20” Tyre Pressure

[dcpen43]

OMG. Dropped pressures to 44 and 42 and it's like a different ride. No pop top squeak, no cringing everytime you run over a small rut in the road, significant reduction in road noise. Why, of why were my tyres over inflated in the first place.

 

[Bigsidavies]

OMG. Dropped pressures to 44 and 42 and it's like a different ride. No pop top squeak, no cringing everytime you run over a small rut in the road, significant reduction in road noise. Why, of why were my tyres over inflated in the first place.

That’s still quit high for 20’s. Most people run 38 or 40. Check that you don’t start to get excessive wear in the centre of the tyre over time.

 

[dcpen43]

Camping next week so will drop it further. Thinking of taking the 20s off all together anyway. Brushed the curb and ended up with irreparable sidewall damage on a new tyre. Expensive mistake I will not repeat.

Think the originals were over 50psi because someone assumed tyres were Commercial rated.

 

[Bigsidavies]

Keep the 20’s, stop hitting the kerb.
That pic you put up looks like it could just be you’ve ripped off the thick lip of rubber which is only there to protect the rim. I’ve done that in the past on the car and glued it back with rubber glue.
Obviously, not recommended if you’ve cut into the actual sidewall itself.

 

[dcpen43]

will persevere

 

[tedscaravelle19]

hi, I am also struggling to find the correct tyre pressures on a 20s. I have a T6,1 camper conversion (rock n roll bed, kitchen, pop top etc so fairly heavy even on its own) . it is lowered on B14s. Does running 40psi for commuting sound ok? Please could someone assist me with the correct pressures when the van is loaded say with 4 people, luggage and a couple of bikes. thanking you in advance.

 

[T6_FunBus]

Just to report back, for me, with a light van (estimated <2100kg) running the budget 275 35’s the van came with on 20’s @ 36psi has made no negative impact to fuel consumption, has increased comfort a small amount and seems to have perhaps improved grip. I will continue to run @36psi.

 

[Dm85]

Yes, we are down to 36psi, tyre wear seems better at this pressure and obviously a better ride.

I’m running 245/45/20 on a T30 will 36-38psi be ok?

 

[BognorMotors]

I’m running 245/45/20 on a T30 will 36-38psi be ok?

Yes

 

[S18RVW]

I've been running 255/40/20 and 245/40/20 at 42psi for the past year and they have completely even wear all the way across

 

[Dm85]

I was running 36psi on 255/40 a
101Y eagle F1 and was getting a lot of road rumble and jarring when hitting imperfections so upped it to 40 psi and the extra air made it better. My theory is 101 rated tyres may need more pressure than 103 rated I guess.weight of van etc…. So many variables……

 

[Drive Wayne]

OMG. Dropped pressures to 44 and 42 and it's like a different ride. No pop top squeak, no cringing everytime you run over a small rut in the road, significant reduction in road noise. Why, of why were my tyres over inflated in the first place.

40 all round on my cc2 20's, 'cos it's easy to remember and feels good. 42 when all the gear is in feels right at that.

 

[dcpen43]

40 all round on my cc2 20's, 'cos it's easy to remember and feels good. 42 when all the gear is in feels right at that.

i think i could do 40 and NOT notice the difference on my 20s

 

[dcpen43]

40 all round on my cc2 20's, 'cos it's easy to remember and feels good. 42 when all the gear is in feels right at that.

Another tyre pressure question… Van is a T6 T32 Kombi, 2WD, 200hp with DSG.

OEM tyres are awful 215/60 R17C 104/102 (commercial tyres). VW recommended pressures are 57/48 psi F/R unladen and 58/58 psi laden. I can’t find a load/pressure chart for these commercial tyres but the narrow pressure range for the rear (only 10 psi) implies the rear is about 80% loaded in an empty van. That makes no sense; another post said rear axle load on an empty T32 is only c. 45% of max. That makes sense, so why 48 psi for an onloaded van?

I think kerb weight for my unloaded van (just 2 people & diesel) is about 2,200 kg, assuming c. 1,450 kg front / 750 kg rear. ‘Loaded’ for my typical usage is around 2,800 kg, assuming c. 1,500 kg front, 1,300 kg rear.

I am swapping to 235/55 R18 V 104s. The ETRTO load inflation tables for these tyres would put the pressures at around 33/22 psi F/R unladen (22 psi minimum recommended) and 33/29 psi laden. That seems crazy low. Am I missing something?

If I use the maximum design axle load to set the loaded pressure (1710/1720 kg F/R), ETRTO tables give 41 psi F/R. If I then subtract 550 kg from the rear (275 kg per tyre) for the unloaded case, would equate to 26 psi. In summary, 41/41 psi F/R for the laden case and 41/26 psi for unladen. Small cars like Ford Fiestas have a large pressure differential on the rear for loaded vs unloaded, so that makes sense to me for an empty van.

Thanks for any thoughts or advice.

18s should be somewhere between the commercial 50 and 40s for 20s

 

[MrGreen]

I’m running 20’s with Michelin Pilot Sport 4S 275/35 at 38-40 psi.

Wear is more on the outer of the tyre but still got 3-6mm left after 29,000 miles. Van has full conversion, so approximately 300kg load weight.

Not cheap tyres but I’ve run 4S’s on other vehicles and got good mileage from them. Therefore I’ve put them on my van to test them.