ChristinaChi wrote:In my opinion the most important thing when choosing a bike is choosing the corresponding weight and size which will fit your proportions perfectly.
I agree completely with Christina's comment on bike fit - if the bike is a poor fit it doesn't matter how light or how good of a "deal" it was. A poor fitting bike will be slow and/or will handle badly. Other key considerations brought up at various times in this thread:
1. Suspension? Great if one regularly encounters severe washboard or if the gravel roads are more like jeep trails (aka dual track mountain biking). But suspension adds to the cost and weight while also using your energy. Also, suspension is almost exclusive to mountain bikes which means flat bars instead of drop bars. Put another way, you'll be slower but more comfortable. :-)
2. Handlebar type? There are two basic types: traditional road style drops or flat bars used on mountain bikes. Yes yes I know there are many variations of each but in selecting drop or flat one likely will also will be choosing how the bike was targeted to be ridden: smoother paved and graded roads, or more for off road and harsher conditions. This in turn will show up with the size and type of tire, brake type, gearing, and more.
3. Tire size and clearance? Some of the new gravel bikes barely have room for 30c (1-1/8th inch wide) tires while others will fit a 48c (1.9") or wider (Salsa's Fargo for example).
4. Brake type? Lots of pro's and con's in the disk versus rim brake. It's a religious discussion I'm not going to touch. Both can be setup to work well and both can fail. The same for cable versus hydraulic.
5. Hub and axle type? The latest/greatest wheels have through axles as opposed to the hollow axle with quick release. The through axles were first used for suspension forks as they make a wheel and bike structure which is stronger, more rigid and will provide better control. Through axles are now used for rear suspension (same reason) and are migrating to high performance gravel and CX bikes. The standard axles with quick releases have worked fine for decades so if your riding won't include extreme mountain biking or racing, there's no "need" for the through axles. More and more of the high end bikes are getting through axles. Additionally mountain bike rear hubs are getting wider. The old standard of 135mm is being replaced with 142mm (Specialized and others) and the "Boost" 148mm width. Wheels build on wider hubs are stronger laterally (side-to-side).
The more mountain-bike-like a bicycle is, the more likely it'll have disk brakes, through axles and boost spacing.
6. Frame and fork material? Carbon is lightest and most expensive. Titanium and stainless steel are nearly as expensive, heavier but much more resilient in a crash. Aluminum and steel are the least expensive. In a crash carbon can shatter leaving one on the side of the road with a unrideable tangle of cables and bike parts. Yup, I've witnessed this. I've also observed badly damaged steel and aluminum bikes which were rideable - not necessarily "safe" but the rider was able to continue at a slow speed. There's lots of religion on which material is "best", but all can be used to make an excellent bike but a poorly designed and manufactured bike is going to suck regardless of the material. I own bikes built from all of the above and can observe many of the pro's/con's. I wouldn't hesitate to get an aluminum or steel bike for long distance gravel riding, but for a hilly cyclocross or road race I'd go for a carbon fiber thoroughbred which would be many pounds lighter. FWIW - a light weight carbon frame and fork will weigh about 3 pounds. A good quality steel frame and fork about 7 pounds. Put the same parts on both bikes and you've got a 4 pound difference for the entire bike. Throw me on the bike with a couple water bottles, some basic gear, and the total weight difference is just under 2% - so small it only matters if you're racing.
7. Gearing? An old (vintage?) 3x7 setup (triple crankset and 7 cogs in back) from an old mountain bike can work just fine if the gears are selected carefully. Conversely I've seen successful gravel racers on bikes with a 1x10 drivetrain. The latest/greatest top end drivetrains are 1x11. My preference is a 2x10 or 3x9 where my cassette ranges from 11-to-28 or 11-to-32. If riding on relatively smooth and predictable roads I prefer closer spaced gears. For mountainous terrain I prefer wider gears with a greater overall range. For a first bike I'd suggest a wider range, such as a 3x9 or 3x10, and then adjust to find what works best.
8 Frame type: Road/Touring/Cyclocross/Gravel/Adventure/Mountain? I tried to list in ascending order of weigh and rigidity, but depending upon the manufacturer and marketing for that company some of the types may move around a bit. In short, gravel bikes span a wide range from road bikes with slightly wider tires to mountain bikes with drop bars. Bikes that are more "road like" will be lighter and faster but will be more challenging on roads with mud, washboard and deep sand/gravel. Wider tires help A LOT in softer conditions. Mountain bike frames are stiffer and more durable, but they weigh more and transmit more shock and vibration to the rider which over time will tire the rider - this is one of the reason long distance randonneur riders prefer road frames with wider tires than would be used by racers. Also note that the geometry of a road bike is very different than a mountain bike and this will show up when climbing, descending and when in technical conditions (sand, gravel, etc etc). My preferred bike has 700x40c tires. For faster rides I'll go for 700x35c tires and for more challenging terrain I'll ride another bike with 26"x2.25" semi-slick tires.
9. Attachment points? If you plan to have fenders or racks, make sure the bike has the proper mounting points. Few high end light weight race bikes are setup for adding fenders or a rack. Adventure touring bikes (Salsa Fargo for example) have attachments for front and rear racks, fenders, 3 water bottles, I'm probably missing other options...
So after all this, you wonder which bike should I start with? If there's a group you're planning to ride with, find out what they're riding and get something similar. If it's not setup well for the terrain (roads) then you'll all suffer through together (misery loves company?). Put another way, you won't be at a disadvantage to the rest of the group. Over time you'll certainly make adjustments (tire width, gearing, lighter or stronger wheels, etc etc) but these are best made after you've been out and have many rides. If you're not planning to ride with a group, then the choice is based on how the bike will be ridden (Mountains with long gradual climbs? Short but steep rolling hills? Mostly flat? Windy? Long 100+ mile rides? Commuting? Fenders? Bags for camping/touring? Other?).
One last thought - if you're in an area with a good selection of used bikes on Craigslist or other ad's, a used bike will depreciate slower than a new bike and it is possible can get a higher end bike for the same $$$ in the used market. It's also possible to pay too much or buy a bike with a major problem (cracked or broken frame, major components which are broken, etc). Saving $$$ on the bike will also allow some budget for a second set of wheels with a different width tire. This way one can have a set of road wheels with 700x28c tires, and gravel wheels with 700x40c tires and a cassette with lower/wider gears.
Happy shopping!
