Living Up To The Hype

The Bronson is the reference for all-mountain riding and racing, and one of our most versatile and popular models ever. 

With a 67° head angle, 150mm of VPP™ travel and 27.5" wheels, the Bronson screamed onto the Enduro World Series scene like a Group B rally car.

The winning formula is Bronson's ability to deliver massive uphill capability too, thanks to a balanced geometry and efficient pedaling platform that speeds you between liason stages.

Now availble at an unprecendented carbon entry price point for R and S builds, the Bronson sets the all-mountain standard once again.

Looking for a heavier hitter?  Then take a look at the Nomad.

Prefer something a touch lighter and more agile?  The 5010 could be right up your street.

Or how about Bronson geometry in lower cost package?  The single-pivot Heckler shares a Bronson-esque geometry and hits everything just as hard.

Proud owner of a new Bronson? Take a minute to register it with us. 

 

Key Features:

  • Wheel size: 27.5"
  • Rear travel: 150mm

Geometry & Sizing

Rollover table below to highlight frame dimensions.

All measurements reflect installation of a fork with a 544.4mm axle-to-crown height.

SMLXL
Reach375mm14.76"403mm15.87"428mm16.85"448mm17.64"
Stack584mm22.99"594mm23.39"594mm23.39"612mm24.09"
Head Tube Angle67°67°67°67°67°67°67°67°
Seat Tube Length407mm16.02"432mm17.01"470mm18.5"508mm20"
Front Center
BB Height346mm13.62"346mm13.62"346mm13.62"346mm13.62"
BB Drop
Wheelbase1108mm43.62"1139mm44.84"1165mm45.87"1192mm46.93"
Chainstay Length439mm17.28"439mm17.28"439mm17.28"439mm17.28"
Head Tube Length90mm3.54"100mm3.94"100mm3.94"120mm4.72"
Top Tube Length554mm21.81"584mm22.99"610mm24.02"635mm25"
Seat Tube Angle73°73°73°73°73°73°73°73°
Standover Height718mm28.27"731mm28.78"733mm28.86"749mm29.49"
Eye to Eye Length

27.5" Frame Sizing

s
5'0"152 — 5'5"165cm
m
5'5"165 — 5'10"178cm
l
5'10"178 — 6'1"185cm
xl
6'1"185 — 6'6"198cm

Tech Support

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.

Can I use a dropper post on this bike?

Yes- we've provided routing for both internal (stealth) and external remote cables.

It looks like the lower link is off center in my frame- is everything ok?

Yes- this is correct. With our newer pivot system, the pivot axle draws the link over to one side in order to properly preload the bearings. This offset is accounted for in the frame design so everything ends up nice and straight in the end.

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 fork sizes are recommended?

We recommend 150-160mm travel. All of the forks we spec are 150mm, which we feel balances the bike the best.

What is the torque spec for the front derailleur?

Torque the front derailleur to 45 in/lbs.

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 carbon frame, and use some common sense.

You will not damage your frame by overtightening the seat collar, assuming you have a 30.9mm seatpost in it.

What kind of front derailleur do I need?

This bike uses a 34.9mm Bottom Swing (high clamp), Top Pull front derailleur.

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 q-factor should I use for the cranks?

On any crank with optional Q-factor, choose the wider version.  166 for Sram XX, or 168 for XX1.  For Shimano doubles, we recommend the M980.  

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 rear hub do I need?

This bike uses a 142x12 through-axle rear hub, and includes a DT RWS axle.

What size seat collar do I need?

Bikes with a 30.9mm seatpost require a 34.9mm seat collar. 

What size seatpost do I need?

We use a 30.9mm seatpost. Always ensure it is inserted into the frame a minimum of 100mm (4").

What size shock does it use?

This bike uses a 200x57mm shock with 22x8mm eyelet hardware (21.8mm x 8mm for SRAM). Please do not use any other shock size or modify with eccentric shock bushings- this can cause damage or clearance issues with the frame.

What's the largest rotor I can run on the Bronson?

The Bronson will accept up to a 203mm rotor with the correct IS adapter. 

Why does this frame use a standard thread-in bottom bracket, when many of your competitors use press-in style (BB30, Pressfit 30, BB90, BB92, BB86)

It is true that there are some slight weight savings available with the various pressfit bb designs (exact weight savings obviously vary depending on system, frame manufacturing techniques, and crank model), but we don't feel this small savings make up for the inconveniences. We are still able to make a frame that is lighter than most of our competitors, while still using a heavier bb system. There are a number of disadvantages that exist with press fit systems:

1) Special installation and removal tools are required for these parts, including a headset press. This is not convenient for most home mechanics, and they are quite expensive. Traditional external BB's can be installed or removed with a simple $10 hand tool.

2) "Permanently installed cups". Shimano doesn't recommend removing and re-installing their press in bb cups (as they may become damaged), so moving parts from bike to bike is no longer an option. http://techdocs.shimano.com/media/techdocs/content/cycle/SI/SI_0053A_001...

3) Creaking or shifting bb's can be common with these systems. Since the bearing is pressed into a cup, which is then pressed into the frame- it can be hard to get all of the press fits snug- without being too tight on the bearing or too loose in the frame.

4) Reasonable tube sizes. One of the most commonly claimed advantages of a larger bb shell is the larger diameter downtube that goes with it. This may be an advantage on road bikes, where tubes can be incredibly thin and large for optimal stiffness. On a mountain bike, this area of the frame sees a lot of abuse from rocks and crashing, and needs to have a certain amount of wall thickness to survive actual use. Using what we consider a "safe" wall thickness and carbon layup, and a fairly typical tube diameter, we get an exceedingly stiff, light, durable product. If we used a larger downtube, we would either have a heavier frame (same wall thickness but larger diameter), or a less durable product (thinner walls and larger diameter).

5) Chain clearance. Take a look at some of our competitors frames with press in bb shells. The down tube comes so close to the chainrings that many frames have chainsuck guards on the downtube! In our mind, the chain should be able to fall off on a mountain bike and not get jammed between your crank and thin-walled carbon downtube.

6) Backwards compatibility: Many of our customers purchase a frame and build it up with their choice of parts, or parts from an old bike. By using a standard bb, we are compatible with everything without requiring confusing adaptors.

7) Chainguide compatibility: While it may seem strange to talk about putting chainguides on a short travel bike, it is becoming more common now with 10 speed drivetrains. Thread in bb's mean the frame is compatible with bb mount chainguides. We like versatility....