A single individual can register multiple riders during the registration process. All slots will be paid for with a single payment method at the end.
Generally it takes about 2 minutes to input an addt'l rider. So including yourself & 3 others, about 10 min total. Pretty safe bet you'll get spots but understand every delay drops your chances. More than that & we'd recommend splitting the duty with another.
Just because you're on the site & inputting rider data doesn't mean your spot is locked - that doesn't happen til the payment is processed successfully. It's possible that the ride can sell out while you're typing in all 20 names from your group - this HAS happened and it's a SERIOUS disappointment.
Two things to speed you up - first, open a user account at BikeReg.com with your data saved. Second, collect the below info from your buddies & have it ready to go. You can always edit info after registration thru BikeReg, everything except name and trip #.
The info we need most from each rider is name, a working email address they'll actually check often and their mobile phone number (what they might carry when in the field). WE ABSOLUTELY NEED THEIR EMAIL ADDRESS!