Sailun tire inflation

[Ray,IN]

Originally Posted by buc1908

I run Sailun for 6 years now but I keep the psi at 105 -110.I never heard to inflate at 80psi.

What was the original tire inflation recommendation? The same pressure will support the same load, the increased load range of the Sailun tires is immaterial, the added safety factor is very material.
I ran Sailun tires on my 15,500# 5er to Alaska and back without any issues, then for another 3 years until I sold that 5er. The tires were always inflated to 80psi, which was indicated on the Federal Tire Placard on the 5er.

[grindstone01]

Originally Posted by Tireman9

Are your scale weights just the total of the 4 trailer tires or do you have individual tire loading? IMO it is unreasonable to expect perfect 50/50 load split between axles (especially with the weight hanging off the rear. It is also unreasonable to expect side to side load split of 50/50.


You said you were an engineer. Electrical, Mechanical, or Chemical ?

ME, I do not have individual tire wt's, but they would not be off by 1000 pounds and with the equalizer, the tires will share the wt somewhat. If the axle wt were balanced, then each rim should be 500lb under loaded.

[grindstone01]

Originally Posted by kdauto

Depending what kind of engineer you are, you possibly know how to examine metal to see if fatigue or a sudden stress broke the rims. I can't see anything other than an overstressed setup eventually fatiguing the wheels.

I don't know how you weighed your rig. If you had the swivel wheel and motorcycle on it the 700 lbs should have been supported by the swivel wheel setup so you really DO have 14 000lb+ on the 2 trailer axles. Add the stresses of swivel wheel hitting potholes/bumps, extra flex on the frame, higher tire psi... Have you ever thought about larger dips and bumps and how that swivel wheel works? I suspect that bike and rack is hanging midair briefly at times. This can cause a LOT of frame stress and extra axle loads.

The rear axle's are supporting 14340 lbs as weighed on a scale. The swivel trailer does not hang in mid air during bumps, it is supported by 2 pins off the frame and can rotate 180 deg up and down if allowed. I am aware of the added frame and axle stress, but I am not sure how that would effect a rim failure that is a higher rating than the applied loads? My point is the tire sidewall needs to flex because the dynamic stress of a pot hole and too high of a tire pressure can result in a stiff side wall that can crack a rim.
Both cracks were in the same spot on both rims on the pass side. It would have been unlikely that the same spot would have stress cracked from other pot hole hits that would have stressed other areas. The remaining 2 OEM rims don't show any stress cracking.
I know what the root cause was!!

[kdauto]

Originally Posted by grindstone01

The rear axle's are supporting 14340 lbs as weighed on a scale. The swivel trailer does not hang in mid air during bumps, it is supported by 2 pins off the frame and can rotate 180 deg up and down if allowed. I am aware of the added frame and axle stress, but I am not sure how that would effect a rim failure that is a higher rating than the applied loads? My point is the tire sidewall needs to flex because the dynamic stress of a pot hole and too high of a tire pressure can result in a stiff side wall that can crack a rim.
Both cracks were in the same spot on both rims on the pass side. It would have been unlikely that the same spot would have stress cracked from other pot hole hits that would have stressed other areas. The remaining 2 OEM rims don't show any stress cracking.
I know what the root cause was!!

The root cause is an overloaded trailer, not a tire issue. If you had a 17000 or 18000 lb GVWR trailer I suspect the wheels, tires and axles would be a higher load rating or a triple axle.

I'd also agree it would be wise to get individual wheel weights. I've read that some RVs can have 1000 lbs difference left to right, not rare. When under GVWR by a few thousand lbs=no issue. At or well over GVWR,well then...

JMHO

[Tireman9]

Originally Posted by grindstone01

The rear axle's are supporting 14340 lbs as weighed on a scale. The swivel trailer does not hang in mid air during bumps, it is supported by 2 pins off the frame and can rotate 180 deg up and down if allowed. I am aware of the added frame and axle stress, but I am not sure how that would effect a rim failure that is a higher rating than the applied loads? My point is the tire sidewall needs to flex because the dynamic stress of a pot hole and too high of a tire pressure can result in a stiff side wall that can crack a rim.
Both cracks were in the same spot on both rims on the pass side. It would have been unlikely that the same spot would have stress cracked from other pot hole hits that would have stressed other areas. The remaining 2 OEM rims don't show any stress cracking.
I know what the root cause was!!

Does your trailer present any side loading into the RV? As you know from your experience in wheel design the durability tests for wheels are a combination of vertical load along with significant cyclic side to side loading and it is the cyclic side loading that usually finds the weakest part of the wheel disk. I experienced this on my race car, when I failed two aluminum disks of the multi-piece racing wheels.


Wondering who made your cast aluminum wheels?

[keastab]

Originally Posted by IC2

I had a tire go flat while backing in my driveway. A valve broke. The valve was replaced and no damage seen - but that tire is now suspect and at 5years old about aged out for RV use.

Since I've been hearing/seeing rave reviews about Sailuns, am considering installing all four. Sailuns are rated full capacity at 110 psig. The wheels on our 5er are rated either 80 or 94 - there is a conflict in the wheel manufacturer's, Sendel, website.

The Sailun ST235/85R16 is rated 3640# capacity at 80 psig and 3800 at 95 psig. These figures are from the Sailun inflation chart

Question is, has anyone run these tires on an RV at 80psig? Any abnormal wear patterns?

I've got 6 newer ones on My RV. 19.5's though I switched over to them from Michelins because the delivery trucks (3) of mine have been using the 16's and 19.5 for over 9 years now with 1 minor problem of one tire being super hard to balance ( 16"s) the 19.5's have all been excellent. I run mine @ 90ish (4 wheel corner balance is lighter on one corner that the other 3 so it gets 5lbs less@ 85) been on there for 4 years and over 27k.

[IC2]

Originally Posted by keastab

I've got 6 newer ones on My RV. 19.5's though I switched over to them from Michelins because the delivery trucks (3) of mine have been using the 16's and 19.5 for over 9 years now with 1 minor problem of one tire being super hard to balance ( 16"s) the 19.5's have all been excellent. I run mine @ 90ish (4 wheel corner balance is lighter on one corner that the other 3 so it gets 5lbs less@ 85) been on there for 4 years and over 27k.

Thanks for the info. It appears that Sailuns are most likely in our 5ers immediate future (as soon the weather clears to spring).

[paul65k]

Originally Posted by IC2

Thanks for the info. It appears that Sailuns are most likely in our 5ers immediate future (as soon the weather clears to spring).

Not an answer to your original question as you seem to have already gotten that but some real world Sailun expereince.

I replaced the Goodyear Marathon G rated tires on our 14K 5er 3 years ago with Sailun and put about 20K miles on them prior to selling and moving to a Class A Pusher.

In our time with them here in the AZ summers, mountains and many, many times over the Continental Divide we found them to be OUTSTANDING tires and much more solid than the Goodyears they replaced.

They were always monitored for pressure and temps and all were consistent across all tires.

I will recommend and purchase these tires again whenever I have the chance in the future

PS.....I would try to match tires to rims if you can. G-rated tires should be mounted on rims rated for them, E-rated rims (80 PSI) are designed for E rated tires.

All the best in your search and pending purchase....you are on the right track

[Tireman9]

Originally Posted by IC2

Thanks for the info. It appears that Sailuns are most likely in our 5ers immediate future (as soon the weather clears to spring).

When you install the new tires be sure you use bolt-in metal valves as seen HERE. When properly installed - proper torque - I don't think you will need to worry about them breaking.
Do you know why your old stems broke?
Were you running TPMS?

[IC2]

Originally Posted by Tireman9

When you install the new tires be sure you use bolt-in metal valves as seen HERE. When properly installed - proper torque - I don't think you will need to worry about them breaking.
Do you know why your old stems broke?
Were you running TPMS?

I already have a brand new set of Milton clamp (bolt) in valve stems.

The old stems were the heavy duty, metal inner body snap in but had aged out. The failed one crumbled in my hand. The wheels were made in 2012 for our 2014 5er so suspect that the stems were installed along with the original, long gone China Bomb Tow Max tires then. I was not using my TST TPMS since the trailer had been sitting at a CG for about 6 weeks after our late summer trip with the trip home is usually a non event