What would be the biggest upgrade on a mountain bike?

Question

I have an Ironhorse Azure Sport Mountain bike with decent components, over the winter I plan on making a few upgrades and was wondering what do experts or fellow bikers suggest as far as what upgrades would drastically improve the weight and performance the most... I ride 1-2 times a week on fairly technical trails...

fork?

derailleurs?

crank?

shifters?

Here are my specs:

Frame: 3.5” Travel Aluminum dw-link XC Race Frame

Brakes: Avid BB-5 Mechanical w/ 6” rotor

Levers: Avid FR-5

Pedals: Crank Brothers Smarty, Clipless

Rear Shock: Fox Float R Air, 6.5” x 1.5”

Crankset: FSA Alpha Drive, 44/32/22T Alloy/Steel

Headset: FSA Orbit Z, Zero Stack

Bottom Bracket: FSA Powerdrive w/ Alloy cups

Wheelset: Hubs: Alloy 32H w/ front disc; Rims: WTB Speed Disc

Fork: Marzocchi MZ Super Comp w/ Alloy steerer, 100mm Travel

Tires: Maxxis Crossmark; Front: 2.1”; Rear: 1.95”

Grips/Tape: NA

Handlebar: Ritchey OE Rizer, 31.8mm clamp

Seatpost: Ritchey OE Singlebolt, 27.2mm

Stem: Ritchey OE V2, 31.8mm clamp

Chain: SRAM PC-951

Cassette: SRAM PG-950, 11/34T, 9-speed

Rear Derailleur: Shimano Deore

Shifters: Shimano Deore

Front Derailleur: Shimano Deore

Saddle: WTB Rocket V Comp

Thanks in advance!

Answer 1

First...  is there anything worn down an needs replacing?  Check the chain and grip on tires.  Has the bike been tuned up and bearing repacked?  How are the teeth in your rings?

First fix anything that needs to be fixed, then decide.  I would upgrade derailleurs first.

Answer 2

i would say the fork or the rear shock but if plan on replacing a lot i would justv buy a new bike

Answer 3

Yeah, I would also replace and upgrade everything that is worn first, like the other answerer said.  Then upgrade your derailleurs and shifters to Shimano XT, or better.  Deore is a little bulky and doesn't perform as well as XT.  Then, to lose weight, the best places are parts that spin, most notably, your wheels.  They are spendy, but light, strong wheels make a big difference in spin weight.  You already have light tires, consider tubless, or lightweight tubes.  You don't say what brand you are running, but Mavic, DT Swiss, and Olympic rims are good ones to consider.  Likewise, your cranks could probably be lighter. You have light pedals, but I like the performance of  Shimano XT pedals better than Crank Bros.  More spin weight-loss: Shimano XTR cassette and chanrings.  More performance: while Avid makes excellent brakes,  I like the performance of hydraulics better: more control, less skid.  Magura, Shimano.  You can upgrade these at the same time as your shifters.  Consider the Shimano dual-control system with a rapid-rise derailleur in the rear.  I was skeptical about having my brake levers be my shifters at the same time.  But now I wouldn't go back to thumb shifters.