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By the way, while you did install the four fork mounting bolt per the plans, you might consider turning them nuts up as Wayne Tyson mentioned.
Since the tire rubs mostly on 1/2-2/3 of the tire, I am leaning towards a mis-shapen/bulging tire... I have the tires set at 15 PSI. Lowering the pressure to 12 PSI did not stop the rubbing. I can't imagine that increasing the tire pressure would do anything but make the rubbing worse by making the tire bigger...
The spacers are the correct ones and on the correct sides...(longer spacer on co-pilot/passenger's side.) At this point, I think I will get another tire and see if it is more uniform and does not rub. I will save the current nose wheel tire as a spare for the mains, where fitting inside a fork isn't an issue!
Wow! And I thought mine was close! But you seem to be clearing the bolts, which mine wasn't. My A&P buddy says that the three threads rule isn't set in stone, but one should dab some orange marker paint on and add checking it for movement on the exterior check list.
I'd like to know how much flexing the tire body does in use. I'd like to lower the pressure for off-pavement stuff and increase it for paved surfaces. Next time I'm at the hangar, I'm going to check, but I thought there was a range of pressures allowed.
Thanks for bringing this issue up--I'm learning (no fake news or alternative truths, I hope).
I believe the rule is 1 to 3. Looks maybe like a shorter bolt would be good here.
If you google the Carlise web site, you'll see these are golf cart tires and there is only a maximum pressure. It's your aircraft and you can set it to whatever pressure you want, but for me, knowing it's the pressure that seals them, I'm setting to maximum pressure.
As for Nylocs, 2 threads is standard per Zenair construction standard (attached), which is from FAA AC No: 43.13-2B for certified aircraft. As a QA inspector in submarines it was only one thread. Go figure. In Experimental, it's really whatever you want, but anything less than flush is asking for failure.
This is what ours looks like https://youtu.be/0GQlvZc2ikg
Update! We ordered a new tire (WalMart $52.41 - free delivery to the house). We put it on today and all is well. The original tire was misshapen/bulging on one side.
Glad you got it resolved. Zenith is really good replacing bad parts. Maybe you should ask them to send you a new tire for spare.