how fast can you change a tire?

because the boys in NASCAR pretty much revolutionized how it was done in a race setting..

http://www.nascar.com/news/120814/ups-air-guns/index.html

Somewhere in the development also came a very important step- making sure you don't cross thread the lugs. A very underrated development, IMHO.

It seems easier on tire lugs, since you can make the shaft fit the threads pretty closely, so that it's hard to cross them when the bolts are hanging on the end of the studs. (and remember, someone was smart enough to throw away the original nuts, and lightly glue the new ones to the wheels).

When I stated here 20 years ago, I was shown some specialty smaller bolts that the head was shaped funny- so that the nut could not be cross threaded. It was pretty cool.

Maybe not as important as the impact wrench use, or the 1-2 stroke jacks. But important.

another intersting thing I've read about- the single lug development. Of course races like NASCAR and Indy do a lot of work keeping the time to a minimum, and somewhere in the 80-90 range, someone figured out a single nut that didn't use 6 sideds, but a set of thin fingers that would slot into the socket instantly on a spinning impact wrench.

and in the 90's, Mercedes used to have fun with pit competitions between all of their major teams. Picture McLaren vs. Penske. At the time, F1 wasn't what it is today- even with all the people, it wasn't that fast. What McLaren noticed was that the single tire changers for Penske were really quick, which was mostly due to the fingered nut not needing lined up like the 6 sided nut used at the time in F1. Now tire changes became much easier, and more strategic. (note, I'm still not a big fan of the 3 person/corner tire change- that's lame. I'd rather see one per corner at the most, 2 for the whole car would be better.)

The nascar cars use a regular six sided nut with a fingered socket so you don't have to release the trigger going from nut to nut, the spining socket engages the nut and it has a spring to eject the nut which usually has a tefoln like coating so it doesn't get stuck in the socket.

Saw a change in this year's F1 Hungarian GP that was so fast it seemed like the car barely came to a complete stop I actually rewound to look at it a few times...crazy.

I was at a trade show with a presentation by one of the higher-ups at the Roush Nascar operation.

One thing he talked about that I would never have thought of is who they recruit for the pit crews.

They now go after former professional athletes; football players and such who have the physical and mental quickness and drive to perform. They train, practice, and travel like professional sports teams too.

I worked for a dealership which belonged to a well known name in the NA$CAR bidness and met a few of the retired pit guys. One told me they generally trained at least 20 hours a week.

On the bike side of things like this, the ISDE (International Six Day Enduro) rules say the rider is the only person who can work on the bike during the event and they can use only the tools and parts they carry. They can't even have tools handed to them.

Lots of riders will do their best to get to a check early (unlike AMA rules, FIM does not penalize for being early) and that way they have a few minutes to do maintenance before they start the next section. At the end of the day, they have (IIRC) 2 hours in parc ferme to do major repairs, so those guys have gotten pretty good. Oh, and the engine etc is sealed, if you fry a piston etc you are not allowed to replace it. You are out.

Changing a motorcycle tire? That's a slow aggravating PITA, right? The ISDE guys can do it in four minutes. That's from the time you flop it on the ground till the time you prod the kickstarter. I know this because I have actually watched it done.

Neat article about this subject: http://www.scribd.com/doc/64469990/5min-Motorcycle-Tire-Change

Five minutes is actually slow by ISDE standards. And this gal rode my club's enduro a couple of times, she hauls ASS in the woods.

Have you relocated the bead lock Curmudgeon to do it like the bike tire link describes? Other than possible balance problems, it seems like a good idea. Might try it.

No, I never did that kind of modification. Sounds like it makes good sense, though. I can still change a tire pretty quick, the other night I did a rear tire on a 750 Shadow in about 12 minutes (yes I time myself, competitive jerk that I am! ) I might have been able to do it faster if I could have laid it on its side but it ain't no dirt bike.

I was doing about 8-10 seconds per tire when we were practicing on the Kinetic GS M3. That is 5 lugs off, wheel off, new wheel on, 5 lugs back on.

In reply to DukeOfUndersteer: Color me impressed.

I change wheels at the pace of a glacier apparently.

I thought this was going to be putting new tires on a car. When I worked at NTB in college I could do eight tires per hour (two cars) from the time I touched the ticket until I hung it up for the salesman

My record is five minutes to mount and balance four tires, including new valve stems. Airing them up is glacial.

LainfordExpress wrote: I thought this was going to be putting new tires on a car. When I worked at NTB in college I could do eight tires per hour (two cars) from the time I touched the ticket until I hung it up for the salesman

i've seen stories about the people behind the scenes in the NASCAR garage that mount and balance all the tires for the teams during the race weekend and even during the race.. they knock them out pretty damn fast. it must be the old style tire changers they use- they don't use the kind that clamps onto the rim and spins it around, they use the kind with the center post that you lay the rim onto with the spinning tire iron of death on it.. ..

I was pretty fast back in the day, can't remember my fastest time. I was the only tire changer in a very busy tire shop with five bays. They had two mechanics that wouldn't touch a tire. That lasted for about a month before I got fed up and made them hire me some help.