Mauvile city at the bike shop.
Yes
use a mach bike
Mach Bike Section of the Safari Zone
The Mach Bike is faster than the Acro Bike, and the Mach Bike allows you to go up slippery muddly slopes whereas the Acro Bike doesn't. Also, although you can ride the cycle path on an Acro, you can only set a record speed on a Mach Bike, because the Acro is much slower/easier to manouvre.
Use your mach bike and zoom past them.
You have to use a mach bike
There's a bike shop in the city with the electric gym. Go inside, talk to the shop owner and choose your bike (mach or acro).
If in ruby, sapphire or emerald get a mach bike and go to sky pillar. you can not get it in fire red or leaf green
The Acro and Mach bikes are only in Ruby, Sapphire and Emerald. There's only one bike in Crystal and you can get it in Goldenrod
Rayquaza is in Sky Pillar, you'll need a Pokemon that knows surf to there, and also the mach bike.
Mauvile, You cant get an acro bike and a mach bike. i tried.
Go to Mauville city and enter the yellow store with lots of bikes around it. Then, talk to the guy with the brown hair and he will give you the Acro bike, if you have the Mach bike already. ( He will trade bikes) ;) Pielover88;)