2025 Topstone Carbon 3 GRX - 1x Gravel Road Bike
Every bike is fully assembled, tuned, and test-ridden before pickup at your chosen DFW Bike Mart location.
Expected to ship within 14 days.
Professionally built and test-ridden before it ships. Arrives mostly assembled with just minimal setup needed. See Reassembly Instructions
Delivered fully assembled and tuned by Bike Mart - ready to ride right at your doorstep within 10 miles of any DFW location.
Complete your Ride
What is the Bike Mart Return policy?
What is the Bike Mart Return policy?
Bike Mart offers a 14-day return and 30-day exchange policy in effect on qualifying items. Restocking fee may apply for "At Warehouse" Items. Read More
What Financing options does Bike Mart offer?
What Financing options does Bike Mart offer?
Financing is easier than ever at Bike Mart. With Synchrony Financial, you can choose:
- 0% APR for 6 months — on orders under $999
- 0% APR for 12 months — on orders of $1,000 or more
We also support HSA/FSA Funds with TrueMed, Shop Pay Installments and PayPal Financing.
Ship
Get your bike or equipment delivered to your home directly from Bike Mart via our FedEx or USPS Carrier partners. Adult signature is required for all bike deliveries and for equipment & gear deliveries over $500.
For orders that include a bike, it will be professionally pre-built and shipped to your home with minimal assembly needed. While we try to make it as easy as possible, basic mechanical skills and proper tools are required.
If you decide to take your bike to a local bike shop for assembly, additional fees will apply.
Pickup
We’ve made it easier than ever to get the gear and bikes you love—fast. With our Buy Online, Pick Up In Store (BOPIS) option, you can shop online and pick up your items at your convenience from any of our six DFW locations.
The best part about picking up at a Bike Mart location is that you get the same high quality service with the convenience of having the exact bike or part.
Bikes / Car Racks will be assembled and installed at no extra charge and might require additional processing time for assembly.
Delivery
When you select "Home Delivery" at checkout. Your bike will be professionally assembled and the closest Bike Mart store will call you to schedule the delivery.
We offer home delivery for bike purchases only within 10 miles of a Bike Mart location. Contact us if you live beyond 10 miles and we can discuss more options. Additional fees may apply.
In stock bikes will be delivered within 7 days. Warehouse bikes will delivered within 14 days*.
2025 Topstone Carbon 3 GRX - 1x Gravel Road Bike
Features
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KingPin
Our innovative gravel rear suspension is light, simple, and effective. A thru-axle pivot in the seat tube allows the rear triangle and seatpost of the bike to flex vertically, delivering up to 30mm of bump-smoothing travel.
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StashPort + StashBag
StashPort is our take on a downtube storage system, accessed beneath the water bottle cage. Every bike includes StashBag, a specially designed bag for your essentials.
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Tire Clearance
Lots of room for modern gravel rubber. The frame clears tires up to 52mm wide with a single ring setup, or 45mm for a 2x, while the fork fits up to a whopping 56mm wide tire. Measured size, of course.
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Dropper Ready
Built to accept an internally-routed 27.2mm dropper seatpost, which shouldn´t be a surprise on a bike this capable.
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Proportional Response
Tuned for the rider, our size-specific construction creates optimal stiffness and compliance for each frame size. So, every rider benefits from the ideal ride feel and comfort of KingPin.
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OutFront Steering Geometry
Confident stability meets nimble agility. An extra long fork offset paired with a slack head angle keeps the steering light and lively, yet delivers unreal confidence at speed and in the rough stuff.
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Tidy does it
Internal cable routing throughout the frame, combined with Conceal Stem, delivers a tidy, integrated look.
Always Game
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Smiles for Miles
Kingpin is our lightweight, go-for-longer rear suspension. Maintenance-free and complexity-free, it gives the Topstone frame legit rear-wheel travel without compromising stiffness for the sprint. Kingpin provides a smoother ride, more traction to push harder, and more give to take on the rough stuff. You’ll hardly know it’s there, but you’ll be very glad you’ve got it.
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Bring It All
Our all-new StashPort storage system in the downtube is designed to be concealed yet convenient. Paired with the special StashBag, you can bring your essentials along for the ride and know that they’ll be kept safe, whatever you get up to out there. Meanwhile, multiple mounting points on the frame, mean more gear and more adventures.
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Tuned Ride
A dialed-in ride, just for you. AKA: Proportional Response Construction. Everything from the carbon layup to the geometry on Topstone is individually tuned by frame size. So that the bike – including KingPin suspension – works in harmony to give you the best ride for you and your dimensions.
Overview
Overview
Always Game
Our take on the ultimate all-round gravel bike. Go anywhere, bring everything and then keep on going.
Model Description
One chainring, endless possibilities. The Topstone 3 GRX - 1X delivers simplicity without sacrificing performance. A Shimano GRX610/820 blended group keeps shifting precise and reliable, while KingPin suspension takes the sting out of rough terrain. WTB tires keep you connected to the trail, making every ride a good one—whether it’s a quick lap or a full-day escapade.
What it's for
Gravel riding & racing, bikepacking, going hard and long on dirt or pavement
Highlights
- Lightweight full carbon frameset with Kingpin rear suspension, Proportional Response size-specific construction and StashPort downtube storage
- With a single chainring and wide-range SLX 12-speed cassette, this blend of Shimano’s top-end GRX820 and GRX610 gravel groups offers a killer performance value
- Durable, dependable WTB ST i25 rims, with Shimano hubs and WTB Riddler 45c gravel tires
- Cannondale 3 flared handlebars offer comfortable, gravel-friendly hand positions
Technical Specifications
Technical Specifications
| Platform | Topstone Carbon |
| Model name | Topstone Carbon 3 GRX - 1x |
| Model code | C15195U |
| Frame | Topstone Carbon, Kingpin suspension system, Proportional Response construction, downtube Stashport, internal cable routing, 12x142mm thru-axle, 27.2 dropper post ready, UDH, BSA 68mm threaded BB, flat mount disc, removable fender bridge, multiple gear/bottle mounts |
| Fork | Topstone Carbon, 1-1/8" to 1.5" steerer, 55mm OutFront offset, flat mount disc, internal routing, 12x100 thru-axle, triple bottle/gear mounts, fender mounts |
| Headset | Acros IS52/40 ICR |
| Rear derailleur | Shimano GRX 822, Shadow SGS |
| Shifters | Shimano GRX 610, 12-speed |
| Chain | Shimano M7100, 12-speed |
| Crank | Shimano GRX 610, 40T: 165mm (47cm), 170mm (51cm), 172.5 (54-56cm), 175mm (58-61cm) |
| Rear cogs | Shimano SLX M7100, 10-51, 12-speed |
| Bottom bracket | Shimano BSA 68 |
| Brakes | Shimano GRX 610 hydraulic disc, 160/160mm RT70 rotors |
| Brake levers | Shimano GRX 610 hydraulic disc |
| Rims | WTB ST i25 TCS, 28h, tubeless ready |
| Spokes | Stainless Steel, 14g |
| Tire size | 45 |
| Wheel size | 700c |
| Hubs | (F) Shimano TC500, 12x100mm centerlock / (R) Shimano TC500, 12x142mm centerlock |
| Tires | WTB Riddler TCS Light, 700x45c, tubeless ready |
| Handlebar | Cannondale 3, butted 6061 Alloy, 16 deg flare, 120mm drop: 400mm (47cm), 420mm (51-54), 440mm (56-61cm) |
| Stem | Cannondale C1 Conceal, Alloy, 31.8, -6°: 70mm (47-51m), 80mm (54cm), 90mm (56-58cm), 100mm (61cm) |
| Grips | Cannondale KnurlCork, 2.7mm |
| Saddle | Selle Royal SRX Open |
| Seatpost | Cannondale 3, 6061 Alloy, 27.2x350mm |
| Extra 1 | Large StashBag downtube storage bag, tubeless valve stems |
| Ingestion hazard | WARNING - INGESTION HAZARD: This product contains a button cell or coin battery. DEATH or serious injury can occur if ingested. A swallowed button cell or coin battery can cause Internal Chemical Burns in as little as 2 hours. KEEP new and used batteries OUT OF REACH OF CHILDREN. Seek immediate medical attention if a battery is suspected to be swallowed or inserted inside any part of the body. |
Parts are subject to change without notice. Chat with us if you have any questions.
Geometry
Geometry
Length measurements converted to mm from Cannondale inch values. Angles in degrees.
This Geometry Chart is provided by the Manufactuer. Chat with us if you have any questions.
Sizing
Sizing
| size | inches | cm |
|---|---|---|
| 47 | 4'11" - 5'6" | 150 - 168 |
| 51 | 5'5" - 5'9" | 165 - 175 |
| 54 | 5'8" - 5'11" | 173 - 180 |
| 56 | 5'10" - 6'1" | 178 - 185 |
| 58 | 6'0" - 6'4" | 183 - 193 |
| 61 | 6'3" - 6'7" | 191 - 201 |
Sizing to be used as a reference only. Chat with us if you have any questions.
Why Shop at Bike Mart?
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Live Chat with Real People
Get instant advice and answers from our team of cycling experts through our online chat feature or over the phone.
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Community-Focused
We have donated over a million dollars to support our communities through charity rides, bike rallies and advocacy for more bikeable trails in Texas.
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Professional, Quality Assembly
Our bikes are expertly assembled and inspected by Bike Mart’s professionally trained staff. They ensure proper adjustments, tighten and true wheels, and get your bike ready to ride.
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Our Legacy of Excellence
With 62 years of retail experience, Bike Mart brings unparalleled expertise and dedication to serving you.
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10% off accessories with new bike purchase
Receive 10% off all accessories purchased with a new bike.
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Hassle-Free Returns
Easily initiate returns for online orders with our straightforward return policy to shop with confidence.
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Locally Owned & Operated
A family of cyclists who live and ride in your community—feel right at home.
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Free accessory installation with new bike purchase
Let our experts install your accessories at no extra cost, ensuring everything fits perfectly and is ready for your ride!
