Oh, how I've agonized over this one. We're not a car-free family, so we have the option of driving, but I really prefer to bike at this point, and since so many of our outings are by bike, I've been chomping at the bit to let our infant Luc in on the "bike fun".
Just to be clear - most of the injury prevention crowd and cycling mainstream would say "no go" to babies on bikes. But people do it anyway, so here is my opinion how how a motivated and risk-aware parent might go about this. If done carefully it would seem to be not so different from a jogging stroller. For both bike and jogging stroller, however, it's probably wise to wait until at least 3-6 months. That said - how long did I last? 7 weeks. Your risk assessment may vary ... I do count myself as certifiably family-bike-crazy.
The primary concern with an infant is the bobble-head issue. Infants do not have appropriate musculature to support their relatively large heads, and thus cannot mitigate jostling and impact forces the way we can. There is also some concern about unrecognized repeated minor head injury from shaking and subtle impacts, as well as stresses on their necks. They of course, cannot communicate specific discomforts the ways toddlers can, so it’s hard to know if those are being missed.
So how can we minimize these risks, besides waiting until they're one year old and can sit steadily upright before taking them by bike? Amidships position in between the wheels (to reduce travel from impacts from front and back wheels), placement as low as possible to reduce rotational momentum with tipovers, a bike with a flexy steel frame and big tires run at low pressure, use of a well-secured rear-facing standard car seat, and a position where neither driver nor bike can land on baby all seem important.
The best way I've seen to accomplish this is with a car seat mounted rear-facing in the wooden box of a Dutch bakfiets or similar bike. This placement is low and centered between the wheels of this long bike, which minimizes up and down movement from bumps, and makes tipovers less scary. The wooden box affords extra protection, and the bike itself is not known for its speed. Plus, the baby is facing the rider, so it's easy to monitor jostling and comfort, as well as interact.
Sure, a bakfiets is expensive, but if you don't live in a very hilly area it'll be an ideal young kid carrier from baby number one up through multiple toddlers and preschoolers. Failing that, eager parents in the US often use infant adapters in bike trailers, which do worry me in terms of a lot of jostling (placement right over the axle), debris coming off the rear tire, and tipover potential. The bike trailer companies do market various infant slings and infant seat adapters, but are careful to specify that these are for strolling, not biking. From feedback I've heard, the slings may do a better job than the infant seat adapters with head pads and body wraps, as slumping forward in the seat seems to occur with the latter.
With our youngest I did end up going the trailer route, but instead of an infant adapter, I mounted a car seat base in the trailer for click in click out convenience, which was handy because Luc falls asleep instantly when we bike. It's soporrrific! In fact, when I'm desperate to help him nap, I go for a quick ride. A padded body/head support (the Snuzzler, see also the Cradler) helps prevent jostling in the seat. I keep the trailer tire pressures very low for extra suspension (better trailers have built-in suspension), use fenders and the front vinyl window to keep debris out of his eyes, stay on quiet smooth streets and trails, and am paranoid about my speed and around bumps.
So what's next? I'm working on a custom seat where he sits rear-facing (car-seat style) low-down in our MADSEN bucket, strapped in using the Chariot baby supporter for head/neck padding and secure harness. He'll be protected on three sides by the bucket and padding, and will be rear-facing (safer) but also facing Drew on the back bench (fun, not always safe depending on her mood). UPDATE: Done, and we love it!
Other options that could work but are hard to come by would include a car seat in cargo trike, like this Christiania (click for cute photo). The upcoming Taga convertible trike/stroller also seems to have an infant option. The Stouts in Colorado have come up with the coziest way to ride in the winter.
An option to avoid which you'll see if you read enough about Dutch biking is the front or rear-rack car seat adaptor. Read this test report to see why that's not a good idea. Other options to avoid are detailed in our April 1st post on "Baby on Bike Breakthroughs" ...
But what about the helmet? After all, in the US, bike safety often seems to begin and end with "wear a helmet". In these infant-on-bike options, my humble opinion is that a helmet would likely do more harm than good, since it adds weight to the head, pushes the head forward, introduces strap/airway concerns, and is designed for linear impacts and falls that just shouldn't happen in these setups. That said, if you're trying to comply with local laws, you might look at this.
So there you have it - my baby on bike confession, and a year's worth of ruminating on this topic. What do you think? Is biking with babies a selfish thing for crazed parents with self-reinforcing bike obsessions to do? Or is it our culture of fear and high-anxiety parenting that has had me in such a lather about such pursuits? I'm not sure myself, sometimes. Where would you draw the line? What has worked for you? Go ahead, out yourself in the comments ...