. But you could.
It seems like most answers might be missing the main point of the question?
Much like an engine, you legs can only spin but so fast. You will still get to that speed no matter what.
So in any gear, your legs will get to a point where you’ve reached a point where you can’t pedal any faster. Think of your legs like an engine’s RPMs, connected to the gears of the transmission of a car. You’ll eventually get to that point in the final gear where the engine can’t (more like won’t) spin any faster. But that speed will be the same because of the ratio of the engine’s RPMs to the gearing.
Look up ‘money shifting’ at some point and that might also help put this information into perspective.
The gear you are in dictates how many rotations the wheels will make for one rotation of the engine.
So yes, it doesn’t matter HOW you got there, if your engine is at 2000 RPMs in 5th gear today, you’ll be traveling at the same speed as you were when you were at 2000 RPMs in 5th gear yesterday.
(Ignoring slippery road surfaces, wear on the tires decreasing their circumference, etc.)
What would make you think that the top speed would not be same?
It would stall out, because the gear ratio would be too hard for the engine to move from zero to thing.
Yes. You’d just have to feather the clutch A LOT and the acceleration wouldn’t be great but it can be done.
There are some cases where it couldn’t. The top gear is meant to be the most efficient so there’s actually some cars that need to be in the second highest gear to reach their top speed. Top gear will be more efficient at high speeds but may not allow high enough RPMs to get the power needed to reach and maintain top speed.
Yes you just need enough torque to get started https://youtu.be/Ko9kzyqW-l8?si=GfVn_0V9L3AWHNEU&t=97
The top speed will be the same. The gear and its ratio are the same.
Taking off initially will be difficult and possibly damaging. With your bike you can put the pedals where you want for maximum leverage. You can easily use the foot on the ground for additional help to get rolling. Failure ends with putting a foot down. The car can be forced to get moving but that’s very hard on clutches and can easily be taken to the point of causing more serious damage. Trying to take off like normal will cause the engine to stall.
The principles are the same as your bicycle .. gears are used to change effort into speed..
You could start your bicycle in the highest gear if your legs are strong enough to turn the pedals.
Cars are the same
Tested a drivetrain in my Miata that was for a race car. Had a 5speed with a short 5th and a very short rear gear 5.12. Easy to start in 3rd, if pointed downhill decent to start in 5th. A transmission is just a mathematical expression of the leverage ratios and final drive is the constant reduction. So it will always be the same. Nuances of tire slippage and parasitic loss are what make real world slightly different than paper.
Maybe. Depends on a few things:
Does it have enough output torque at the wheels to actually get rolling from a stop without stalling or destroying the clutch. If the clutch is infinitely strong/heatproof you can get around this by just slipping the clutch until you’re up to a decent speed.
Does it reach a point where it needs more power to overcome drag than it actually has at that RPM. With a fairly peaky engine, like, for an extreme example a 600cc motorcycle engine with a huge turbo.
You could get to a point where lets say you’re doing 6000rpm @ 150kph, and it’s off cam and the turbo hasn’t really spooled and it won’t break 150kph. Even though at 12000rpm it’s boosting like a madman and could crack 300kph with no problem, but without a downshift you’ll never even get on boost because you can’t push through the aero drag.
So very much “It depends”, but in the best case scenario of a engine that makes a lot of power all the way across the rev range, has a strong clutch that doesn’t mind being slipped, and a fairly low top gear ratio, then yep, your theory definitely true 🙂
10 speed freightliner approximate speeds for each gear change on flat ground
1st 2mph
2nd 4mph
3rd 6mph
4th 8mph
5th 10mph
6th 15mph
7th 25mph
8th 35mph
9th 45mph
10th 55mph
Probably maxes out at 75 in 10th.
Top speed is top speed. Doesn’t matter what gear you start in.
Bike gears are similar to truck gears in the way Legos are similar to building a house. It’s completely different, but shares some similarities.
You wouldn’t start on a hill in the hardest gear, right? And you aren’t going to bike all around the park spinning in the lowest gear, right?
A bicycle is more forgiving. The freewheeling cassette disengages the pedals from your feet, except in the case of a fixed gear bike.
A large truck you also use shifting to a lower gear to brake. Kind of like resisting the pedals on a fixed gear bike.
When I took driving lessons my instructor showed me how it was possible to drive off on level ground at 5th gear