Sometimes you’re hooked on the bike park...

...sometimes you want to push the limits of your endurance on big mountain rides, the bottom line is that your bike requirements and preferences will change over time. Traditionally, you’d reach for a different bike for each of these riding styles. But what if there were a better way? What if, instead of buying a whole new bike, you could swap a few components to change your suspension travel, wheel size, and geometry? This idea is the foundation of the Modular Frame Platform.

The Guerrilla Gravity Modular Frame Platform brings new meaning to the quiver-killer bike. With this new platform, riders are able to convert their bike to another model simply by swapping out the Seatstay Tuning Kit and a few components around. Seatstay Tuning Kits are used to define each particular model and are paired with the properly sized shock for the correct setup. Depending on the models you are swapping in between, you may also want to swap forks, wheels, or the lower cup of the GeoAdjust Headset cup (more info that below).

Where did the idea come from?

The design inspiration behind the Modular Frame Platform comes from our engineers’ background in race car design. Race teams typically have one primary vehicle equipped with a toolbox full of tuning options that allows them to optimize the the ride height, frame geometry, and leverage ratios in order to set the fastest lap times on any given track. This type of adjustment initially inspired our binary Plush / Crush and Trail / Gravity modes, but now we've taken the level of tune-ability to the next level thanks to the new Modular Frame Platform.

Guerrilla Gravity Seatstay
Guerrilla Gravity GeoAdjust Headset

GeoAdjust Headset

The first key feature to the Modular Frame Platform is a unified front triangle with its GeoAdjust Headset. With the GeoAdjust Headset you can quickly and easily adjust the reach and wheelbase of your frame by 10 mm. This allows you to dial in your frame’s fit based on your unique dimensions, as well optimizing the handling for your local terrain. For example, riders may use the shorter setting for the average trail ride, while using the long setting as a “turbo button” when heading to the bike park.

Just like any normal headset, the GeoAdjust Headset consists of upper and lower cups. While the upper cup is used across the entire line, there are two lower cup options for the GeoAdjust Headset, a 0 mm cup and taller 15 mm cup.

The 0 mm cup is designed to work best with 29” forks and the 15 mm cup with 27.5” forks. Feel free to use either cup to fine tune your stack height, head tube angle, and bottom bracket height. The possibilities for bike nerdery are next-level. This is why both cups are available when you purchase your Seatstay Tuning Kits, as well as individually in our online store.

GeoAdjust headset: Quickly adjust reach and wheelbase by 10 mm by using a headset cup flipchip system. Drop the fork, flip the chips around, and you're done.

Guerrilla Gravity GeoAdjust Headset

Seatstay Tuning Kits

One platform, four models.The second key feature are the Seatstay Tuning Kits, allowing the unified front triangle to be paired with unique, model-specific seatstay kits to “tune” your bike for varying ride styles and terrain. Swapping seatstays and requisite components is designed to take a competent home mechanic less than an hour, so you can quickly prepare for a day in the bike park or weekend bikepacking trip.

Perhaps your hometown trails don’t require a long-travel bike but you’ll take regular trips to big mountain terrain or bike parks a few times a year? So you have a Trail Pistol as your daily ride and have The Smash kit on hand for a confidence boost in the steeps. Or you love whippin’ 27.5 wheels in the park but prefer 29er wheels for all-around trail riding so you ride The Smash and swap over to a Megatrail kit when you make your pilgrimage to the park. With minor tweaks to the frame and components, this platform can take you anywhere.

Seatstay tuning kits: Easily move from one bike model to another to optimize for speed or fun (but if you ask us, fast is fun). Seatstay Tuning Kits allow you to change frame geometry, wheel size, and travel, giving you total flexibility to experiment.

Guerrilla Gravity GeoAdjust Headset

Installation & Tech Info

Installing the Seatstay Tuning Kits requires only 5 and 6 mm hex wrenches, but be sure to bring your three-way out just in case you’re removing the stem and fork. It’s as simple as removing the shock, rear axle, and the two pairs of bolts connecting the seatstays to the swing arm and rocker link. Reverse these steps and you’re ready to rock!

Iffy on your home mechanic skills, or just prefer to have your local shop handle your maintenance? The Seatstay Tuning Kits are available through our Shop Direct sales channel, allowing your favorite local shop to order up everything you need.

What's Included?

The Seatstay Tuning Kit includes all hardware necessary to install on your GG Modular Frame.

  • Seatstays
  • Bearings
  • Derailleur hanger and bolt
Not included:

Generally, what's not included are the parts you need to remove anyways in order to swap components (e.g. axle and frame hardware) or that aren't removed in the first place (e.g. rocker). Also, any necessary components will need to be purchased with the kit (e.g. shock, fork).

If switching between wheel sizes, we recommend getting an additional lower cup for your GeoAdjust Headset. The 0 mm cup is designed to be used with 29" forks; the 15 mm cup is designed to be used with 27.5" and 27.5" Plus forks.

Frames with the Modular Frame Platform:

The Smash
Trail Pistol
Shred Dogg