“I just flew in and boy, are my arms tired!” is a very old joke (1940s). The arms are tired from flapping so much (like a bird’s wings). Transformers arms are actual tires, and there are jokes.
   
“I just flew back from the Transformers convention and boy are my arms tires” was posted on Twitter by Street Carnage on February 24, 2009. “I just flew back from a Transformers convention and boy are my arms tiires” was posted on Twitter by Street Carnage on May 20, 2009. “I just flew in from the Transformers convention, and boy are my arms tires” was posted on Reddit—Funny on January 21, 2011. “I just flew in from a Transformers convention. And boy my arms are tires” was posted on Reddit—Jokes on April 20, 2023.
   
 
Wikipedia: Transformers
Transformers is a media franchise produced by American toy company Hasbro and Japanese toy company Takara Tomy. It primarily follows the heroic Autobots and the villainous Decepticons, two alien robot factions at war that can transform into other forms, such as vehicles and animals. The franchise encompasses toys, animation, comic books, video games and films.
     
Twitter
Street Carnage
@Street_Carnage
I just flew back from the Transformers convention and boy are my arms tires.
1:57 PM · Feb 24, 2009
   
Twitter
Street Carnage
@Street_Carnage
I just flew back from a Transformers convention and boy are my arms tiires.
9:54 PM · May 20, 2009
   
Twitter
🌟 Kristina S. 🌟
@superpuppy
“I just flew back from a Transformers convention and boy are my arms tires.” http://is.gd/C5Kv (via @dfltr) - *snicker*
1:51 PM · May 21, 2009
   
Twitter
Tom Martin
@HeyChinaski
RT @dfltr: “I just flew back from a Transformers convention and boy are my arms tires.” http://is.gd/C5Kv
2:19 PM · May 21, 2009
     
Reddit—Funny
Posted by u/Spebt January 21, 2011
All the funniest jokes that you will ever need ever. Forever.
(...)
I just flew in from the Transformers convention, and boy are my arms tires.
 
Twitter
ex✨tee✨naw
@exteenaw
I just got back from a Transformers convention and boy my arms are tires. (stolen)
11:52 AM · Jan 29, 2011
     
Reddit—Funny
Posted by u/skrimyr February 24, 2011
I just flew in from the Transformers convention
Boy are my arms tires.
 
Twitter
最後の王の生活
@TaeKnows_LK
I Just Came From A Transformer’s Convention., And Boy My Arms Are “Tires” #ThatWasAJoke
8:09 PM · Jun 12, 2011
     
Reddiot—Jokes
Posted by u/fighterjet321 March 3, 2013
So i just came back from a transformers convention…
...and boy, are my arms tires!
   
Reddit—Jokes
Posted by u/Tech-Mechanic January 24, 2014
I just drove in from a Transformers convention…
... and boy, are my arms tires!
 
Twitter
Tetia LC
@CaseyTetia
@Splashscore #MadeToMake I just got in from the Transformers convention and, boy, my arms are tires!
2:35 PM · Mar 31, 2016
     
Twitter
BarVoter
@BarGamer
I just got in from a Transformers convention - itswalky: canderemy: aberjona: and boy are my arms tires…. https://tmblr.co/ZkrdIv2C9Db10
12:47 AM · Sep 16, 2016
   
Reddit—Jokes
Posted by u/DoniusLong October 7, 2018
Just got back from the Transformers convention
and boy are my arms tires.
 
Twitter
NotWittyGoth
@NotWittyGoth
Optimus Prime [doing standup]: “Good evening ladies and gents, I just flew in from New York and boy my arms are tires!”
5:30 AM · Feb 12, 2019
 
Reddit—Dadjokes
Posted by u/nwa747 October 29, 2020
I just flew in from a Transformers convention.
And boy my arms are tires.
     
Twitter
MimiLisa 2.0
@69MimiLisa
I just flew back from a Transformers convention…
And boy, my arms are tires.
8:52 AM · Mar 28, 2022
 
Reddit—Jokes
Posted by u/nwa747 April 20, 2023
I just flew in from a Transformers convention.
And boy my arms are tires.
 
Twitter
Derek 
@DerekNeverFails
I just flew in from a Transformers convention, and boy my arms are tires
7:02 PM · Apr 20, 2023