Did you just buy your first mountain bike so you can get into XC racing?
Chances are you bought something like the Trek 6700, Giant XTC 1, Cannondale F4, or Specialized Rockhopper Expert. These are roughly $1100-1300 bikes, which is not cheap, but you still might want to upgrade some parts and add accessories to decrease the weight and improve the performance.
Here is what I would do to make your bike race-ready without spending too much money:
Day of Purchase
The first upgrade you need to make is going to clipless pedals. You should do this immediately, because it’s a huge performance upgrade!
Most bikes in this price range either have flat pedals, no pedals at all, or maybe the basic Shimano SPD pedals. (If they do come with a pedal like the Shimano M520, you can use that to start, but be prepared to upgrade eventually, as these pedals don’t always work well.)
If the bike comes without clipless pedals, I would recommend looking at nicer pedals from Shimano, Time, and Crank Brothers. Popular models are the Shimano M770, Time ATAC XS Carbon, Crank Bros Eggbeater SL, and Crank Bros Candy SL.
You will also need special shoes to go with the clipless pedals. Take a look at models from Shimano, Sidi, Northwave, Specialized, Bontrager, Diadora, and Pearl Izumi. (Consider some more cycling clothing while you’re at it.)
Next, look at the saddle. There’s a chance you’ll like the saddle that comes on the bike. If so, great.
You won’t be doing too many long rides where you sit the whole time (unlike on a road bike,) so the saddle won’t be as big of a deal. But if you hate the saddle, switch it! I’m a big fan of Fizik and WTB saddles for mountain bike use.
After A Few Rides
After a few rides, consider getting some new rubber. AKA, grips and tires.
If the stock grips are comfy, go ahead and stick with them. But if they suck (as a lot of grips do,) upgrade them. I think the Oury grips and ESI grips are good, but also try out the Ergon grips if you have had any hand discomfort with regular grips.
Next, tires. Even if you got decent tires on your bike, mountain bike racing calls for more than one pair of tires. That’s because you need at least two sets of tires – one for dry conditions and one for wet, muddy conditions.
Some tires I like include the IRC Serac XC, Maxxis Crossmark, Maxxis Monorail, Hutchinson Python, and Kenda Nevegal. But there are many tires out there, and you need the ones that match your typical riding conditions. (Someone in the Arizona desert needs different tires than someone riding technical East Coast singletrack.)
Ask the local bike shop or your fellow racers for tire recommendations for your area.
New Wheels, Go Tubeless
As you start thinking about new tires, also think about going tubeless. Switching to tubeless tires is a huge performance upgrade! (First priority for performance is clipless pedals and shoes, but a close second is tubeless tires.)
There are two ways to accomplish this – buy UST wheels, or use a Stan’s NoTubes conversion kit.
On a budget:
If you’re on a budget, go for the Stans NoTubes conversion, which will convert your existing wheels and tires to tubeless for just about $55.
Also, if your standard wheels are good quality and you don’t want to spend $650 on new ones, the Stan’s conversion kit is for you.
With a little work, you’ll turn your regular wheels into a sweet set of tubeless wheels! It is so worth it! (It takes some work though, so don’t expect it to be easy.)
If you can afford new wheels:
If you have the money, spring for some new wheels. These are typically called UST tubeless wheels, and two popular options are Mavic Crossmax SL and Stan’s Olympic Disc wheels.
Both wheelsets are fairly expensive (around $650-900,) but they are lightweight and don’t require fussing around to get them working without tubes.
Important Components to Upgrade
Here are some good ideas if you still have more money than you know what to do with:
Your brakes get a lot of use when mountain biking! These days, bikes in this price range come equipped with decent hydraulic disc brakes. These should work great for years to come, so don’t be in a hurry to upgrade.
On the other hand, if you have V-brakes, I’d swap those out ASAP. Disc brakes work so much better, especially in wet conditions, so it’s worth the investment.
But let’s say you have some basic hydraulic discs like the Avid Juicy 3 or Shimano Deore. They’re alright, but if you want better performance (nicer levers, better modulation, more power, etc.), you can upgrade your brakes because they are so important.
A popular option is the Avid Juicy Ultimate, but there are also nice brakes from Shimano XTR, Hayes, Hope, and Magura.
Another expensive upgrade, a nice fork could cost more than your wheels. (I feel wheels are much more important, and brakes a little more important than this upgrade, but a good fork is nice to have.)
The real key is to have a fork with a lockout. These days, virtually every fork is going to have a lockout, so your current fork is probably fine.
But you can save some serious weight and get a better feel with a nicer fork. The RockShox SID and Fox F100 forks are popular options.
A good drivetrain is essential to performance, but a basic drivetrain consisting of Shimano Deore and/or SLX parts (or SRAM X.7 or X.9 components) should deliver solid performance. (If your drivetrain isn’t performing well, consider adjusting it properly or working on your shifting technique.)
Considering the likelihood of damaging derailleurs while riding, I would just wait and replace them when necessary. (If you must upgrade, I’d stick with Shimano XT, as XTR is super expensive.)
As for the rest of the drivetrain, just replace it as necessary. When they need replacement, a good chain and cassette will improve performance and save weight. Your bike probably came with a cheap, heavy cassette. (That’s the #1 priority for upgrading if you upgrade anything in the drivetrain.)
Just remember that you’ll go through at least a couple chains each year, and the cassette will need changed every so often.
Other Bicycle Components
If you’ve made it this far, your bike is probably very nice. There’s not much left to upgrade, but here are a couple ideas:
To save weight, consider a carbon seatpost. You could also choose a carbon handlebar to save more weight and possibly increase your comfort.
But the seatpost, stem, and handlebar are probably the last parts I’d upgrade.
Final Thoughts on Upgrading Components
Upgrading components can be fun and exciting, but buying purely on emotion will burn through your money real fast. You should first upgrade the parts that will give you the most bang for your buck, and then move on to the other parts. And don’t forget that many parts will wear out and need replaced, so you want to have some money saved for that!
In any case, it’s your bike, so have fun with it!