Importance of precise deflation

[Rahimdad]

Great topic @Frederic. Also good to note that the tire pressure we suggest to you as newbies is within safety constraints. We do not want you to pop your tires out on your very first drive. The accuracy of your gauge can be checked in several ways. I have seen several modern vehicles having TPMS (tire pressure monitoring system), a lot of member with this technology double check their tire pressure gauge against what is shown on their dash. This is one way to make sure you're down to the right pressure. Another technique is to check it against the tire inflator at any petrol station.

Once you have ensured your tire pressure gauge is accurate it's time to experiment. Say we started you with 15 PSI and you're comfortable with the drive, try going 1 PSI less, that is at 14 PSI. If that too is comfortable, keep dropping your tire pressure till you find the best figure for your setup. So example is I reduced my tire pressure down to 10 PSI with my current setup, however since I did not feel any difference between 10 PSI and 11 PSI I stuck with 11 PSI to avoid any chance of pop-outs. Pop-outs are mainly due to driving at lower air pressure, but also can be due to aggressive driving style. Pop-outs in themselves are a whole new topic and will be dealt with in another episode of "if you don't know, now you know"

[Lorenzo Candelpergher]

I totally agree with @Rahimdad's suggestion to experiment.

When I started offroading with my Nissan Patrol Y62, I was initially deflating to 18psi, but would often get stuck. I then started deflating more, to 15psi, but I had a (record) number of pop-outs, mostly due to a) having low profile tires and b) being still inexperienced in controlling power and fishtailing. 

The real game changing moment for me happened when I started driving with much less power (and for a long time in D and watching actively my RPMs to learn how to use the power and what the car would do in the absence of my direct action) and, most importantly, when I shifted from 20" to 18" rims with high profile tires, a fundamental requirement to make it to Intermediate. 

With less risk (and less mental fear) of pop-outs, I started to deflate more and more as I got more experienced, finding out that 12psi works almost always quite well, with 10-11psi being optimal in very soft sand conditions. 

[M.Seidam]

Totally agree with @Frederic ( nice profile pict by the way ☺️ ) @Rahimdad and @Lorenzo Candelpergher to highlight such an important subject . 
Actually it makes a lot of difference after finally you get the balance of the optimum tyre pressure which helps you to float Nicely but also without getting popped out in your own particular vehicle. 
after practice I am on 10 psi always and till this moment no pop out . But this doesn’t mean that I will not. It’s all about practice and drive style but generally speaking to what the particular drive level dictates for safety reasons i was going from 15 to 10 psi gradually and now Settled on 10 psi .
 

 

Edited February 9, 2021 by Mohamed Seidam

[Thomas Varghese]

7 hours ago, Rahimdad said:

Great topic @Frederic. Also good to note that the tire pressure we suggest to you as newbies is within safety constraints. We do not want you to pop your tires out on your very first drive. The accuracy of your gauge can be checked in several ways. I have seen several modern vehicles having TPMS (tire pressure monitoring system), a lot of member with this technology double check their tire pressure gauge against what is shown on their dash. This is one way to make sure you're down to the right pressure. Another technique is to check it against the tire inflator at any petrol station.

Once you have ensured your tire pressure gauge is accurate it's time to experiment. Say we started you with 15 PSI and you're comfortable with the drive, try going 1 PSI less, that is at 14 PSI. If that too is comfortable, keep dropping your tire pressure till you find the best figure for your setup. So example is I reduced my tire pressure down to 10 PSI with my current setup, however since I did not feel any difference between 10 PSI and 11 PSI I stuck with 11 PSI to avoid any chance of pop-outs. Pop-outs are mainly due to driving at lower air pressure, but also can be due to aggressive driving style. Pop-outs in themselves are a whole new topic and will be dealt with in another episode of "if you don't know, now you know"

@Rahimdad what you wrote is true. When I started off as an absolute newbie I was really afraid to reduce the tire pressure to less than 18 psi as it was H/T tires even though @Frederic the Marshal insisted I keep it at 15 psi. Well I agreed but didn't go lower than 18 - the result was stuck after stuck. Then @sertac came to my aid and to my horror reduced the tire pressure to 14 psi. I couldn't resist his intervention and suddenly realized that stucks were getting eliminated and I could self recover. So I started to keep it at 14 psi for the rest of the drives. In a drive with @Ale Vallecchi and @Kalahari there was a bad stuck in too soft sand and they instructed me to reduce the tire pressure to 11 psi which I promptly did and could somehow come out and drove the rest of the drive with the same pressure. This new discovery that I could drive at 11 psi and still not have a pop out boosted my confidence so much to the point of arrogance that I started to drive at 12 psi as 11 psi was little uncomfortable for me regarding doubts about having a pop out. During the last fewbie plus drive with @Foxtrot Oscar I started the drive at 12 psi and regularly checked the pressure and could drive comfortably and with confidence. At the end of the drive when we were about to inflate I found 1 of the tires was running flat with no air to my horror. I doubted it was a puncture but as there was no choice in the evening in a deserted place and as I had the compressor I promptly inflated the tire and drove on. But the fear of a flat tire happening was lingering all through my drive back home. To my surprise when I checked the tire pressure in the morning it was holding the same I put the last night. This confirmed my doubt that it was a pop out which happened during the drive. The next drive with @Foxtrot Oscar I didn't go below the 13 psi and nothing happened even though I was constantly checking all the tires whenever I got the opportunity because of the previous pop out experience. I think for my car and tire 13 psi should be the optimum and anything lower could put me in trouble. 

[Varun Mehndiratta]

Thanks @Gaurav

 

Found this really nice video showing the importance of reducing the pressure and its impact. Dont focus on topic of video, just check the first 6 min focussed on tyre pressure. 

 

 

[Rahimdad]

@varunmehndiratta I'm going to try this on Faya this weekend.

[Varun Mehndiratta]

40 minutes ago, Rahimdad said:

@varunmehndiratta I'm going to try this on Faya this weekend.

Great will be there to witness in that case....just moved from wait-list to confirm on Faya drive...c u there..

[Thomas Varghese]

After some research on this subject I have come to the conclusion that we can reduce up to 2/3 of the manufacturer's recommended tire pressure to drive on sand but have to go back to the recommended tire pressure immediately as we hit the tarmac. 

[Rahimdad]

@Thomas Varghese the manufacturer puts on silly Dunlop Grandtreks or HTs in their new vehicles, if you are changing to a different brand or ATs you need to experiment to get the right deflation. Inflating them the moment you reach tarmac is good advise.

[Thomas Varghese]

2 minutes ago, Rahimdad said:

@Thomas Varghese the manufacturer puts on silly Dunlop Grandtreks or HTs in their new vehicles, if you are changing to a different brand or ATs you need to experiment to get the right deflation. Inflating them the moment you reach tarmac is good advise.

I put the Dunlop Grandtrek myself just before joining Carnity😪. Can't blame anyone. The tires have done only 15k kms so far and it will be a waste if I dump them now. Will keep it for 3 or 4 months and once they reach 50k to 60k kms will dump them for AT tires. So far the Grandtrek didn't give me much trouble though even when I drove them at 11 psi. Only once 1 tire ran flat and I suspect I did something during the drive so that one tire lost its air. Must have turned the car abruptly or must have hit something during the last leg of the drive as lights were totally faded after sun set. Moreover the tire just aired up and is still going great, whereas I thought the tire is finished seeing the marks on the side wall.