I'm a roadie and don't know much about mountain bikes, but need to get one for my son. The last mountain bike I purchased was a Specialized FSR Pro in 2000 for $2k, so it's been a while. My son is 10, but tall for his age, he is all leg and grows like a weed. I sized him up on some size small adult bikes and it looked a little big, but in a couple months it should fit and grow with him. LBS guy agreed.

Looking at a couple entry level bikes. I can get the Diamondback Overdrive Sport for $350 (pro deal), but it is a 29er. They did not have this in the local LBS, but he stood over a Response and it was fine. Thoughts on the difference of a 29er vs. 26 for him?

Alternatively, I am looking at the BAMF Full Nelson. Seems like a decent bike for the same price.

The specs follow for each bike. Thanks in advance.

Diamondback specs
Frame:Overdrive 29'er Butted 6061-T6 Aluminum w/ Formed Top / Down Tube, machined headtube, forged drop outs w/replaceable hanger, disc only
Rear Shock:N/A
Fork:SR Suntour XCR-LO 29 100mm travel, 30mm stanchions
Headset:Integrated FSA Drop-in ACB upper, Zero Stack lower internal cup and cartridge bearing, 1 1/8"
Cranks:SRAM S600 w/ replaceable rings, 42/32/22t
Bottom Bracket:Sealed Cartridge
Front Derailleur:Shimano Acera dual pull, top swing 34.9
Rear Derailleur:Shimano Acera 8spd
Shifter:Shimano SL-M310 8spd Rapidfire
Cog Set:SRAM PG-820 8spd Cassette (11-32t)
Chain:KMC-Z82
Hub (F):32h SL-7 Alloy w/ CNC Disc Mount
Hub (R):32h SL-7 Alloy Cassette w/ CNC Disc mount
Spokes:Black 14g Stainless Steel
Rims:32h Weinmann SL-7 Doublewall
Tires:WTB Wolverine Comp 29x2.2
Brakes:Shimano BR-M395 Hydraulic Disc w/180mm frt / 160mm rear Rotors
Brake Levers:Shimano BR-M395 Hydraulic
Pedals:Wellgo Alloy forged, CNC MTB
HandlebarB Lazer Series 31.8mm low rise
GripsB4L 135mm Kraton
StemB AL6061 Ahead 7 31.8mm
SeatB Race saddle
SeatpostB Lazer Series Micro Adjust 30.9mm
ExtrasB Key Chain, Owners manual, H20 bottle mounts, Chainstay Protector, Clear Coat, 3 extra inches of wheel diameter!

BAMF specs.

  • BAMF Bad Ass 6061 Custom Aluminum 26 Frame
  • RST Capa Suspension Fork
  • Bengal Mechanical Disc Brakes
  • SRAM X.4 Rear Derailleur
  • SRAM 3.0 Front Derailleur
  • SRAM X.4 Trigger Shifters
  • Weinmann X-Star 18 Disc Rims and WTB 26x1.95 Kenda Tires
  • SuntourXCT-V2 42/32/22 Crankset
  • BAMF Handlebars, Stem and Seatpost
  • BAMF MTB sadd