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Old 30th April 2014, 08:45   #31
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Default Re: Highway fuel economy less than in the city - Why?

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Originally Posted by EcoBeast View Post
why would the clutch have wear and tear while rotating freely in neutral?
To shift to neutral and to another gear you need to use clutch twice, right? Instead, let the transmission do its duty and eventhough if you feather the accelerator to keep the momentum, engine load will be ~25-35% (depends on the gear and rpm).

Last edited by ::CMS:: : 30th April 2014 at 08:49.
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Old 30th April 2014, 09:10   #32
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Quote:
Originally Posted by EcoBeast View Post
why would the clutch have wear and tear while rotating freely in neutral?
To each change to 'neutral' from the gear that is being used the clutch needs to be (pressed and released) - 1st time.

Then to get onto the required gear the clutch needs to be (pressed and released) - 2nd time.

The first gear change set will not be that harmful as theRPM of theengine willdrop from 'X' RPM to idle RPM within seconds.

But the second one is where the car speed + engine RPM needs to match with the 'right' gear and to do that without jerking is a bit difficult. That jerk will be grinding the clutch and it's other parts leading to greater wear and tear.

I have seen drivers hold the clutch pressed and forcefully shift to the required gear and hold the clutch pressed. When needed they release it fast and at a go without trying to match the revs for a smooth shift. This causes load on the transmission to damage if done regularly.

Hooe this helps!

Quote:
Originally Posted by ::CMS:: View Post
To shift to neutral and to another gear you need to use clutch twice, right?
+1.

PS: Sorry MODS for going OT!

Anurag.
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Old 30th April 2014, 13:53   #33
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Default Re: Highway fuel economy less than in the city - Why?

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Originally Posted by a4anurag View Post

But the second one is where the car speed + engine RPM needs to match with the 'right' gear and to do that without jerking is a bit difficult. That jerk will be grinding the clutch and it's other parts leading to greater wear and tear.

I have seen drivers hold the clutch pressed and forcefully shift to the required gear and hold the clutch pressed. When needed they release it fast and at a go without trying to match the revs for a smooth shift. This causes load on the transmission to damage if done regularly.

Hooe this helps!

Anurag.
Yep. That's make perfect sense. That is exactly how I believed it works.
The point here is that, it's not the neutral driving that causes load on the engine. The real culprit is 'an improper step-2' which, if executed correctly, will not hurt the clutch plates & pads that much.

I thought the OBD data collected by CMS showed that the engine was under load WHILE in neutral. Which didn't seem to add up.
I think we are all on the same page now.

Thanks for the clarification.
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Old 30th May 2014, 18:08   #34
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Default Re: Highway fuel economy less than in the city - Why?

Dear All,

Thanks a lot for the inputs!

Sorry, I was not able to reply in time, since I was banned for few days.

Would like to update that, my issue is now resolved, and I am able to get 22 km/l on highways.
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Old 30th May 2014, 18:41   #35
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Default Re: Highway fuel economy less than in the city - Why?

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Would like to update that, my issue is now resolved, and I am able to get 22 km/l on highways.
Good that the FE is back on track. May we all know how was the issue solved and how are you now achieving 22 kmpl?

Anurag.
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Old 30th May 2014, 19:59   #36
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Default Re: Highway fuel economy less than in the city - Why?

Mod Note : Post deleted.

Team-BHP strongly discourages unsafe driving practices that put yourself and other road users at risk. Please do NOT post about illegally high speeds on public roads.

We advise you to read the Forum Rules before proceeding any further.

Last edited by GTO : 31st May 2014 at 18:23.
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