Nukeproof Mega Carbon Geometry: Compare the 297 and 290 Medium
Nukeproof Mega Carbon geometry should retain the platform label beside the size. In the 2023 MK4 manual, the medium 297 and medium 290 charts both list 455 mm reach and 621.16 mm stack. Their chainstay and wheelbase rows differ, however. One matching pair of numbers therefore does not make the frames or complete bicycles identical, and a familiar Medium label is not a personal fitting guarantee.
Nukeproof Mega Carbon geometry: Compare the same size across the named tables
Printed page 38 gives the medium 297 a 435 mm chainstay and 1217.48 mm wheelbase. Page 39 gives the medium 290 a 440 mm chainstay and 1222.48 mm wheelbase. Each difference is 5 mm by subtraction of the published values. That is an arithmetic comparison of the manual’s entries, not a measured handling result or proof of how either bicycle will suit a particular trail.
Both Medium columns list a 410 mm seat tube, 77.5-degree effective seat-tube angle and 71-degree actual seat-tube angle. Keep effective and actual angles labelled: they are separate rows in the document. Likewise, the saddle-height and offset rows should not be turned into a prescription for every rider merely because they appear beside the frame geometry.
Notice the reference setup and inconsistent source entries
Both charts give 170 mm fork travel and a 42 mm offset. Their axle-to-crown references differ: 584 mm in the 297 table and 582 mm in the 290 table. These are documented reference entries, not permission to transfer an unknown fork between platforms. The earlier 290 specification table also gives 44 mm offset, so that disagreement must remain visible in a fork-related enquiry.
The page 36 specification’s 290 size listing is M/L/XL, while page 39 displays five geometry columns. Do not treat the wider chart as evidence that every size is currently offered. Another printed anomaly is the 290 Small top-tube figure of 647.71 mm. This comparison deliberately uses the identified Medium columns rather than silently rewriting an unusual neighbouring value or using it to judge fit.
Bring the actual complete bicycle into the comparison
A used example may carry a different stem, handlebar, saddle or suspension configuration from its original build. Those details affect the fitting discussion and cannot be established from a chart alone. Identify the actual frame and installed parts, then compare contact points consistently with a suitable retailer or fitter rather than expecting one frame dimension to determine the final position.
The Nukeproof topic provides surrounding coverage and the family guide distinguishes the models. The practical comparison is between confirmed platforms and real assembled bicycles. Use the shared reach and stack as a starting observation, keep the documented differences and unresolved source entries attached, and assess the rider’s fit separately from the catalogue’s size name.
FAQ
Are the medium 297 and 290 reach and stack entries equal?
Yes. Both tables give 455 mm reach and 621.16 mm stack.
How much longer is the listed medium 290 wheelbase?
It is 5 mm longer by subtraction: 1222.48 mm rather than 1217.48 mm.
Can matching geometry entries prove the correct size for a rider?
No. Frame identity, actual setup and an appropriate fitting assessment remain necessary.
Sources
The MK4 medium 297 and 290 tables share reach and stack but differ in chainstay and wheelbase entries. Read the platform labels and source limitations before comparing fit. Printed pages 36, 38, 39 of the 2023 Mega MK4 Carbon manual (https://cdn.shopify.com/s/files/1/0438/3296/7322/files/MY23_-_NP_-_Editorial_-_Mega_Carbon_Bike_Manual.pdf?v=1687182192), retrieved 28 October 2026, support this model-specific explanation.
Photograph credits and permissions
Photograph 1
Original title: Figure 25(b), complete bike assembly, in Analysis of Symmetrical/Asymmetrical Loading Influence of the Full-Suspension Downhill Bicycle’s Frame on the Crack Failure Formation at a Critical Point during Different Driving Scenarios and Design Improvement
Creator: Vladimír Bulej, Ivan Kuric, Milan Sága, Milan Vaško, Zuzana Ságová, Michal Bartoš and Stanislaw Legutko; individual photographer not specified
Copyright notice: © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
Original source URI: https://mdpi-res.com/d_attachment/symmetry/symmetry-14-00255/article_deploy/symmetry-14-00255.pdf
License / permission: CC BY 4.0 International
License / permission URI: https://creativecommons.org/licenses/by/4.0/
Modification notice: Selected photo panel(b): JPEG object687 extracted without re-encoding from the source PDF. The separately downloaded source PNG contains panels(a)+(b); it is not the delivered JPEG. No visual edits applied.