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Traxxion has an interesting utube about tire pressure. Conventional wisdom on the boards is that the fronts should be around 40 PSI, with the factory recommending 36.

Traxxion recommends that the fronts be run at 32 front and 36 rear unless 2 up, when he recommends an increase to 38.

He believes cupping is called by insufficient damping, and that the higher tire pressures may help with tire cupping, the higher pressures aren't worth the safety trade off. He believes it what he calls "rock hard tires" significantly reduce the size of the contact patch and deliver a punishing ride.

I had an issue with the manufacturers recommendation of tire pressure on my motorhome being too high. I weighed it and adjusted the pressures according to the tire chart and handling really improved.

Has anyone tried the lower pressures?
 
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I tried his recommendation last year. I liked the way the bike handled but the tradeoff is reduced mileage. I got 30% less mileage on my tires and they cupped really early. I'm back to 41/42.
 

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I ride two up a lot so run 36 and 41. I also have Traxxion suspension so never have any cupping. Don't know about tire wear as bikes eat tires way too fast anyway. Just grit my teeth and buy more.
 

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I had an issue with the manufacturers recommendation of tire pressure on my motorhome being too high. I weighed it and adjusted the pressures according to the tire chart and handling really improved.

Has anyone tried the lower pressures?
On your moho, as well as any tire with a DOT stamp on it, and including motorcycles too, the most basic function of a tire is to carry the weight of the vehicle. In the tire industry, we'd sometimes call one nothing more than a pneumatic airbag ... so many cubic inches of air give the tire the ability to carry a certain amount of weight. If a tire does not have enough air (psi), the tire over heats, adhesive bonds within the tire starts breaking down, separation of various layers begin to happen, and soon a blowout will occur. It simple science. Especially when it comes to trucks, you did the correct thing by weighing each axel, and adjusting the psi accordingly. There is a standardized chart in a published "trade book," that I believe was called a Tips Book, that all Firestone and Goodyear stores had behind the counter. We frequently look up such information to offer proper advice. Your tire size with its load range would be listed with air pressures showing how much weight each tire can carry. Hopefully you used something similar when adjusting your air pressures.

But todays tires must be far more than just a pneumatic airbag. They have to stop the vehicle, accelerate, corner, provide good fuel economy, roll quietly, provide good handling and ride quality ... etc. In all company training sessions where tire engineers were sent out to field train us, here is what we were always taught. Our training was for the passenger/LT truck tire industry. So long as your psi is good enough to cover the weight of each axel, and if the differential of pressure from front to rear is respected, your are good to go. Every tire has a max. air pressure, and a tire properly aired should never exceed that. Tire pressure should be air when cold, and cold was considered less then 1 mile of driving, after sitting at least 4 hours.

As for running something other then what the vehicle's tire pressure sticker says. All the attributes I listed above are affected. Certainly a lower tire pressure offers a smoother ride and larger contact patch for traction and braking.

If I recall, the once fastest GL1800 rider on Deals Gap, Mr Craig Cain, would air his tires to 36/41, get his tires nice, hot, and sticky, then lower their air pressure 36/41. He rode solo, with empty cargo compartments, and only 1.5 gals of gas in the tank when practicing laps at the Gap.
 

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I tried his recommendation last year. I liked the way the bike handled but the tradeoff is reduced mileage. I got 30% less mileage on my tires and they cupped really early. I'm back to 41/42.
Are you running any kind of aftermarket suspension ?
 

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I've been running the Traxxion tire pressure recommendation for 4 or 5 years. I haven't noticed any unusual tire wear pattern and to me the smoother ride is well worth any reduction in tire life.
Same question. Are you running any aftermarket suspension?
 

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I'm all for a softer ride and am willing to trade tire life for it but does lowering pressure affect TPMS? I wouldn't want a bunch of low-pressure warnings.
 

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I had the full Monty done this spring. Running Dunlop Elites. I had been running 42/40 in them, and prior to the install had a hell of a cupped front tire. My installer and I had a convo on pressure and he had noted what mine were inflated to. He suggested I try 38/35, and I have run that all summer, about 7K miles. I do think it rides better, and the Traxxion upgrade obviously makes it difficult to ascribe better handling based on tire pressure. I do plan to go back the "stones on the next tire change.

WIth respect to cupping, I would not necessarily blame that on tire pressure, my installer advised that firstly the stock steering head bearing are awful, and secondly the stem nut is often very loose. Mine was loose to the point of being dangerous and the bike only had 15K Miles. And since I did the Traxxion, no cupping in 7K miles. The fellow that did mine has done several hundred Traxxions and states he's seen the loose nut on the stem quite often.

YMMV
 

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Are you running any kind of aftermarket suspension ?
Yes, I'm running Racetech suspension front and back. Also have my suspension set to 25. I've been running on Avon Cobras for the last few years if that makes a difference.
 

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Years ago with my 2003 before I upgraded to Traxxions suspension, I tried running 41psi in the front tire to stop the front tire cupping...the tire still cupped and the ride was harsh. I went with the Traxxion AK20 suspension and ran 36psi and the bike rode plush and I never seen a front tire cup again..rode 85k miles with that setup..Traxxion suspension is the best mod you can do with the old model wing.
 

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I had the full Monty done this spring. Running Dunlop Elites. I had been running 42/40 in them, and prior to the install had a hell of a cupped front tire. My installer and I had a convo on pressure and he had noted what mine were inflated to. He suggested I try 38/35, and I have run that all summer, about 7K miles. I do think it rides better, and the Traxxion upgrade obviously makes it difficult to ascribe better handling based on tire pressure. I do plan to go back the "stones on the next tire change.

WIth respect to cupping, I would not necessarily blame that on tire pressure, my installer advised that firstly the stock steering head bearing are awful, and secondly the stem nut is often very loose. Mine was loose to the point of being dangerous and the bike only had 15K Miles. And since I did the Traxxion, no cupping in 7K miles. The fellow that did mine has done several hundred Traxxions and states he's seen the loose nut on the stem quite often.

YMMV
Curious as to why you would have chosen such high front tire pressure when the factory recommendation is 36psi? The installer suggestion reflects that.
 
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Curious as to why you would have chosen such high front tire pressure when the factory recommendation is 36psi? The installer suggestion reflects that.
It was partially due to wanting to avoid the cupping once I replaced the front tire, ( New bike, 7K miles, cupped, couldn't believe it!) as well as various posts on the topic where posters advocated for the higher pressures. And lastly, I was running those pressures for years on my Valkyrie with great results.
 

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....

If I recall, the once fastest GL1800 rider on Deals Gap, Mr Craig Cain, would air his tires to 36/41, get his tires nice, hot, and sticky, then lower their air pressure 36/41. He rode solo, with empty cargo compartments, and only 1.5 gals of gas in the tank when practicing laps at the Gap.
So, is the Mr. Cain no longer riding or is there someone faster now?
 

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So, is the Mr. Cain no longer riding or is there someone faster now?
Because of shoulder issues, a GW was one of a few bikes he could ride. A couple of years ago he either a left hip or knee replaced, and as time went by, mounting and holding up a Wing became too painful. So he finally sold his Wing. He's always had something else to ride, and I think he has a 1000cc Yami or Kaw but it's not a crotch rocket. Apparently a crotch rocket has handle-bars mounted in front of the forks, and those, because of his shoulder he cannot ride. So it's something like a crotch rocket with bars mounted aft of the forks like a Wing has. I asked him if it is fast, and his response was OMG it is ****ing fast. He rides the gap all the time, and he also takes pictures for US129 photo.

He sold his Wing to some old man, and apparently that old man cannot believe how fast it is. Little does he know that he'd bought the fastest 5th gen out there. It not like one can advertise that when selling it.

When Yellowwolf quit riding, and since there was no one else to beat, he's slowed down some.
 
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