Bronson Alloy 27.5" - AM - 150mm VPP Travel
- Frame: £1,599
- Custom Builds from £2,999
When we introduced Bronson, it took the market by storm, redefining what people expected from a 150mm trail bike.
Equally at home in the Trans-Provence as it was on The Ridge, updating and improving it was going to be no small feat.
The most visible upgrade is the completely new VPP® link arrangement. The lower link tucks neatly above the bottom bracket, fully-recessed and protected from impacts. Meanwhile the box-section upper link now mounts cleanly to the top- tube and enhances lateral stiffness as a result.
Shock rate’s been in refined in the process too, delivering greater small bump sensitivity and a more progressive mid-stroke.
Geometry has also evolved subtly to meet demand from riders for a bike of this ilk. The seat tube angle’s been steepened, placing the rider right above the cranks and perfectly in position to lay down the power. Meanwhile a one-degree slacker 66 degree head tube angle combines with a 20-25mm longer top tube and shorter chainstay length to create an evermore rally-ready geometry than its predecessor.
This CC-level carbon frame is every bit as stiff and strong as our C-level frame, but weighs about 280 grams less, due to the use of some lighter, stronger, and more expensive carbon fiber. Using this material in key places allowed us to use less material overall, which is what shaves off more than half a pound from the frame.
- 148mm Rear Axle Spacing
- 150mm (6") VPP™ suspension
- 27.5" wheels
- Double sealed pivots for long bearing life
- Angular contact bearings maximize stiffness
- Collet axle pivots lock in place without pinch bolts
- Bottle cage mount within front triangle fits piggyback shocks
- Molded rubber swingarm and downtube protection
- Stealth and external seatpost cable routing
- Threaded Bottom Bracket
- ISCG-05 tabs for chainguide compatibility
- Direct mount rear derailleur option
Shock: Fox Float Performance
|Rider Weight||Air Pressure||Shock Sag|
|100lbs (45.5kg)||100 psi||15-17 mm|
|120lbs (54.4kg)||125 psi||15-17 mm|
|140lbs (63.5kg)||150 psi||15-17 mm|
|160lbs (72.6kg)||175 psi||15-17 mm|
|180lbs (81.8kg)||200 psi||15-17 mm|
|200lbs (90.7kg)||225 psi||15-17 mm|
|220lbs (99.8kg)||250 psi||15-17 mm|
|240lbs (108.8kg)||275 psi||15-17 mm|
|260lbs (117.9kg)||300 psi||15-17 mm|
|280lbs (127kg)||325 psi||15-17 mm|
Shock: Fox Float X Factory
|Rider Weight||Air Pressure||Shock Sag|
|100lbs (45.5kg)||120 psi||15-17 mm|
|120lbs (54.4kg)||145 psi||15-17 mm|
|140lbs (63.5kg)||170 psi||15-17 mm|
|160lbs (72.6kg)||195 psi||15-17 mm|
|180lbs (81.8kg)||220 psi||15-17 mm|
|200lbs (90.7kg)||245 psi||15-17 mm|
|220lbs (99.8kg)||270 psi||15-17 mm|
|240lbs (108.8kg)||295 psi||15-17 mm|
|260lbs (117.9kg)||320 psi||15-17 mm|
|280lbs (127kg)||345 psi||15-17 mm|
All measurements reflect installation of a fork with a 544.4mm axle-to-crown height.
|Top Tube Length||573mm - 22.5"||596mm - 23.4"||618mm - 24.3"||651mm - 25.6"|
|Seat Tube Length||395mm - 15.5"||420mm - 16.5"||460mm - 18.1"||495mm - 19.5"|
|Head Tube Angle||66°||66°||66°||66°|
|Seat Tube Angle||74°||74°||74°||74°|
|BB Height||341mm - 13.4"||341mm - 13.4"||341mm - 13.4"||341mm - 13.4"|
|Wheelbase||1141mm - 44.9"||1165mm - 45.8"||1189mm - 46.8"||1223mm - 48.1"|
|Head Tube Length||90mm - 3.5"||100mm - 3.9"||110mm - 4.3"||120mm - 4.7"|
|Chainstay Length||433mm - 17.0"||433mm - 17.0"||433mm - 17.0"||433mm - 17.0"|
|Standover Height||727mm - 28.6"||731mm - 28.8"||734mm - 28.9"||748mm - 29.4"|
|Reach||405mm - 16.0"||425mm - 16.7"||445mm - 17.5"||475mm - 18.7"|
|Stack||586mm - 23.1"||595mm - 23.4"||605mm - 23.8"||614mm - 24.2"|
* Effective top tube
** Seat Tube length measured from center of BB to top of seat tube
All upgrade prices are relative to the standard component price.
Can I mount a chainguide to my bike?
Yes, this bike is equipped with ISCG-05 tabs for easy chainguide mounting. Most chainguides on the market that are made for this standard should work.
Is the 148x12 derailleur hanger the same as the 142x12 hanger?
No, it's not. We had to make a new derailleur hanger to go with the new dropout. They look similar, but the easiest way to tell them apart is the finish. Our 142x12mm hangers have a bead-blasted finish, while the 148x12mm hangers have a smooth, machined finish.
Should I grease the headset cups when I install them?
Yes, we recommend this. Do not use the Carbon Assembly Compound on the headset, as it will make it more difficult to remove from the frame.
What is the torque spec for the seat collar?
We don't provide a torque spec for the seatpost, because it really depends on what seatpost you are using. Some seatposts are slippery, and require more torque to stay put, and others are very thin- and can be crushed by overzealous tightening. Some are both slippery and thin... Make sure you use the Carbon Assembly Compound included with your frame, and use some common sense.
You will not damage your frame by overtightening the seat collar, assuming you have a 31.6 seatpost in there.
What Kind of Front Derailleur do I Need?
The updated versions of the Bronson, 5010, and Tallboy use Shimano side-swing front derailleurs. The names and part numbers are:
Shimano XT M8020 Side Swing
Shimano XTR M9020D Side Swing
What kind of headset does this bike use?
We use a headset generally referred to as "mixed tapered". This is a 44mm internal upper cup, with an external 49mm lower cup. The SHIS name is ZS44/28.6 EC49/40.
What kind of rear brake adaptor do I need?
This frame uses a standard IS rear brake mount. Just pick your rotor size and order the correct adaptor to go from IS to post mount (all modern brakes).
What size bottom bracket shell does this bike use?
We use a standard 73mm threaded BB. Nearly any crank on the market (besides BB30 cranks) will fit.
What size seatpost do I need?
This bike uses a 31.6mm seatpost. Always ensure it is inserted into the frame a minimum of 4" (100mm).
|Front Derailleur||Direct to Frame|
|Headset/Headtube||mixed taper 1.5" Lower, 1'1/8" upper|
|Eye to Eye length||200mm|
|Max Tire Size||2.4"|
|Water Bottle Mounts||2x bottle cage mounts|