On both mountain and road bikes, the rear derailleur is a good place to spend money.
When you look over a new bike, you start to recognize the same names again and again -- Shimano, Campagnolo, SRAM, Avid, FSA and others. Most of the bikes lined up in your local shop are outfitted with components from the same handful of companies.
Even if there isn't a wide variety of component brands to choose from, each company offers a diverse mix of models that can greatly affect the price and performance of your bike. A SRAM rear derailleur might cost you $20, $250 or anything in between. Depending on your needs and your budget, finding the right mix of components can be key to landing the ideal ride.
How low can you go?
Everyone wants to save money, but when it comes to the cheapest components, you get what you pay for. Low-end bikes, particularly those sold at discount stores and sporting goods shops, often come with a jumble of no-name parts.
It's a gamble to go with a bike that doesn't have brand-name components. The parts may be clunky to use or not durable enough to last. Often, when low-end components fail, you can't service them and they must be replaced.
For novices and most occasional riders, a road bike with Shimano's Sora group or a mountain bike with SRAM's 3.0 parts are safe bets. If you plan to put in some regular miles on your road bike, bump up to Shimano Tiagra or Campagnolo's Mirage and Xenon groups. If you want to hit the trails with your mountain bike, try SRAM SX4 and SX5 or Shimano Deore and Alivio.
Middle of the road
While the average bike might work for the average American, most athletes demand more from their machines. Performance, durability and weight are important factors to people who use a bike for training.
But having a solid ride doesn't mean you have to use the same equipment as the pros. Most brands offer a level of components that strikes a good balance between cost and high-performance. These components can be considerably lighter than low-end parts, yet only slightly heavier than the most expensive options. They can be fine-tuned for improved accuracy and smoothness while being durable enough to last for years.
Mountain bikers can count on Shimano LX and XT components or SRAM X.7 and X.9. Serious roadies should consider Shimano 105 and Ultegra or Campy's Chorus or Centaur.
Nothing but the best
If you aspire to be like your two-wheeled heroes from the peloton, your local bike shop can set you up with a Tour de France-worthy ride -- but it comes at a price. When making the leap to top-end components, prices shoot up considerably. A Shimano XT rear derailleur might cost 50 percent more than the model just below it, the LX. However, Shimano's top-of the-line XTR derailleur could cost you nearly double the price of an XT.
In some cases, companies use materials such as carbon fiber and titanium to improve stiffness or shave weight. But these improvements in performance can be relatively small compared to the price hikes that come with them. Still, if you're the kind of athlete concerned about shaving minutes or even just seconds off your times, it could be worth it.
Mix and match
While some bikes are built with components from the same group-set, manufacturers will often mix them up. A bike could have a lightweight set of cranks, but just average brakes or two different levels of derailleurs. By prioritizing what components are most important, you can often improve the value of a bike.
Rear derailleurs are a good place to spend money. On a road bike, you want accurate shifts, while mountain bikers need derailleurs that can take a beating and still perform. Likewise, don't skimp on shifters. There are a lot of small moving parts that can break or wear out over hours of scrolling through gears. Cranks are an excellent place for competitive riders to shave weight and improve performance, as higher-end cranks use lighter and stiffer materials.
In brakes, poor performance is particularly noticeable in low-end models, while higher-quality brakes differentiate themselves more by weight savings. Compared to other components, you can compromise a bit on front derailleurs in favor of spending more on other parts.
Road components: The breakdown
Pro: Shimano Dura-Ace; Campagnolo Record; SRAM Force; FSA K-Force cranks
Competitive: Shimano Ultegra; Campagnolo Chorus; SRAM Rival; FSA SLK cranks
Serious Training: Shimano 105; Campagnolo Centaur or Veloce; FSA Energy or Gossamer cranks
Recreational: Shimano Tiagra; Campagnolo Mirage or Xenon
Novice: Shimano Sora
Mountain bike components: The breakdown
Pro: Shimano XTR; SRAM X.0 shifters and derailleurs; TruVativ Noir cranks; Avid Juicy Ultimate brakes
Competitive: Shimano XT; SRAM X.9 shifters and derailleurs; TruVativ Stylo cranks; Avid Juicy Seven brakes
Serious Training: Shimano LX; SRAM X.7; TruVativ FireX cranks; Avid Juicy Five brakes
Recreational: Shimano Deore or Alivio; SRAM SX5 or SX4; TruVativ Blaze cranks
Novice: Shimano Acera or Altus; SRAM 3.0