2025 DIY Carbon Bikes JK27 Base S
Build
650B/27.5 in × 2.1 in
Insights
Somewhat aggressive stack and reach vs trend of hardtail cross-country mtb bikes
Stack and Reach vs. Category Trend
View all sizes
Geometry
| Stack | 574mm |
| Reach | 396mm |
| Stack to Reach Ratio | 1.45:1 |
| Seat Tube Length, C-T | 381mm |
| Top Tube Length, Effective/Horizontal Unknown | 555mm |
| Top Tube Slope | 25deg |
| Head Tube Angle | 69.5deg |
| Seat Tube Angle | 74.5deg |
| Head Tube Length | 90mm |
| Bottom Bracket Drop | 45mm |
| Bottom Bracket Height | 300.3mm |
| Chainstay Length | 425mm |
| Chainstay Length Horizontal | 422.6mm |
| Front-Center | 628mm |
| Front-Center Horizontal | 626.4mm |
| Wheelbase | 1049mm |
| Fork Offset/Rake | 45mm |
| Trail | 81.1mm very high |
| Mechanical Trail | 75.9mm |
| Wheel Flop | 26.6mm |
| Tire to Pedal Spindle Distance With 170 mm cranks | 112.7mm |
| Pedal Spindle to Ground Clearance With 170 mm cranks | 130.3mm |
Base Build
| Wheel Size | 650B, 27.5 inch (584mm BSD) |
| Tire Width | 2.1in |
| Tire Outer Diameter | 690.7mm |
| Bike Length with Tires | 1739.7mm |
| Suspension Type | Hardtail (Front suspension) |
| Bar Type | Flat Bar |
| Fork Travel | 110mm |
| Suspension Sag | 20% |
| Frame Material | Carbon/Composite |
| Fork Material | Unknown |
| Brake Type | Disc |
Published Sizing Recommendations
| Height | 5 ft 3 in to 5 ft 6 in |
Source:https://www.diycarbonbikes.com/collections/junior-kids-frames/products/dcb-jk27-junior-kids-trailcraft-timber-27-5-style-mountain-bike-frame