[Manuuj]

Originally Posted by Marauder

Hi Manuuj, sorry if you've mentioned it in earlier posts but could you share the location of the place from where you've got these custom mats?

The area is called Abdul Aziz Road in Karol Bagh. The shop isn't prominent and is loacted up 4 or 5 stairs from the main road somewhere next to a shop called Crystal Car Care. There is a guy who sits with a stitching machine and can be seen from the main road. His shop did not have a name.
Another famous shop almost next to it is called Auto Music Emporium.
Sorry i couldn't be of more help.

[ringoism]

Originally Posted by Poitive

Yes, science indeed is an interesting subject, even though I studied it way back and have quite lost touch. In case you are interested in science, please check up more on Rotational Inertia. Further smaller issues would be Unsprung Mass vs Sprung Mass.

As you clarified further on, unsprung mass has to do with suspension dynamics, nothing at all with FE.

Rotational inertia is granted a potential factor, but again as noted, only if in a prominent state of repeated acceleration/ deceleration.If highway mileage is similarly suffering, this suggestion goes out the window.

One thing I'm not sure anyone has asked is whether the toe-in setting could be significantly off vs. other alignment specs, that one can create a massive amount of additional friction/ drag.

5.6kmpl (where double that would seem more normal) just seems inexplicable in terms of 12kg's additional inertial mass (after all it represents a very small load on the engine vs. the inertial load represented by the vehicle's total mass), or even tread design / rolling resistance, unless someone was running something a LOT wider/ more aggressive than stock. A few % difference in circumference will create an equivalent error.

What we really need is to get Sutripta in on this one :-) !!

Sorry for any unpoliteness, sometimes I react a bit to what seem to be highly confident assertions on shaky/ incomplete bases.

We all have lots to learn in some realm or the other.



-Eric

[digitalnirvana]

Hi Manuuj I'm concerned seeing the logo installed on the steering. Is it safe, considering there is an airbag in there? Please remove it or cross check with Force Motors - perhaps it is safe and I'm over thinking.

[Poitive]

Originally Posted by Manuuj

The steering and back logo also got completed today with the ring around it. Chose to go with the same silver color for the ring as the Khukri was in.

The ring makes all the difference and really does make the logo look complete. Neat!

~~~~~~~~~~

Have quoted the relevant parts in a series of quotes to make it easier to follow the discussion. Some highlights/formatting in the following quotes done me.

Originally Posted by Manuuj

I will update the FE figures soon. I feel though that i am not getting over 9 kmpl in city driving at the moment.

Originally Posted by Manuuj

I was thinking about my Fuel Efficiency figures today. I could not imagine why i wasn't getting atleast 10 kmpl within the city.
....
- So basically for every 155 km I've actually travelled it only showing as 150 kilometers traveled. Therefore when i divide the Number of Kilometers travelled by Fuel Quantity used i am actually dividing by a lower number of kilometers than i have actually travelled. This in turn gives me a lower FE figure.

The error in the attachments in the above post noted a difference of 3.4%

Originally Posted by Poitive

Manuuj bro, besides the circumference causing an odometer error, the bigger factor at play is likely to be the following. Please check and consider:
1. Increased weight of the alloys (?)
2. Increased weight of the tyre.
3. Tyre tread and compound.

Increased weight of the rim and tyre makes a significant difference to FE. It is not the same as carrying as much weight inside the cabin. The weight of the wheels is a direct load on the engine system, unlike the carried weight on something that is on wheels.

Tread and compounds have a lot of impact on rolling resistance; again something similar in effect to the direct weight mentioned above.I believe tyres also have a fuel efficiency rating based on that (IIRC EU labeling mandates that).

Originally Posted by ringoism

hehehehe... interesting science there... So added vehicle /payload weight doesn't significantly apply extra load to engines/drivetrains (vs. wheels/tyres???)? I'll vote for tread design / rolling resistance here. And particularly odometer error on account of any increase in circumference. Easy to work out mathematically, as noted elsewhere.

Originally Posted by Poitive

Yes, science indeed is an interesting subject, even though I studied it way back and have quite lost touch. In case you are interested in science, please check up more on Rotational Inertia. Further smaller issues would be Unsprung Mass vs Sprung Mass.

Posting a few quotes for reference below:
1.
https://www.machinedesign.com/mechan...nsprung-weight

2.
https://www.tyreleader.co.uk/tyres-a...-weight-wheels

3.
https://www.oponeo.co.uk/blog/how-mu...s-a-tyre-weigh

~~~~~~~~~

- The 3kg increase in tyre weight reported by Manuuj might not be insignificant in context.

- Weight distribution on the wheel too has a role: weight on the outer side (tyres) contributes way more to rolling inertia than wheel towards the centre of the wheel.

- Rolling Inertia is a major factor in stop and go traffic (not as much if cursing at stable speeds as on a highway). Each time the car accelerates, much more effort is needed. It would also impact brake wear. It is directly related to the weight of the tyre.

- I had mentioned lower torque as compared to the Endevour also being a possible factor in another post in this thread. Similar extra effort for a high torque system (Endevour) would not be as taxing as it would be for e lower torque system (Gurkha). They aren't directly comparable in that sense.

- Besides the weight, increased diameter also implies more load on the engine each time the inertia needs to be overcome to get the car moving from standstill. Would impact FE.

- Not enough is there in this post about Rolling Inertia, and it is worth looking into for anyone interested in things from a technical perspective.

- Not related to FE: Though one generally tries for a higher sprung to unsprung weight ratio, in off-road situations, a higher unsprung weight has some benefits in stability of the vehicle.

~~~~~~~~~

PS: Something I haven't studied and might be relevant for someone wanting to go further into the science of it is Traction Effort.
PPS: On a side note: @ringoism, "hehehehe... ", multiple question marks, and a dotty style don't make for good polite reading, and not really encouraged on the forum.

The quotes from the links in the above post are missing and can be accessed by clicking on link to the post.

Originally Posted by ringoism

- As you clarified further on, unsprung mass has to do with suspension dynamics, nothing at all with FE.

- Rotational inertia is granted a potential factor, but again as noted, only if in a prominent state of repeated acceleration/ deceleration... If highway mileage is similarly suffering, this suggestion goes out the window.

- One thing I'm not sure anyone has asked is whether the toe-in setting could be significantly off... vs. other alignment specs, that one can create a massive amount of additional friction/ drag.

- 5.6kmpl (where double that would seem more normal) just seems inexplicable in terms of 12kg's additional inertial mass (after all it represents a very small load on the engine vs. the inertial load represented by the vehicle's total mass), or even tread design / rolling resistance, unless someone was running something a LOT wider/ more aggressive than stock... a few % difference in circumference will create an equivalent error...

- Sorry for any unpoliteness... sometimes I react a bit to what seem to be highly confident assertions on shaky/ incomplete bases.

- We all have lots to learn in some realm or the other.

Unsprung mass and FE: Not sure if you read the links and quotes shared. Please do. Further sharing another paper: I don't understand the science and details but might interest you, however the relevant part should be clear enough to most. Screenshots and pdf below.

Rotational Inertia and FE in the case being discussed: Manuuj has been talking about a city run. I guess that was missed - highlighted in the quotes above, so no, the suggestion does not go out of the window!

Alignment: Relevant point. Granted, as you might say.

FE and 12kgs: If you note, Manuuj reported about 9kmpl and expecting at least 10. About 10 odd percent, not double. In case you wish to consider the relevance of 12kgs in context, please refer to the tyre weights in my previous post and more about 'tyre weight and FE'. Much should be available via Google.

- Interesting way to say sorry, but accepted.
- I wouldn't call 'likely' and 'please check and consider' as 'highly confident assertions'. The impoliteness lead me to read up and they didn't sound shaky, as you might have noted.

- True, we all have to learn in some realm or the other; if one doesn't use the window in a rush

I did learn a bit from your lovely signature:
"Our greatest fear should not be of failing, but of succeeding at things in life that don't really matter"... (-Francis Chan)

And on that note, I bow out of this discussion; also in the spirit of keeping an ownership report on track.

Cheers!

Introduction:


Conclusion:


Mobile Friendly Abstract:


Complete paper's pdf:
Kastanos_2020_IOP_Conf._Ser. _Mater._Sci._Eng._747_012113.pdf

All rights of above paper to relevant owners.

~~~~~~~~~~
@Mods, the multiple quotes have not been done in any disregard to forum norms (for making it easier for mobile readers without long quotes), but to felicitate reading as the relevant posts were spread out over a few pages, and some of them were pretty long.

[Trojan]

Originally Posted by Manuuj

I am yet to make a detailed post on the sound damping work carried out on Asterix. I forgot to get the technical specifications of the damping used so haven't compiled my post yet.

In the meantime i went and got custom noodle mats made up for Asterix today. The stock mats are held down with locking pins and are not easily removable. As a result its quite a chore to clean them. Being black they show up dust and mud immediately after use.

Damn these mats are awesome, lovely execution and superb attention to detail as usual!!

These (mats and dampening) are coincidentally the exact two items which are under planning (on account of us not being available in Pune).
Had a detailed discussion on damping the doors and side panels of the Gurkha at Car Cupid (Pune). Also got to experience the work done on an Ignis, the doors felt heavy and super solid, no hollow metal there. The feeling inside the car was very cozy and super quiet too.
We were thinking though on how easy/feasible it would be to remove the inner panels towards the rear - at least in my Gurkha they have those plastic rivet type bolts - not sure if they can be re-fixed once removed.

[ringoism]

Originally Posted by Poitive

Introduction:
Attachment 2269380

Conclusion:
Attachment 2269381

Mobile Friendly Abstract:
Attachment 2269379

Complete paper's pdf:
Attachment 2269378

Well, I've been fooling around with cars and their performance for 35 years and been reading about them on a technical level before that, raced them on an amateur level, etc, etc - and honestly this is the first time I'm hearing that unsprung weight has a significant effect on FE - maybe I could all have missed this, and if so it would be embarrassing since I worked in the automotive industry, had done a fair amount of automotive-specific coursework in my engineering course, was an ASE member, and read voraciously for years... I mean, really embarrassing, ok?

Though even if I should end up embarrassed at some level, I honestly can't quite grasp (and am quite sure that no calculation could ever demonstrate) how 12kg's of additional unsprung weight on a 1.5 or 2-tonner could halve the FE... but anyway, will look into that. Maybe these "young engjneers" in Moscow are really onto something!!!

-Eric

[Kosfactor]

@Eric - OP had responded to me during the initial pages with the weight difference of stock vs aftermarket wheel setup, we concluded that it isn't that different. The aggressive tread pattern or additional tyre weight + diameter may change the FE from 10kmpl to ~9kmpl as an example but it won't be drastic.

Regardless of this I think in general a 2.2 ton vehicle NOT being particularly driven to extract maximum FE will struggle to achieve 10kmpl in town and if you keep the engine on the redline throughout a highway trip, it would drop even further.

[ringoism]

Originally Posted by Kosfactor

Regardless of this I think in general a 2.2 ton vehicle NOT being particularly driven to extract maximum FE will struggle to achieve 10kmpl in town and if you keep the engine on the redline throughout a highway trip, it would drop even further.

"Moderation in all things" is good path to trod...

But not sure there - maybe if assuming full-time A/C and lots of idling and generous throttle?

Here in often well-loaded hill conditions (non-highway), 10-11kmpl is a pretty roundly expected figure for any random diesel SUV/ driver running within the valley be it older/newer Scorps, Sumos, DI M&M's, Endy, Fortuner... somehow they all seem to fall somewhere around there in real-world local driving give or take a bit. The BSIV and up engines generally do better, more so if gently driven, friend's CR Bolero did 13.5 in Spiti, and heck, even Force Traveller vans supposedly manage 14-15 - and that's a lot of steel hauling a lot of people there...

Gurkha is tall and boxy and obviously aerodynamics are going to hurt it badly on the highways. Trojan seems to get 10-11, figures 12+ with more moderation and less payload/gear.

If not otherwise resolved, I'd still want to have a look at the toe-in... Production lines / PDI can have its share of lapses... how 'bout too little freeplay in the handbrake???

-Eric

[Poitive]

Originally Posted by ringoism

...first time I'm hearing that unsprung weight has a significant effect on FE
---
...how 12kg's of additional unsprung weight on a 1.5 or 2-tonner could halve the FE.

Since I chose to be out of the discussion as per my previous post, will limit to correction and clarification of what was said (much of it quoted in my previous post).

1. Again, it is about 10% we're talking about ~9kmpl vs ~10kmpl and not half the FE. If you follow the quotes, your post was a reply to my reply to Manuuj's post about FE. Nothing to do with the 5.6 reported.

It seems you mixed it up the 5.6kmpl reported by @shan2129.

2. The unsupring vs sprung mass was clearly mentioned as a smaller issue

Originally Posted by Poitive

...please check up more on Rotational Inertia. Further smaller issues would be Unsprung Mass vs Sprung Mass.

(formatting changed for the purpose)

3. No such claim of such a reduction of FE has been made by the authors of the paper or me. A combination of factors was mentioned as a reply to a post mentioning a 3.4% speedometer error, as worth considering (increased weight of the alloys (?), increased weight of the tyre, tyre tread and compound) and further elaborated based on questions raised. Besides other points in the several quotes in my previous post, what also might have been missed is the tread and compound part

So, it might not be a matter of any need for embarrassment or not; more likely simply a matter of missing out some parts of what has been written earlier.

Cheers!

PS: @ringoism and I have already initiated a PM conversation. Would prefer to avoid further discussion here. A 10% difference in FE on a fairly new vehicle is not such a big matter. Way wider variations are routinely reported on the FE thread on the forum.

[shan2129]

FE update - i did a run to Mysore last weekend, and got nearly 12 kmpl. I am guessing that I might be getting 9-10 kmpl within city.

[Manuuj]

Originally Posted by Poitive

1. Again, it is about 10% we're talking about ~9kmpl.

Originally Posted by ringoism

But not sure there - maybe if assuming full-time A/C and lots of idling and generous throttle?
If not otherwise resolved, I'd still want to have a look at the toe-in... Production lines / PDI can have its share of lapses... how 'bout too little freeplay in the handbrake?
-Eric

My FE has now settled around 9 to 10 kmpl within the city. I guess the larger diameter tyres and as Eric said the shape and weight of the Gurkha will mean these kind of figures are probably normal now.

I have had the Handbrake checked as well as the Allignment too has been fixed. Good points there Eric!

Originally Posted by Trojan

Damn these mats are awesome, lovely execution and superb attention to detail as usual!!

The mats are quite good as the dust just disappears within the noodle structure. A quick wash with running water is all it takes to have them looking like new again.

There was a slight problem though. They tended to slip and shift underfoot which is a safety issue. I had some good quality velcro lying about at home so had it stitched to the back of the new mats and correspondingly onto the top of the OE rubberised matting. Now they stay in place and remain easy to remove and clean.

The Red thread that is visible on the top of the noodle mat is to let the person removing them know where to pull them up from.


Now they stay in place and dont move about while driving. Have had the same length of Velcro stitched on the forward portion of the mats also.

[Manuuj]

Asterix will soon feature on a YouTube review of the '21 Force Gurkha by "91Wheels". We did the shoot today and it was quite an experience. The amount of camera equipment they invest in is commendable. I am sure the video will be have a very professional feel to it.

Here are a few pics as a sneak preview

[bangaloreguy]

Enjoyed reading this thread and this is a great vehicle. I hope it's popularity increases over time as I feel it has an authentic 4*4 look unlike the Thar.

[Petroleus]

Congratulations Manuuj !

This is on smile inducing ride with trueblue offroad creds

Not sure if I missed it, but has Force Motors announced a NCAP rating on the current Gurkha?

[Manuuj]

An ownership review of Asterix.

https://youtu.be/Aiofh1PRjUc