GT Aggressor Comp 27.5 (650B)

agressor0101GT AGGRESSOR COMP 27.5 (650b)

This is my third bike purchase this year and is the result of the winter approaching.  I was looking for a cheap MTB style bike but mainly for road use as well as gravel and packed dirt tracks, wet and dry.  I definitely wasn’t looking for a full on MTB, not interested in off-road climbs nor downhill madness. I also wanted cheap as this will be my main winter rat-bike.

Various reviews pointed me towards this GT model and I found that it was available on Wiggle for not much money even when delivered to Switzerland.  I knew that I’d be really lucky to find a bike that was already set up for my needs but this comes pretty close.

MODEL2015 GT Aggressor Comp 27.5" (650b)
FRAMENEW 6061-T6 Aluminum Triple Triangle™ Frame w/Replaceable Derailleur Hanger Disc Brake Mounts and 1 1/8" Head Tube
FORKSR Suntour XCT HLO w/80mm Travel QR w/ Lockout FOR 27.5
CRANKSETForged Alloy 42/34/24T
BOTTOM BRACKETCartridge Sealed
PEDALSGT Slim Line Flat Pedal
DERAILLEUR(F) Shimano Tourney
DERAILLEUR(R) New Shimano Altus RD-M280
SHIFTERSShimano EF-51 EZ Fire Plus 7 Speed
REAR COGSSunrace 7-Speed 14-34T F/W
RIMSJalco JD200 Double Wall w/GSW 32H 27.5
TIRESAll Terrain 27.5X2.10" F/R
HUBS(F) Alloy Disc QR (R) Alloy Cassette Disc QR
SPOKES14G Stainless
BRAKESTektro MD-M300 Mechanical Disc w/160mm Rotor F/R
STEMAlloy Ahead
GRIPSGT Wing w/Waffle
HEADSET1 1/8" Ahead
SEAT POSTAlloy Micro Adjust


mtb_pedalsThe bike came with some quite large flat pedals that didn’t feel right and anyway could not be used with my mtb shoes that have clips from the BMC AC01 days.  A pair of Shimao MTB PD-M324 pedals with clips solved that one.  They come without reflectors but the old pedals had removable reflectors that slipped right onto these ones.  The nice thing about these pedals is that they are reversible so can also be used with trainers for a quick trip down to the shops.

agressor002agressor003 Next up I wanted a pair of mudguards to keep the worst of the wet off.  These Defender M3/33 set fit the bill really well.

The front section is fitted by inserting an expander into the steering post and simply tightening until it hold fast.  The blade is removable without removing the whole assembly so cleaning is a doddle.  It doesn’t move around much even when it’s windy.

The rear mudguard attaches to the seat post with a Velcro ratchet affair which didn’t look up to much but actually does the job really well.The angle and height is adjustable so you can experiment with the best position.  Although not quite as easy as the slip on front blade, the rear can also be removed quickly for cleaning.  Overall, I’d recommend these mudguards but if you are a true MTB type then maybe they could be a bit too fragile.

The bike came with knobbly tyres and it was apparent that these weren’t designed for my purpose so off they came and on went a pair of Big Ben MTB Road tyres from Schwalbe. You can see the tread in the mudguards pictures above.  Verdict is very grippy on wet or dry roads and excellent on dirt, gravel, and mud.


On the BMC I had hydraulic disk brakes.  At the time I thought it was tech for tech’s sake and this bike has confirmed that suspicion.  The disk brakes fitted on the Aggressor are cable operated but imo actually give more feel and control.  Cheaper to maintain and easier to repair too.

agressor004 agressor005









Power is provided via a triple crank set with 43/34/24 teeth shifted with a Shimano Tourney derailleur.  It’s a good solid piece of kit and the changes are very smooth.  The derailleur is banded on to allow for those downhillers to crash and wreck their bits and pieces without destroying the whole frame.

The rear end has a 14-34 cassette with the 34 being a super low hill climbing gear.  I’m pretty sure it could go vertical when combined with the smallest crank.


Shifting is via the superb Shimano Altus derailleurwhich is used on so many MTBs and hybrid bikes it must be one of the most common components out there.  Again the mounting is replacable so no worries about destroying the frame with a small crash.  The Shimano EF51 EZfire shifters are a dream to operate even with winter gloves.  They are fast and smooth – what more could you want.



Also on the handlebar I mounted a holder for the Wahoo Reflex Display.

The bike rides really nicely and 25 kmph is easily achieved on the flat over tarmac or less forgiving surfaces.  Comfort is average, the saddle might need to go, but a ride of just under 100km didn’t leave any lasting damage to soft bits.

Final words, if you are looking for a solid, reliable, well spec’d bike for the winter then you might want to take a look at this.