Aero Helmet fit

um i dunno, but apparently i fit into a extra small motorcycle helmet when i should have purchased a small or medium.  These helmets have adjusters, correct??  They have to be able to accomidate an extra .25 cm right?  I mean, where else would females be able to put their hair??

There's some overlap - get the Medium to be safe.  I have a Louis garneau Prologue size medium and my head measurement is somewhere in the 57 range and I am right in the middle of the adjustment range.

O and i'm getting it used, at a good price, and its a small.   SO i just wanna make sure it will fit me

The words "used" and helmet scare me... Aero helmets may be somewhat different as mostly used for races, but hope you know the owner etc. IMHO, there are few things I wouldn't mind buying second hand, but a helmet would have me thinking twice.

Good luck

Why would you think twice about buying a helmet???  its not like it just "goes bad".  If someone crashed in it, it would be quite obvious....

(a)  Yes, some helmets DO 'go bad'.  The materials that they are made of deterioriate over time, even with zero impacts.

(b) Not all damage to a helmet is obvious on inspection.  The material can get cracked or otherwise compromised without obvious visual evidence.

I'm not saying that every used helmet is a death-trap, but what you say here is wrong.  Read the info on helmet standards (CPSC, SNELL, ANSI, etc.) for details.

i have read them before, but not too in depth.  The helmet is very lightly used.

So back onto the origional discussion....  Will an extra 1/4cm make the helmet not fit correctly?