Monday, September 19, 2011

What will happen if I had to accidently downshift from high gear into a lower gear?

What will happen if I had to accidently downshift from high gear into a lower gear?





This question applies only to vehicles with manual H-shift and manual sequential transmissions, as well as semi-automatic vehicles (e.g. Bugatti Veyron and some scooters).



NOTE: I watched Mordeth13’s video on YouTube, please check it out, just search for his channel, there’s video where he shows the viewer how to ride a motorbike and change gears. AS usual, the clutch is always used when starting up the bike. Just a safety precaution, you really wouldn’t want to start the bike without the clutch, otherwise the thing will just fly forward since it’s already engaged in gear and of course when starting a bike you got to give a little throttle to warm up the engine (and with the use of the choke lever). I ride my dad’s Suzuki GSX-R 600and I personally will NEVER change gears without the clutch, and I do not plan on doing so. But the guy Mordeth 13 clearly showed he upshifted without the clutch, but he ALWAYS downshifts using the clutch (he doesn’t know “why”, but it’s wahat he heard it can mess up the transmission). Also, he demonstrated what happens when you shift from a higher gear to a LOWER gear; the engine will attempt ot mtach the rpm of the wheel and it will immediately go to the redline. But as Mordeth demonstrated, it only locks up the rear-wheel. Don’t try this stunt, spare the wellbeing of your motorcycle – I know I do. And also it’s something I would not want to try, my bones are more important than being risked in skiing off the road. I’m just scared, heaven forbid it makes the transmission explode. Furthermore, the way I was taught by my dad: you must always use the clutch because it’s the mechanism used to change gears smoothly once the rpm of the engine matches that of the wheels. In other words, you ride the gear up ot its maximum design speed (just below the redline on your tachometer) and change to the next gear, thereby matching the rpm that starts for that gear. Notice what happens when you try changing gears, without the clutch and WHILE YOU GOT THE THROTTLE ON, the engine will immediately rev way up to the redline (during the gear change interval) and it will shut down or stall.



So with all this in mind, my questions are as followss:

1. What will happen if you were to downshift from high gear to a much lower gear?

2. Are there any safety mechanisms in place to prevent a redline as a result of having too much rpm for a specific gear?

3. Are there any negative effects of shfiting too early to a lower gear, so as to create engine braking?

4. What will actually happen if I had to accidently downshift from high gear into a lower gear? Say, as in downshifting from high-speed in Gear 6 right down to Gear 1. :-|



Thanks!

Sorry for the long details, and I appreciate your answers...What will happen if I had to accidently downshift from high gear into a lower gear?1. You may not be able to. The baulk rings in the gear box stop the gears shifting if there is a large disparity in speeds.

2. No, there are no safety mechanisms in most vehicles. Damage can and often does result. That is why some vehicles have tachometers.

3. Using the gearbox too much wears the gearbox.

4. Nothing wrong with downshifting so long as the engine is kept within the safe range.



Down shifting and up shifting is a normal part of operating vehicles. With certain types of gearboxes, it is quite easy. The engine RPM is adjusted to match the ratio of the gearbox. The process is known as double-declutching when the clutch is used but it can be done without it as the procedure is the same. The gears must be at the same rate for this to be practical. It requires skill.What will happen if I had to accidently downshift from high gear into a lower gear?You will set your RPM's up drastically high, to the point where you could blow your engine or a gasket out -- Blessings !What will happen if I had to accidently downshift from high gear into a lower gear?If you did that it would most likely burn out your engine because it would redline soo hard. On an automatic it just keeps it in nuetral but on a manual I dont think theres any saftey measures. The mythbusters tried something like this once they were testing a myth that throwing the car into reverse would slow the car faster than breaking but they couldnt get the wheels spinning backwards.