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@Alex M welcome to the club! Both the bigger club and the smaller circle! @Luke K P one more is added Will this be your first drive of your Raptor on the sand ? If yes, prepare yourself to add a level 11 of fun from a 0-10 grading system

Looks like another famous large scenic convoy is developing!

Yessir! Very excited to break it in! 😍

@Gary F looking forward to your video 23 going that’s remarkable

Agreed and thanks!

@Frederic, many thanks for the update! I have just spotted that the timing of the event also changed (from 11 til 11:30). Is it a hard stop or there is a chance we could finish earlier? My wife reminded me of some other (less interesting) commitments on Saturday so if we finish 11/11:30, I may have to drop this time Will def join next week though!

@Frederic hello mate! Nice to e-meet you and excited to join the first drive 😁 Details as requested... Please share your vehicle details - Make, Model, Color, and Year: Ford Ranger Raptor 2024 - Orange. Do you have any prior off-road experience? Only rocky trails with a jeep (not in UAE) some X Quarry sandbox stuff with the Raptor. Nothing in the desert. Confirm your vehicle has front and rear tow hooks/eyelets. Confirmed. Advise if you don’t have a programable radio and safety flag. I do have both. Plus a compressor and a deflator (camel brand one). Haven't used it yet though...

Sounds like there was a story behind a previous drive here. ..

Congratulations @Kartik Kumar Agarwal for reaching the Fewbie Level with Carnity Offroad Club. Looking forward to seeing you growing further and helping others to learn the art of offroading in a safe environment. Please make sure your Carnity user profile is always updated with all the latest Emergency contact details. P.S. Trip lead might deny your participation if you don't have required off-road gear. FEWBIE Drives Attended (Indicative) Minimum 5 Newbie drives are required within last 3 months for Fewbie promotion. What you'll learn Basic dune and sand reading Self-recovery techniques Shoveling at right place Crawling out of difficult situations Blip Blip - Coordinate steering and gas control Basic side sloping and hill climb Basic ridge riding and criss crossing Basic control over technical dunes Slightly faster pace desert driving Ability to manage stuck/refusals with radio Learn to control and avoid fishtailing Never fight or challenge gravity Skills required Enthusiastic and positive attitude Willingness to learn and help others Presence of mind and attention to detail Car Worthiness Any 4x4 vehicle with low range gearing Suitable approach and departure angle Off-road gear required Safety flag, tire deflator, tire pressure gauge, shovel, fire extinguisher, medical kit, radio (walkie-talkie), air compressor. Drive teamwork Manage second lead and sweep positions upon request Intuitive and proactive to support Trip Lead Observe recoveries and offer help, when needed Drive Joining Join Newbie and Fewbie drives Forum participation Active participation on the forum Share drive experience + feedback Share drive pictures in the gallery Post trip report after the drive

Congratulations!

Here we go again….🤦‍♂️ 😄😄

In this topic i am trying to go a little bit deeper into the whole concept of tyre sizes for offroading. Often, we start off with the stock 31inch tyres and find ourselves upgrading to a 32-33- or even 35 and more inch tyres, which might give benefits, or not ? First of all, we need to split into two categories: 1. Offroading in sand/dunes aka dune bashing. 2. Offroading in mountains aka rock crawling or wadi bashing. It is important not to confuse both, and they are almost opposite in terms of wheel size and i will explain this further below. We will not be discussing the fuel economy in relation of tyre size in below topic, nor the effects of the odometer reading, but rather focus on the performance aspect Category 1: Offroading in the sand/dunes What are the key parameters that determine the performance for driving in the dunes ? * Tyre weight (relation with overall size). * Surface area of each tyre on the sand when deflated. * Rolling Resistance * Tyre profile (aggressive knobby vs smooth HT tyre). Looking at above parameters, we would conclude that we are looking for a light tyre. The tyre profile in sand is not so important while driving but deflation is critical, and an AT tyre can be deflated further down safely compared to an HT tyre. We also noticed big differences during self recoveries on a smooth HT profile tyre vs a tyre with some moderate profile (AT tyres). Going for larger tyres results in higher weight on the axles, BUT seems to help with the contact patch area which is a good thing. So there is a balance that we are trying to strike. As a result of that you will see most offroaders in the dunes using similar tyres from the stock 31" to about 33" but not often 35" or more because of the negative effects that go along with that. (see re-gearing further down this topic). Category 2: Offroading in the mountains What are the key parameters that determine the performance for driving in the mountains ? * Surface area of each tyre on the rocks when deflated. * Tyre profile: AT Tyre is needed (HT tyre is not suitable for regular offroading in the mountains). * Ground clearance. As you can see, the key parameters for driving in the mountains are somewhat different because during rock-crawling you will be mostly in Low gearing and won't be needing the full top-end horsepower of your 4x4. The focus is more on using good torque and getting good clearance to overcome those boulders and other obstacles. As a result of that, bigger tyres would be performing better, simply due to the fact that you will win ground clearance without having to lift your 4x4, and the extra surface area of those tyres will give you better grip as well. And this is the main reason why we see so many Jeeps and Bronco's in the US on 35"-37" tyres crawling over boulders Re-Gearing: What's that all about ? source: https://www.4-wheeling-in-western-australia.com/differential-gear-ratio.html The differential gear ratio on a stock standard 4x4, are made to suit the tire diameter which the vehicle is originally came with. Using bigger diameter wheels/tires with stock ratios will cause more wear and tear on clutch, driveline and engine. Low range gear will also suffer as 1st gear low will now roll too fast as the tires are bigger, this becomes a problem when descending steep hills and climbing rocks and logs. Example: a stock 2005+ Toyota Hilux has 29 inch wheels/tires and fitting 33 inch rubber is quite bigger (4 inches in diameter bigger) this will cause the engine and entire driveline more stress and more power is then required due to the larger rolling resistance. The final gear ratio is suited for 29 inch, this ratio in this particular case is 3:5, referring to a chart it will state the same (29' recommended ratio is 3:5) and looking at 33 inch diameter the chart will recommend 4:1. Going by the chart any higher will make the 4x4 rev too much at highway speeds causing poor fuel economy. Changing the crown wheel and pinion is how the ratio is modified. Basically installing a new or reconditioned crown wheel and pinion with the recommended ratio will bring the 4wd driveline back to stock specification rpm and fuel usage. Once differential gear ratio mod is done the vehicle will regain its 1st gear low range and take off in high range will be improved or even back to stock. This chart is an approximate tyre size to differential gear ratio; it’s based on an RPM at 105 km/h (65 mph) and 4th gear on a manual transmission or 3rd gear on an automatic gear box (1:1 gear ratio). This is only a guide to get a general idea of which ratios would suit the vehicle in question. To get an accurate RPM the following steps and formula will give an accurate answer: Take a drive and record the rpm at 105 km/h (65 mph), the next step is to work out what the current ratios are in the vehicle. This can be revealed by calling the manufacturer or even calling a differential repairer giving him/her the Vehicle Identification Number, also known as VIN. Once all this information is known use the following formula to get the accurate differential gear ratio for the larger tires: Example: The rpm is 2806 at 105 km/h (65 mph), the current tires are 29 inch, the factory ratio is 3.73 and the new size upgraded tires are 33 inch. RPM: 2806 Stock tires: 29 inch Stock ratio: 3.727 New Tyre size: 33 inch 2806 = 65 x 3.727 x 336 / 29 (rpm = mph (not km/h) x diff ratio x 336 / tire size) Now the correct rpm is known for the vehicle (2806), the next step is working out what ratios are available for the vehicle, some makes and models won’t have as many choices as others. Say the following 3 ratios are available 3.909, 4.100 & 4.88. The new tire size wanting to be fitted is 33 inch and the rpm needs to be a close to the 2806 as possible in order to keep it to stock specs. Just a quick scan at the differential gear ratio chart it’s obvious that a ratio of 3.909 is too low at 2587 rpm, ratio of 4.88 is too high at 3230 rpm. But looking at 4.10 with the rpm at 2713 is the closest to 2809 stock rpm. New Specs: RPM: 2713 New tires: 33 inch New ratio: 4.10 Please share your experiences / feedback !