![]() | #481 |
Senior - BHPian ![]() Join Date: Jul 2008 Location: in a Toyota!
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| ![]() thanx for all the comments and replies on the matter of rear and front tracks being of smaller and bigger size, respectively. but are there any drawbacks or flaws of this kind of set up on a vehicle? |
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![]() | #482 |
Senior - BHPian ![]() | ![]() In a rear wheel drive car it seems to make sense to have a wider front track for steering stability. Imagine you pushing a wheel barrow with a wider front track. Now imagine you pushing a wheel barrow with a track narrower than your feet, chances are it will be all over the place and a nighmare to steer effectively. Same way in a front wheel drive car it may make sense to have a wider rear track, so the rear tracks more efficiently (like a man pulling a kart) I am just visualising a wheel barrow/man powered kart scenario. I wouldn't know more technically but logically it seems to make sense Last edited by DKG : 16th January 2010 at 10:39. |
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![]() | #483 |
Distinguished - BHPian ![]() ![]() | ![]() I have a book on automotive engineering. Quoting from there: At basic level: Wide track decreases load transfer which is generally good for getting grip on that end of the car. One disadvantage is that you increase usually weight, because of longer A-arms, push- or pullrods, tierods and driveshafts. Also the moment of inertia in yaw is increased a lot, because it is dependent on the lever arm of your wheels. At the rear of the car: A narrow track can be an issue with the drive shaft. You need more angle for the same vertical movement of the wheel you would like to allow. A shorter track at the rear is also helpful as during turning there will be lesser difference between the radius of curvature between the wheels, not causing the differential to lock to often. Rear wheels closer tgether aids in traction, for example dragster rear tires are very close. Having the front track width wider than the rears also helps with being able to change direction more quickly. Why? Because: The front wheels will have to absorb all the load transfer... that means the outside front tyre will be much more heavily loaded (twice as much load transfer to the outside front tyre than an equivalent car with equal front and rear track).... and that will promote understeer. Source: RaceCar Engineering EDIT: infact we have a thread on teambhp on this which never came to any conclusion. Maybe we can continue discussion about this there. http://www.team-bhp.com/forum/techni...-v-s-rear.html Last edited by Tejas@perioimpl : 16th January 2010 at 11:09. Reason: see edit |
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![]() | #484 |
Senior - BHPian ![]() | ![]() Hi guys, Even i had problem initially with difference in the track of Bolero range of vehicles except for Invader. The wider front track as Trammway said was to accomodate tighter turning circle. The rear was left just like that because- If you put wider track rear axle, it may foul with body work due to articulation. This may require further investments to cut the body and the door line which is expensive. Invader was newly developed and has a wider and higher body. Plus due to inverted leaf over axle type suspension and commonality of parts i think the Maxx festerra rear axle was adopted. Plus what ever tejas said holds good for handling purposes. However this is a big draw extreme back off road specifically for competitions. Imagine if you have to cross a stream on log of wood. How would you accomodate 100+mm difference on a just two wood logs running parallely? Thats why which ever vehicle was developed purely for off road duty like LC, defender and Jeep warangler to name few will not have such wide difference in track. Now the question is why cant invaders wider axle be adapted to thar? The reason is wider the axle the wider should be the spring points, i.e nearer to the ends of axle. Else there would be tremendous body roll if the springs are not stiff. (1985 to 1989 MM540 and first generation Maxx festerra's) Thar according to me is developed under tremendous constraints considering market is very small. Expect all the revisions to happen (including MLD/LSD etc) as and when both export and domestic markets pick up. Demand of suitable rear axle width has to come from abroad. Till then who ever is doing logwood crossing and competition specific terrain have to satisfy with spacers. Last edited by vinod_nookala : 16th January 2010 at 13:57. |
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![]() | #485 |
Team-BHP Support ![]() ![]() Join Date: May 2004 Location: Bangalore
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| ![]() @vinod: It shouldn't be a BIG problem since the difference of approx 100 mm is shared between 2 sides, so one side will go in by 50 mm which is negligible right? |
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![]() | #486 | ||
Senior - BHPian Join Date: Jul 2009 Location: Calcutta
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| ![]() Quote:
Quote:
Sutripta | ||
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![]() | #487 | |
Senior - BHPian ![]() Join Date: May 2006 Location: Greater Chennai
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![]() | #488 | |
Senior - BHPian ![]() | ![]() Quote:
It matters in such cases! ![]() | |
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![]() | #489 |
Team-BHP Support ![]() ![]() | ![]() We did such a log crossing in Kakkabe (Coorg) OTR, Gypsy to Telcoline did cross the bridge, although it looked very narrow, just enough for a Jeep. Vinod, aren't you supposed to be on vacation now? ![]() |
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![]() | #490 |
Team-BHP Support ![]() ![]() Join Date: May 2004 Location: Bangalore
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| ![]() Yes thats what i meant, the tyre width itself will take care of such variation unless its those thin NDMS thingies? |
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![]() | #491 |
BHPian Join Date: Dec 2007 Location: Kanchipuram
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| ![]() If I take this ' Done up ' Thar for a OTR.I need Arka's 1 ton just to pick up the plastics/lights/air intakes/some I don't know things etc etc I leave behind. |
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![]() | #492 |
Senior - BHPian ![]() Join Date: Jul 2008 Location: in a Toyota!
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| ![]() so this discusion about the front and the rear track measurments concludes that THAR will be getting bolero's front and rear tracks, to enable MM to keep the costs down! so does that mean the export version of THAR also has a similar set up of the front and rear tracks as the Desi Thar or its different? Could any one please comment on the front and rear tracks in the following photos i have attached? |
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![]() | #493 | |
Senior - BHPian Join Date: Mar 2006 Location: goa
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Why would M&M develop two different chassis, when it knows that THAR will be sold in very small number compared to other vehicles in the portfolio. Last edited by dinar : 17th January 2010 at 01:26. | |
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![]() | #494 |
Senior - BHPian ![]() Join Date: May 2006 Location: Greater Chennai
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![]() | #495 |
BHPian Join Date: Nov 2007 Location: Doha
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