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Old 8th January 2005, 13:50   #91
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Too many points! Do you guys ever meet up in person, or is this the only mode of communication?

Am asking, coz would be nice to yakk about this face to face so all clarifications / issues can be resolved (if not globally, at least amongst us ).
I suggest you take a look at this.

Team bhp meet thread (Team BHP Meet Thread)

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Old 20th June 2007, 21:58   #92
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Sorry for bumping up this oldy. but man what a discussion.

Ok now the reason for bumping this up. Say your in second gear and your braking. You come to a speed in which the second gear will not pull the car. So you down shift but your too fast for first and it doesnt slot in.

I'm guessing this is because the speed of the input shaft of the gearbox is lower since the rpm in second gear is not much whereas the output shaft to the wheels is spinning faster as the car's speed is higher for first gear.

Sometimes this can be a pain. Aren't the synchros supposed to help match the speeds so one doesnt have to double clutch?

Is there any other workaround to make this a smooth shift. Revv matching is kinda difficult in the case you are approaching a speed breaker. Also rev matching for the first gear very occasionally results in a jerk.

Do we have no other choice but double clutch?
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Old 26th June 2007, 10:58   #93
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Default Changing gears - H or reverse N?

I wanted to ask if when changing from 2nd to 3rd if you use

- an "H" pattern (go straight up, straigt right, and then up again)

or

- a reverse "N" pattern (go diagonally upwards to the right from 2nd to 3rd).

I was wondering if gearboxes are designed for a straight H pattern and if shifting diagonally upwards is taking a shortcut which will have a bad effect on the gears?

This is the same as for shifting from 4th to 5th, vice versa, and back from 3rd to 2nd. So it doesn't have to do with going to neutral first, just the proper direction of movement of the gear lever.
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Old 26th June 2007, 11:01   #94
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Best way to change from 2-3 is to guide the gear lever to Nuetral and then push it up to gear 3. For best results consider this 2 step approach.
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Old 26th June 2007, 11:10   #95
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I throw to neutral (diagonal up right) and then straight up. This is the correct way I think. First to neutral and then to third. The entire 2 step is done in one stroke.
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Old 26th June 2007, 15:07   #96
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@Tsk1979, what you've described is the H pattern.

@caliper The H pattern is desirable, and it need not be done via 2 separate strokes. It can be done in one stroke. If you use the diagonal approach, the gear lever bush would be subject to higher wear and tear and result in free play after couple of months.

Last edited by risga : 26th June 2007 at 15:11.
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Old 27th June 2007, 13:01   #97
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Originally Posted by risga View Post

@caliper The H pattern is desirable, and it need not be done via 2 separate strokes. It can be done in one stroke. If you use the diagonal approach, the gear lever bush would be subject to higher wear and tear and result in free play after couple of months.
OK, thanks for the tip. My driving instructor had wanted me to go for a straight diagonal pattern, but I didn't feel that that's what the gearbox wanted.

Rather it seemed like I would be cutting a corner, and something or another would be getting worn off.

I think, though, that most drivers (of taxis) do the reverse "N".
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Old 4th July 2007, 00:27   #98
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Default RIght way to shift gears?

Note from Mod - Threads merged. Please use the search feature before creating new threads. Thanks

Hi Team,

I have this habit of shifting from 4th directly to 2nd gear when driving in the city or when I have to slow down a little abruptly.

But I remember reading elsewhere that gears should not be shifted like that.. but should come down in sequence..

Well now I just control myself and ensure I touch 3rd and then come to 2nd..

Can anyone ratify this?? If it is wrong to shift like that.. what would be the technical reason for the same...

Thanks in advance..
Nimz

Last edited by Rehaan : 4th July 2007 at 23:16.
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Old 4th July 2007, 00:51   #99
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Well as far shifting of gears is concerned, while going up you should maintain the sequence i.e 1 - 5, but while shifting down its okey to change from 4 to 2 or 5 -3 or any other sequence.
This is what i was told by one of the service guy at maruti.
Gurus correct me if am wrong..
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Old 4th July 2007, 01:14   #100
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Well with Synchromeshing you can technically shift any gear to any gear provided the engine rpm corresponding to the "shifting to" gear isn't on the extreme side for the speed the car is travelling.

Say you are at 140 on 4th , you cannot come down to 2nd just like that. It all depends on how the ratio's are stacked up and what are the speed ranges for the rpm range the engine offers.
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Old 4th July 2007, 02:30   #101
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Quote:
Originally Posted by Nimz View Post
Hi Team,

I have this habit of shifting from 4th directly to 2nd gear when driving in the city or when I have to slow down a little abruptly.

But I remember reading elsewhere that gears should not be shifted like that.. but should come down in sequence..

Well now I just control myself and ensure I touch 3rd and then come to 2nd..

Can anyone ratify this?? If it is wrong to shift like that.. what would be the technical reason for the same...

Thanks in advance..
Nimz
I suppose it is acceptable downshifting from 4th gear to 2nd if your speed demands it. I have done it a lot of times on my Esteem and have never had anything go wrong so far. When you are in a hurry to slow down, you obviously do not have enough time to shift from 4 to 3 and then from 3 to 2. In a car, unlike a bike, once you shift into neutral you are free to choose any gear as per the speed at that point of time.
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Old 4th July 2007, 03:01   #102
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Since the forward gears are all synchromesh one can move from any gear to any gear. But the key to this is not to strain the engine in case you are travelling to a higher gear. Say changing from 1st to 3rd at very low RPM's will only cause excessive stress on the engine and cause it to subsequently knock, judder and engine may die out.

Similarly, shifting down to a lower gear care should be taken not to strain the engine again. Say you are redlining in 4th and for some reason you have to shift to 2nd immediately. This will only cause the engine revvs to bounce of the revv limiter since the engine will now have to match the revvs in that particular gear. Hence once again causing additional stress on the engine since at these high revvs there might not be fuel supply to the engine if and should the revv limiter cut off fuel supply. Which is again harmful to the engine.

As long as the shifting is done within safe limits there should not be a problem.
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Old 4th July 2007, 03:47   #103
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what are powershifts?
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Old 4th July 2007, 12:10   #104
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Hi Team,

I have this habit of shifting from 4th directly to 2nd gear when driving in the city or when I have to slow down a little abruptly.

But I remember reading elsewhere that gears should not be shifted like that.. but should come down in sequence..

Well now I just control myself and ensure I touch 3rd and then come to 2nd..

Can anyone ratify this?? If it is wrong to shift like that.. what would be the technical reason for the same...
It's ok to downshift to any gear that allows the engine to revv below it's redline at that given vehicle speed.

But if you're into performance driving, it's a good habit to go down in a sequence. This keeps the revs in the powerband, provides better engine braking and makes for safer/smoother downshifts.

Shan2nu

Last edited by Shan2nu : 4th July 2007 at 12:13.
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Old 4th July 2007, 12:20   #105
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Well i change according to speed though most of the time its 3rd gear even at less than 20KMPH.. Though the worst habit i have is if i see that road is clear i shift 1st > 3rd > 5th lol... (the reason behind FE lol) and if there is a great amount of traffic on road and i know i cant go beyond 40 kmph i slot the 4th and keep on driving.

I hope my habit of skipping gears while up shifting is not too much of a concern ??
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