[rohan_cherian]

Hi.
Have a couple of questions I need to get resolved.
1. Picture this:
Spot a speed bump, feather the brakes, clutch, downshift and ease out into the lower gear while still feathering the brakes and then ride the clutch over the bump to ease the jolt. The rev jump isn't negligible but isn't violent either, that's why I use the brakes in tandem.

Is there a fault in my technique? Also, can't really figure out when to rev match and how.

2. When I ease out into the lower gear, my brake pedal goes down a bit. Not limp, but almost like a phantom force was pressing down on it.
Bounces right back after that. Is this normal?

I'm a novice so it would be great if you could keep the jargon to a minimum. Thanks.

This is on an '05 Esteem VXi.

[jinojohnt]

Is there a 'machine' that is capable of testing how efficiently a driver uses the clutch/gear/brakes? Rather than relying on 'hear say', is it possible to 'measure' this?

[rohan_cherian]

Originally Posted by jinojohnt

Is there a 'machine' that is capable of testing how efficiently a driver uses the clutch/gear/brakes? Rather than relying on 'hear say', is it possible to 'measure' this?

Formula One teams use advanced telemetry to measure driver inputs at all times. Clutch/gear/brakes are just a tiny subset of the data monitored.

They then analyze the graphical data and tailor their driving style accordingly.

[a4anurag]

Originally Posted by jinojohnt

Is there a 'machine' that is capable of testing how efficiently a driver uses the clutch/gear/brakes? Rather than relying on 'hear say', is it possible to 'measure' this?

Life of the parts will give your answer.

With regular usage of the car, if the parts survive for longer duration (kms I mean) then you are driving 'right'!

Getting instantaneous results AFAIK is difficult for a regular Joe.

[me_sid]

Originally Posted by rohan_cherian

Hi.
Have a couple of questions I need to get resolved.
1. Picture this:
Spot a speed bump, feather the brakes, clutch, downshift and ease out into the lower gear while still feathering the brakes and then ride the clutch over the bump to ease the jolt. The rev jump isn't negligible but isn't violent either, that's why I use the brakes in tandem.

Is there a fault in my technique? Also, can't really figure out when to rev match and how.

2. When I ease out into the lower gear, my brake pedal goes down a bit. Not limp, but almost like a phantom force was pressing down on it.
Bounces right back after that. Is this normal?

I'm a novice so it would be great if you could keep the jargon to a minimum. Thanks.

This is on an '05 Esteem VXi.

Hi Rohan,

In my opinion couple of things that we should take into account before we cross a speed breaker, we need to free the suspension to travel full before we hit the speed breaker. Means, when we brake the entire weight is shifted to the front, and the suspension gets compressed. The braking needs to be done way prior, so that you are at your desired speed before you hit the speed breaker, and your front suspension is free to travel the full. And yes no clutch please, don't ride on the clutch, you don't smoothen anything, by clutching you disconnect the engine and transmission. So effectively you are reducing the speed (due to friction). I would suggest depending on the size of the bump/hump, lower your speed, since its an esteem, most of them would require you to go down to the 1st. Come to a stop slot in 1st no clutch no gas, cross the speed breaker and upshift normally.

Rev match is when you need to slow down without braking. Blip the throttle to a level of 1k more if you are downshifting 1 cog or 2k if its 2 cogs ( thumb rule varies from car to car) and then simultaneously shift down and release the clutch. There are innumerable videos in Youtube to check the right technique.

Regards
Sid

[a4anurag]

Originally Posted by rohan_cherian

I'm a novice so it would be great if you could keep the jargon to a minimum. Thanks.

This is on an '05 Esteem VXi.

I presume that you know there is a speed breaker and you are approaching it normally.

So what you must do is use the engine braking by downshifting (5-4-3-2-1) with proper intervals to avoid 'over-revving', once you reach 10-15 kmph use the brakes to control the speed before approaching the speed breaker.

Once you are near it, release the brakes shift to 1st or 2nd gear and press the accelerator slowly so as to ease the load on the springs.

Once you brake, the weight transfer happens causing the front end to become heavy with the spring compression causing lesser travel of suspension when going over the hump. Once you have braked in advance and shift in gear with mild accelerator input, the front end does get light with more travel aided to the suspension to complete the speed breaker smoothly.

This should solve your issue.

[rohan_cherian]

Originally Posted by me_sid

Hi Rohan,

In my opinion couple of things that we should take into account before we cross a speed breaker, we need to free the suspension to travel full before we hit the speed breaker. Means, when we brake the entire weight is shifted to the front, and the suspension gets compressed. The braking needs to be done way prior, so that you are at your desired speed before you hit the speed breaker, and your front suspension is free to travel the full. And yes no clutch please, don't ride on the clutch, you don't smoothen anything, by clutching you disconnect the engine and transmission. So effectively you are reducing the speed (due to friction). I would suggest depending on the size of the bump/hump, lower your speed, since its an esteem, most of them would require you to go down to the 1st. Come to a stop slot in 1st no clutch no gas, cross the speed breaker and upshift normally.

Rev match is when you need to slow down without braking. Blip the throttle to a level of 1k more if you are downshifting 1 cog or 2k if its 2 cogs ( thumb rule varies from car to car) and then simultaneously shift down and release the clutch. There are innumerable videos in Youtube to check the right technique.

Regards
Sid

Hey Sid,
Thanks for the insight about the suspension travel, I had no clue and I'll surely keep it in mind.
Although my objective here was to use engine braking in tandem with the brakes.

Correct me if I'm wrong but using the clutch while going over a speed bump or a pothole does make a palpable difference by reducing the kickback to the transmission/drivetrain. Like I stressed earlier, please do correct me if I'm wrong.

Originally Posted by a4anurag

I presume that you know there is a speed breaker and you are approaching it normally.

So what you must do is use the engine braking by downshifting (5-4-3-2-1) with proper intervals to avoid 'over-revving', once you reach 10-15 kmph use the brakes to control the speed before approaching the speed breaker.

Once you are near it, release the brakes shift to 1st or 2nd gear and press the accelerator slowly so as to ease the load on the springs.

Once you brake, the weight transfer happens causing the front end to become heavy with the spring compression causing lesser travel of suspension when going over the hump. Once you have braked in advance and shift in gear with mild accelerator input, the front end does get light with more travel aided to the suspension to complete the speed breaker smoothly.

This should solve your issue.

Hey Anurag,
Thanks for the insight, I'll keep these tips in mind the next time. Although I have a lot to learn in terms of rev-matching.
Also, I was hoping to find some answers as to why I experience phantom braking when I ease out the clutch into a lower gear.

I know of no mechanical linkages between the transmission and the braking and it simply baffles as to how the pedal goes a little limp under my foot only to bounce back a moment later.

[SyncNest]

my dad uses the clutch a lot. near the signal stops he keeps it depressed, both clutch and brake, doesnt use the hand brake- says it confuses him when he has to start the car back up once it is green

maybe thats y we had to replace the clutch plates on our alto at just 27k odo reading

[Grand Drive]

Originally Posted by a4anurag

So what you must do is use the engine braking by downshifting (5-4-3-2-1) with proper intervals to avoid 'over-revving', once you reach 10-15 kmph use the brakes to control the speed before approaching the speed breaker

In Bangalore, most of the speed breakers are not even and also very high. If I know the speed breaker presence in advance, prepare to downshift to 2nd gear while climbing up and as the speed reduces during climb up, now downshift to 1 and climb down. When I try these humps in 1st gear, not enough power to climb up and thereby engine getting stalled. Is this right ?

In smoother and properly constructed humps, I can smoothly go in 2nd gear without any fuss.

near the signal stops he keeps it depressed

If not in gear at signal, sometimes it rolls back. So stopping at the signal with first gear. Do I need to come to neutral and engage the parking brake ? Most of the times, in the peak rush hour traffic, people are getting impatient and keep on honking in the moment signal turns green, I try to pull down the parking brake lever, clutch and first gear. What needs to be done in signals with No Timers ?

[mazda4life]

Next to the Lathangi Ford service center in Bannerghatta road, I see this duster always parked with the front wheels on the flat surface of the road and rear wheels on the inclined ramp ( see pic) . My question to members is that , is such parking advisable ?, will there be any significant stress on the vehicle due to such a parking practice?

[a4anurag]

Originally Posted by mazda4life

Next to the Lathangi Ford service center in Bannerghatta road, I see this duster always parked with the front wheels on the flat surface of the road and rear wheels on the inclined ramp ( see pic) . My question to members is that , is such parking advisable ?, will there be any significant stress on the vehicle due to such a parking practice?

Suspension and Handbrakes would be under load always to keep the vehicle in place.

[BertieWoosert]

I just wanted to check if there is a correct technique for slowing down on highways for speed-breakers. I did the Mumbai-Dhule-Mumbai (NH3) recently, which has a number of speed-breakers at junctions or just before villages.

When you are driving at around 100-120 kmph in fifth gear, and you spot a speed-breaker from ~100 m, is there any other "correct" way to slow down - other than start braking as soon as you spot a sign, and slow down enough so that you can slot to second (or first if needed) gear at the speed-breaker? Does it cause any extra pressure on the brakes if you frequently slow down from fifth gear to second directly without going through the intermediate gears?

A final question out of curiosity - does anyone know why there are almost 15-20 of those rumble strips together, when 3-4 should do the same job? I found these quite painful to navigate - any tips for handling them better?

[KiloAlpha]

Originally Posted by BertieWoosert

I just wanted to check if there is a correct technique for slowing down on highways for speed-breakers. I did the Mumbai-Dhule-Mumbai (NH3) recently, which has a number of speed-breakers at junctions or just before villages.

When you are driving at around 100-120 kmph in fifth gear, and you spot a speed-breaker from ~100 m, is there any other "correct" way to slow down - other than start braking as soon as you spot a sign, and slow down enough so that you can slot to second (or first if needed) gear at the speed-breaker? Does it cause any extra pressure on the brakes if you frequently slow down from fifth gear to second directly without going through the intermediate gears?

A final question out of curiosity - does anyone know why there are almost 15-20 of those rumble strips together, when 3-4 should do the same job? I found these quite painful to navigate - any tips for handling them better?

I don't know about any "correct way", but there are 2 ways I handle slowing down - depending on whether I have my family with me or not
If with family, I will first let off the A-pedal, shift down 5-4-3, and then start braking.
If without family, clear road ahead and no traffic behind and clear visibility of the speed breaker, I will do F1 style max braking in last minute.

As far as rumble strips are concerned - the wrong way of taking them is to go slowly over them at crawling speed. That increases the pitching-and-bobbing of the car and makes things very uncomfortable. Depending on the height of each rumble strip, their spacing, and your car's suspension set up, there is an ideal speed to take them where your car "skips" over each strip. Despite the horrible suspension noise, it is actually the most comfortable. I have learned this with experience. I went over every set of rumble strips with this technique, my Figo did not develop squeaks/rattles in the long term.

[jkrishnakj]

What i do is, to continue at the same speeds, gradually lowering the pressure to pedal A, and when i am about to reach the speed breakers, its the full clutch press, with brakes pressed, and doing the 5/4/3 to cross it, or 2nd gear if it warrants.

On rumblers, i used to clear them off without doing anything, so long as the roads are clear and i see no obstacles or i see nothing untoward running into my path. This was true so long as i had my Safari. Now, with my Innova, i do slow down and take the rumblers with a lot more love. Agree with KiloAlpha here. It is a pain to cross the rumblers in very slow speeds. Its quite irritating for me atleast.

[SmartCat]

Heavy buses and trucks would have squished a small section of those rumble strips. So, in your car, you approach the rumble strip in such a way that one side of wheels are on the squished section. You will have a much smoother/faster ride over the rumblers!