Tires: What types you use and why

Brian Jackson

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Hamburg, New Jersey USA
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GyroBee Variant - Under Construction
With all of the different tread patterns, profiles and other aspects to choose from, I'm curious what the folks here like and use for various reasons. I just ordered the landing gear components for my build and hadn't really considered this before now. After a phone call with a kind member here I will most likely be exchanging the tires I purchased for the mains with a round profile tire due to measurably less parasite drag over that of flat profile tires.

Anyway it's a topic that doesn't get discussed much so thought I would open it up for education.
 
These are the tires Abid uses for the AR-1. They are resilient, not low speed restricted and wear well. Since they are made for 'street use', they last for runway surface usage (which I use exclusively). For safety, I would only run them with tubes on split wheels.
Had them 1.5 yrs. and still have some 'molding nubs' and about 3/4 tread left.
 
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mark treidel;n1139552 said:
These are the tires Abid uses for the AR-1. They are resilient, not low speed restricted and wear well. Since they are made for 'street use', they last for runway surface usage.
Had them 1.5 yrs. and still have some 'molding nubs'.

I also have an AR-1 but the Heidenau tires are not was I was provided with. My AR-1 is number 15 so it's probably younger than yours. My main tires are labeled as "trailer" tires. They have more of a squared off profile than the scooter tires. I was a little surprised :eek: to see this when I had the wheel pants removed, but they have not given me any issues and I assumed that all ARs were equipped the same.
I can't recall the brand but I do remember "trailer" molded into the sidewall.
George
 
George, Mine is #14. It came with the tires you refer to. They were rubbing on the inside of the wheel pants and I did not want to 'grind off' the fiberglass inside so I switched to the tire above.
I do not like the 'trailer' tire flat profile for runway usage and they do present more drag as well. This tire is somewhat more streamlined and much more durable. Worth the small extra $$.
 
mark treidel;n1139554 said:
George, Mine is #14. It came with the tires you refer to. They were rubbing on the inside of the wheel pants and I did not want to 'grind off' the fiberglass inside so I switched to the tire above.
I do not like the 'trailer' tire flat profile for runway usage and they do present more drag as well. This tire is somewhat more streamlined and much more durable. Worth the small extra $$.

I also noticed that the "square" tires come really close to the wheel pants. I re-centered the the wheels by adjusting the axle spacers but they are still pretty close. I had to strike a balance between centering the tires in the pant and reducing available brake caliper travel.

Were the original wheels compatible with the scooter tires or did you have to do any other mod?
George
 
mark treidel;n1139552 said:
For safety, I would only run them with tubes on split wheels.

Hi Mark. I'm curious about this statement. What makes the split wheels the safer application of these tires?
 
I also use Heidenau K-75 and didn't see any equal subsitute for reliability/cost. On a Calidus they serve 500+ hours on paved runways and most of these hours are training thus a lot of take-offs and landings many of which aren't perfect.
For a Calidus' nose wheel I choose Aero Classic 4.00-4 tire which serves already over 700 hours in 5 years at one of machines.
 
mark treidel;n1139552 said:
These are the tires Abid uses for the AR-1. They are resilient, not low speed restricted and wear well. Since they are made for 'street use', they last for runway surface usage (which I use exclusively). For safety, I would only run them with tubes on split wheels.
Had them 1.5 yrs. and still have some 'molding nubs' and about 3/4 tread left.

What is the inflation max, and load max on these? Don't seem to show that on the page.
 
Joe Pires;n1139574 said:
What is the inflation max, and load max on these? Don't seem to show that on the page.

The inflation max will be determined mostly by your type of rim.
The Azuza rims are only like 30psi.
I have a similar set on my Scooter and are rated for 250 kilograms, around 5 hundred and some pounds per tire.
 
Wheels and tires each have a max inflation. My old plastic nose wheel had 20 lbs max, while the old tire was 50 psi. I now have an Azusa steel wheel and they said 50 lb air pressure is fine. The load on the new tire is 350, so maybe I will try those next.
 
Joe,

Max speed and load is in tire's designation - K75. "K" stands for speed up to 67 kmh, "75" stands for 387 kg (853 lbs). Here is the table for different other markings: https://www.webbikeworld.com/motorcy...e-information/
Max inflation is usually stamped on a tire. I use to use 1.8 - 2.2 bar (26 - 32 psi) depending on take-off weight, airstrip type and current flight task (for starter students it has sense to keep pressure a bit lower expecting their touch-downs would be far from ideal sometimes).
 
twistair;n1139593 said:
Joe,

Max speed and load is in tire's designation - K75. "K" stands for speed up to 67 kmh, "75" stands for 387 kg (853 lbs). Here is the table for different other markings: https://www.webbikeworld.com/motorcy...e-information/
Max inflation is usually stamped on a tire. I use to use 1.8 - 2.2 bar (26 - 32 psi) depending on take-off weight, airstrip type and current flight task (for starter students it has sense to keep pressure a bit lower expecting their touch-downs would be far from ideal sometimes).

Thank you!
 
Brian,
My suggestion about using tubes is simply to prevent any leakage via bad wheel rim seal and the sidewall. Split rims can be used w/o tubes but tubes are more of an 'insurance policy'.
In my climate, large temperature variation also affects tire pressure. Also (more so in trikes) there is a somewhat angled touchdown which puts the pressure against the sidewall on landing
which of course can loosen the seal over time; especially on bias ply (flat surface) tires. Basically, this is a matter of personal preference, and this is mine. I simply feel safer knowing they are there and I'm sure I've avoided a few flats because of them...lots of stickers, etc. I use 35#'s of pressure in the mains on my machine and 25#'s in the nosewheel. I prefer them stiffer as they roll easier.
I also inflate them with nitrogen which is not altitude/climate sensitive to pressure loss like air is.
George:
I did not have to do any centering adjustments with the K75 tire; it was just a minute bit thinner so as not to rub against the wheel pant surface. Nor did I have to change the travel on the calipers. No modifications were required; just the tire change.
 
Thank you, Mark. I wasn't thinking of them in the context of split rims and tubeless tires. Not having examined the split rims up close and personal yet I wouldn't have thought they would meet with such precision as to hold air in a tubeless configuration.

mark treidel;n1139608 said:
I also inflate them with nitrogen which is not altitude/climate sensitive to pressure loss like air is.

Now I have learned something new and interesting. I'm not sure how nitrogen can be immune to such things since "air" is roughly 80% nitrogen if memory serves. Will do some further reading.
 
Brian Jackson;n1139615 said:
Thank you, Mark. I wasn't thinking of them in the context of split rims and tubeless tires. Not having examined the split rims up close and personal yet I wouldn't have thought they would meet with such precision as to hold air in a tubeless configuration.



Now I have learned something new and interesting. I'm not sure how nitrogen can be immune to such things since "air" is roughly 80% nitrogen if memory serves. Will do some further reading.

Nitrogen is a larger solo molecule and is inert. It will not pass threw substrates as easily as ambient air. Most tire shops have a nitrogen fill station.
 
Brian Jackson;n1139633 said:
Thank you Jake. Amazing the interesting things that can be learned from the most benign questions.

No problem.
Since I am 1/1024th Scientist I know benign things !!!
 
I don’t entirely buy into this nitrogen thing. I know that the molecules are larger. Our atmosphere is 80% nitrogen. Why don’t the smaller oxygen (and other gases) molecules leak out first, leaving you with a higher concentration of nitrogen that increases every time you add air to the point where you have close to 100% nitrogen after a few air charges. I use nitrogen in air shocks because there is no moisture content in the nitrogen. But, is the moisture an issue inside a tire tube?
 
cesphil;n1139647 said:
I don’t entirely buy into this nitrogen thing. I know that the molecules are larger. Our atmosphere is 80% nitrogen. Why don’t the smaller oxygen (and other gases) molecules leak out first, leaving you with a higher concentration of nitrogen that increases every time you add air to the point where you have close to 100% nitrogen after a few air charges. I use nitrogen in air shocks because there is no moisture content in the nitrogen. But, is the moisture an issue inside a tire tube?

I've read some articles about the subject and all them agree that filling your tires with nitrogen is no more than pumping extra cash out of untutored customer. Yes, nitrogen molecule has larger diameter than oxygen molecule. They are whole 6% larger =) Thus this gives no profit. Moisture and dust in vulgar air also don't play much for tubes and tires but if one is worry then it's easy to use compressed air after filtering it.
 
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