A few weeks ago I crashed while in a line (drafting) and cracked my helmet.  I had a relatively inexpensive Giro Havoc helmet, which is the second from the bottom of the mountain bike helmets on the Giro.com site.  Before I started training for the Ironman, I hadn’t road biked since high school so, I wasn’t sure whether I should purchase a road bike helmet or a mountain bike helmet. (Will I go back to only mountain biking once the race is over?)  It turns out that the only difference between the two is in whether there is a visor or not.  Mountain bike helmets have visors, road bike helmets do not.  This is amazing to me since you could always just remove the visor (yes, you can just remove the visor from a mountain bike helmet).  REI disagrees this assessment with the statement, “Road bike helmets tend to stress lightness, ventilation and aerodynamic styling.”  However, the table below (which uses REI’s specs for weight because Giro.com doesn’t include weight ironically) shows this is not the case:

Note:

• The difference between the cheapest and the most expensive helmets in terms of weight was 5 grams (.18 oz) while the cost difference was $200.
• The $105 Monza road helmet was 20 grams (0.7 oz) lighter than the Ionos at $230.
• My Havoc mountain bike helmet is 6 grams (0.21) heavier than the $146 more expensive Ionos road helmet.
• The number of vents presumably is not a true indicator of much since the cheapest helmet has only one less vent than the most expensive and frequently (Havoc versus Ionos for example) cheaper models have more vents.  When it comes to vents, size is what matters, not quantity – and the difference is only significant in hot weather.
• It wouldn’t make sense for Giro.com to show helmet weights if they want to sell there most expensive models.
• All the Giro helmets in the sport/road/mountain category used in-mold construction.

Here are some other things I learned:

• All helmets are the same when it comes to safety.  To test helmets the drop them from various heights  onto an anvil.  In the end, “at the high end, you will still find big vents and high prices, but no verifiable advantage in impact performance. 
• Consumer reports bike helmet ratings
• “Carbon fiber use is still limited to premium models, limited by fiber price costs. It does allow lighter construction, but there is so little of it used in a bike helmet that the weight saved is minimal except in heavy BMX helmets.”
• I found http://www.helmets.org to be a good consumer oriented resource.

Sunday, June 15, 2008 5:35:24 AM (Pacific Standard Time, UTC-08:00)      Comments [2]  Personal | My Sports