Carrying the items needed for the day often requires panniers, and panniers need to be mounted to a pannier rack.
Four-point fixing vs three-point fixing
Racks are designed to fasten to the frame either at four points or three. Four-point is stronger. Four-point means the rack attaches to each of the dropouts and each of the seat stays. Three-point racks have a single fixing at the brake bridge. They can be a useful on a road bike.
Fastening the bottom of the rack
Most bikes have threaded eyelets brazed onto the dropouts, to accept screws. Some bikes have two sets of eyelets, one for a mudguard, the other for a rack. Other bikes have just one set of eyelets, meaning the mudguard and rack need to be fixed using the same bolts.
Some racks are designed to fasten to the wheel spindle. These do not need to be fastened to eyelets on the bike frame but they make wheel removal complicated. This is a common arrangement on Dutch bikes.
Fastening the front of a rack to a frame with no braze-ons
P-clips can be used to attach a rack to stays without threaded braze-ons although this is generally less rigid than mounting to braze-ons. P-clips should not be used to support the bottom of the rack.
Depending on the geometry of the bike frame, it may be possible to fasten the rack to the top of the seat tube instead of the seat stays. Attaching the rack to the top of the seat tube works very well on bikes with short seat tubes and vee-brakes, where the vee-brake gets in the way. It’s also a good solution for a mono stay. Seat tube collars with bosses are available. They are a direct replacement for a standard seat tube collar.
Features to look for in a pannier rack
- Dual rails
Some racks are made with with additional horizontal rails a few centimetres below the rack top. Your pannier hooks go on these lower rails. With this design, the top of the rack can be loaded and unloaded independently of the sides. This is useful if you use a rack pack in conjunction with panniers, because it allows you to fit or remove the bags in any order. The lower rail also positions the panniers lower to the ground, which improves stability. An example of a rack with dual rails is the Tortec Expedition.
- Offset rear stays
Some pannier racks are designed with additional metal at the rear in the shape of a dog’s leg. This stop the rear portion of a bag from swinging into the wheel. This is particularly useful with soft or flexible bags which can move when loaded.
- Light mount point
Most battery lights are supplied with seatpost brackets. However, luggage on top of a rack can obscure the seatpost, blocking the rear light from view. The solution is to mount the light on the rack, and this is easiest on a rack with an integrated light fixing point. Read more.
Other types of rack
Low riders (pictured right) allow smaller panniers to be carried on the fork. Some designs mount with clamps, others fit with screws to bosses.
Beam racks clamp to the seat post and nowhere else. They were developed for bikes with rear suspension, where a conventional rack would fix the stays to the seat post, locking out the rear suspension as a consequence. Beam racks are limited to carrying rack packs and other small items; they cannot support panniers because the beam is too flexible.
- A CTC forum thread with ideas on how to attach mudguards to rack rather than frame.