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Old 29th January 2007, 20:06   #46
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Question High Revs coming downhill.

Hi folks,

First of all I must admit that I am not an expert at hill driving, so I am looking for inputs from experienced Bhpians.

Today I took my almost 9-month old WagonR to the steeper hills for the first time really (The previous runs were the not-so-steep ones). It a short, but steep climb. The uphill climb was very good, with me and a friend riding.

Now when coming downhill, the short stretches of steep road went fine - I had to apply brakes, especially at the turns. I was careful not to ride the brakes or the clutch.

Now there was this particularly long straight strip of road heading downhill. I was going at gear 2, not braking much - the car was really revving at 3100. Also, it started speeding up to 40 kmph, much to my discomfiture. I was hardly putting any pressure on the accelerator. Things normalized once were hit level ground.

Please tell me if this is normal? I have taken my old Santro before on hilly strips (perhaps not as steep), but I don't think it revved so much (did not have an Odo on that one).

The other thing I noticed was that the fuel gauge seemed to have dipped a few degrees all off a sudden. I had a full tank when we set off in the morning. The fuel gauze normalized (went up) once we were in the plains...is that due to the incline of the car?


Thanks in advance.

Johy

Last edited by johy : 29th January 2007 at 20:10. Reason: Re: Added question on fuel gauge.
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Old 30th January 2007, 07:49   #47
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This is quite normal....
Fuel guaze thing is normal due to inclination...

It is normal as well to see the revv go up at lower gears while descending steep incline...you need to control the engine braking with your brakes to keep at a decent speed...
Had you driven in a higher gear, you feel a higher speed and lower revv but very difficult to control the car (u will feel that the car is flying off)...and ofcourse load on the brakes...
Abhi
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Old 30th January 2007, 10:50   #48
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Dear akroy,

Thanks for your response.

Yes, the engine braking helped a lot on that steep incline, but I think I could have used the brakes a little more that I did yesterday. I am sometimes paranoid about burning my brakes!

Johy
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Old 30th January 2007, 12:07   #49
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if you are planning ur trip on a diesel vehicle

1) Fill some diesel from one of the high range diesel bunks, coz they add some sort of chemical in diesel which would prevent the diesel from getting solid.

2) Give way to up coming traffiic always specially buses and lorries...
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Old 27th December 2007, 19:21   #50
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Quote:
Originally Posted by rks View Post
Another possibility is that on some bends, the heavy vehicle would have to make a very sharp turn with very small turning radius, if it were to keep left. So maybe on such bends, it would be easier for the heavy vehicle to make a larger turn by keeping right and let the smaller vehicle make the tight turn.
Not all the bends will have a tight turning radius which force the heavy vehicle to keep extreme right to gain enough T.radius.

How will one judge [esp the oncoming(downhill) smaller vehicle] such bends



Quote:
Originally Posted by rks View Post
Sometimes, however, smaller vehicles make the mistake of not stopping in advance and get too close to heavy vehicles coming on the opposite direction on narrow bends. In such cases, the only way out (if the reversing option is not available) may be for the smaller vehicle to move to its right and make way for the larger vehicle.
Regards, rks
I did caught in this situation earlier. But there was enough gap for me to cut into the left hand side of the heavy vehicle. Driver of the vehicle was very upset as I forced him slow down heavily and was shouting at me.


I felt like it was not my mistake as I was keeping left and no way I could predict such situations.

Never come across such situation again.
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Old 27th December 2007, 20:02   #51
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Quote:
Originally Posted by Surprise View Post
Not all the bends will have a tight turning radius which force the heavy vehicle to keep extreme right to gain enough T.radius.

How will one judge [esp the oncoming(downhill) smaller vehicle] such bends
Well, I guess you have to observe the body language of the heavy vehicle and react accordingly. He may flash his lights at you and/or honk, indicating his intention to stick to his right. You should try to look as far ahead as possible on narrow hill roads and try to anticipate such situations to the extent possible.

Quote:
I did caught in this situation earlier. But there was enough gap for me to cut into the left hand side of the heavy vehicle. Driver of the vehicle was very upset as I forced him slow down heavily and was shouting at me.

I felt like it was not my mistake as I was keeping left and no way I could predict such situations.
As far as possible the heavy vehicle should be given right of way without having to slow down while going uphill. Otherwise it can get very difficult for the driver, especially if the vehicle is loaded. That is why he probably got upset.
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Old 16th May 2008, 12:07   #52
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Question How to Drive in Hilly Regions

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

In almost all parts of the country, we come across terrains with mountain/hilly regions. People commute in these regions on a daily basis or periodically, depending on their needs. Driving a car uphill or downhill requires skills.

The purpose of this thread is to discuss the various techniques that can be used while maneuvering curves in hilly regions (uphill or downhill), so that people reach their destinations safely.

This is what happened with me:
I and 5 of my friends had been to Ooty in my Maruti Esteem. We took the Mysore-Bandipur-Kalatti Ghat-Ooty route (Kalatti Ghat is a part of the Western Ghats with 36 precarious hairpin bends). Reaching Ooty was no problem; no issues at all. On the way back, I was at the wheel (I had a driving experience of around 4-5 years then). The car was kind of weighed down, since there were 6 people in it, all well built.

While coming down Kalatti ghats, I had to use the brake frequently; shifting into lower gears was not helping much because of the car weight. Also, when in lower gears (2nd & 3rd), the engine used to scream like hell (I didn’t like that) as the car was speeding because of the steep descend. So, I used the 3rd and 4th gears with more than normal usage of the brake, which was inevitable.

Everything was fine, and I made the last hair-pin turn (the 36th), and people who have the knowledge of this route will know, there is a long straight downhill stretch after the 36th hair-pin bend. I was in the 4th gear I think, and the car was gaining speed. In order to slow down I pressed the brake pedal and the pedal went in straight and touched the floor like a clutch!

I didn’t tell anyone, shifted to lower gears (2nd and then 1st), used the handbrake (which was least effective), and somehow managed to slow down the car on the flat terrain after descend. Then told everyone what had happened, got out of the car and inspected the front wheels. They were piping hot and smoking!

Understood that the brake pads had heated up due to excessive use and were in a semi-solid kind of state. Putting water would cause the pads to crack. Waited there for about 90 mins. Slowly got back the stiffness in the brakes. It was already getting dark. Started moving slowly and used only the lower gears and handbrake for rest of the journey. By the time we reached Mysore the brakes were almost back to normal. Was thinking what would have happened if the brakes had failed somewhere in the middle of the descend!

Next day went to Mandovi Motors and got the brakes checked. They were perfectly fine! No sign of anything whatsoever. Only the wheel discs had gone black.

My questions are:
1) Did I do any mistakes while driving downhill? Should I have downshifted to 2nd gear?
2) While descending a steep hill/mountain, do the clutch plates get damaged due to downshifting?

Hope that you all will share your experience if any and give some driving tips, so that it would help all in such situations.

Last edited by Rehaan : 19th May 2008 at 07:27. Reason: Please see note in post.
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Old 16th May 2008, 12:45   #53
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The thumb rule that really works well while coming downhill is the following

While coming downhill, you should be in the same gear as you would be if you were going uphill on that road.

Quote:
Also, when in lower gears (2nd & 3rd), the engine used to scream like hell (I didn’t like that)
The engine was screaming like hell because you were coming down too fast. 2nd gear is a good one for Kalahatti ghat.
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Old 16th May 2008, 13:50   #54
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I can't say I have a lot of experience of driving in hilly regions. But this is what I follow. Breaking is all about converting kinetic energy of the car into heat energy. So I don't let the car gather too much speed in the first place by using the breaks intermittently. In case the engine appears to rev a lot 2nd gear I dab the breaks a little more than required periodically instead of pressing continuosly.

The clutch won't be affected by downshifting. But the engine life will be shortened a bit because of the high revs.
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Old 16th May 2008, 13:57   #55
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Quote:
Originally Posted by Dolphin View Post
My questions are:
1) Did I do any mistakes while driving downhill? Should I have downshifted to 2nd gear?
2) While descending a steep hill/mountain, do the clutch plates get damaged due to downshifting?
.
The mistake you made is a very common mistake made by ppl not used to driving in the hills ... As Hondadude mentioned that the staple formula is that one should be in the same gear downhill in which he went uphill , its true but what hondadude hasn't mentioned is how would someone know the answer to that if he hasn't gone uphill on that particular stretch ever ??

The mistake you made is that you were in a MUCH higher gear than what you should have been in . Higher the gear - more the momentum thus leading to heavier braking when needed . I have no idea how steep that stretch is or how many corners it has but you should have stuck to 1st - 2nd even if the engine was screaming . The engine acts as a break as well so when you need to tap the brakes , a lesser pressure would make it slow do down for the corner . Once you feel the engine scream too much just tap the brakes a bit and it will be all fine .

The second question -- Didn't understand it so could you be a bit more specific ???

Cheers
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Old 16th May 2008, 14:09   #56
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Thanks Khaadu75 and HondaDude,

Am planning to drive to ooty in couple of weeks time and had these questions in mind. Thanks for solving them in advance
@Khaadu75,
Guess his second question was to ask if the clutch plates get damaged if you down shift gears while descending the hill(May be he wants to clarify if one down shifts at a relatively higher speed compared to that gear range. Am guessing this as he mentioned the engine was screaming during the down shifts)
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Old 16th May 2008, 14:28   #57
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Quote:
2) While descending a steep hill/mountain, do the clutch plates get damaged due to downshifting?
As long as you don't try to slip the clutch there should be no [extra] damage.
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Old 16th May 2008, 14:37   #58
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Quote:
Originally Posted by khaadu75 View Post

I have no idea how steep that stretch is or how many corners it has but you should have stuck to 1st - 2nd even if the engine was screaming . The engine acts as a break as well so when you need to tap the brakes , a lesser pressure would make it slow do down for the corner . Once you feel the engine scream too much just tap the brakes a bit and it will be all fine .

The second question -- Didn't understand it so could you be a bit more specific ???

Cheers
The terrain is indeed very steep.

While descending, you have mentioned to stick to 1st and 2nd gears even if the engine is screaming. Here is exactly what I want to know. Does this damage the clutch plates? Because I remember some mechanic or a friend of mine saying that downshifts at a relatively high speed affect/damage the clutchplates of the car or even melt them!
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Old 16th May 2008, 14:55   #59
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another thing is that you need to develop a feel for the brakes.

They don't go suddenly. Fade starts, and then hits badly.

When you notice fade, stop/slow down or change your driving style.
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Old 16th May 2008, 15:02   #60
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Quote:
Originally Posted by Dolphin View Post
Everything was fine, and I made the last hair-pin turn (the 36th), and people who have the knowledge of this route will know, there is a long straight downhill stretch after the 36th hair-pin bend. I was in the 4th gear I think, and the car was gaining speed. In order to slow down I pressed the brake pedal and the pedal went in straight and touched the floor like a clutch!
Its really scary . Good to hear that you managed it well. I have never even thought of these situations. Thanks for bringing it in the forum. it would certainly help a lot others.
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