How we select and verify gear
Start with the part most gear sites bury: BikeSize does not lab-test or ride-test anything it recommends. We have no test rig, no crash sled, and no fleet of sample products. Any site that tells you a helmet “felt secure on long descents” without saying who rode it and where is asking you to take a sentence on faith.
What we do instead is documentary. A pick has to be traceable to something a manufacturer or a standards body published, with the link and the date recorded. That is a narrower claim than hands-on review, and it is one you can check yourself.
The evidence hierarchy
When two sources disagree, the higher row wins. A retailer listing never overrides a manufacturer size chart, and marketing copy never overrides a certification label.
| Rank | Evidence | What it can support |
|---|---|---|
| 1 | Certification records and safety standards (CPSC, EN 1078, ASTM, and the labels a manufacturer prints on the product) | Any safety claim. A helmet cannot be recommended here without a certification label recorded against the specific sizes it applies to, each with its source link. |
| 2 | Manufacturer-published specifications: product pages, size charts, support articles, and manuals | Sizes, circumference ranges, intended use, weights, materials, and fit guidance. Each record stores the publisher, the source type, the URL, and the date it was retrieved. |
| 3 | Named third-party testing published by the organisation that ran it | Comparative performance claims, always attributed to the body that did the testing. Never presented as our own work. |
| 4 | Retailer listings and customer review summaries | Price, availability, and rough sentiment only. A retailer listing is never the basis for a safety or fit claim. |
- 1
- Evidence
- Certification records and safety standards (CPSC, EN 1078, ASTM, and the labels a manufacturer prints on the product)
- What it can support
- Any safety claim. A helmet cannot be recommended here without a certification label recorded against the specific sizes it applies to, each with its source link.
- 2
- Evidence
- Manufacturer-published specifications: product pages, size charts, support articles, and manuals
- What it can support
- Sizes, circumference ranges, intended use, weights, materials, and fit guidance. Each record stores the publisher, the source type, the URL, and the date it was retrieved.
- 3
- Evidence
- Named third-party testing published by the organisation that ran it
- What it can support
- Comparative performance claims, always attributed to the body that did the testing. Never presented as our own work.
- 4
- Evidence
- Retailer listings and customer review summaries
- What it can support
- Price, availability, and rough sentiment only. A retailer listing is never the basis for a safety or fit claim.
Incomplete evidence means no recommendation
This is the part that does real work. For helmets, the fit record has to be complete before a model is eligible to be recommended: published size labels, head-circumference ranges with the age group each size is meant for, the intended riding use, the headform shape where the brand publishes one, and certification labels tied to specific sizes. Every one of those carries a source URL.
A model with gaps is marked incomplete and quarantined, with the reason written down. Quarantined models are not recommended. They do not get promoted into a pick because the price is good or the commission is better. If a brand has not published what a rider needs to size a helmet safely, the honest output is silence, not a confident guess.
How a shortlist gets built
- Start from the category: what the product has to do, and the standard it has to meet to be sold for that use.
- Collect candidates that clear the evidence bar, recording source links and retrieval dates as we go.
- Drop anything quarantined for incomplete safety or fit evidence.
- Confirm the product identifier and price against the live retailer listing, and mark whether that check was actually done.
- Write up what the sources support, including the caveats. When a page needs a caveat, the caveat goes in the page.
What affiliate links do and do not change
BikeSize earns a commission on some outbound product links, and that revenue pays for the calculators and guides. Two things follow, and both are enforced rather than promised:
- Every affiliate link is labelled. Sponsored links carry
rel="sponsored"per FTC guidance and a visible disclosure sits on the page. A build-time check fails the site if a sponsored link ships without its tracking and placement attributes, so an unlabelled affiliate link cannot quietly slip through. - Commission does not create a pick. Affiliate status does not decide which products, categories, or brands get covered. A product that fails the evidence bar stays out regardless of what it pays, and a product with no affiliate link at all can still be the recommendation.
The full commercial picture is in the affiliate disclosure, and the sourcing and review rules that sit behind all of it are in the editorial policy.
What we are not
- Not a test lab. No claim here is based on our own testing, and no page should read as though it is.
- Not a retailer. We do not hold stock, and availability changes faster than any page can.
- Not a substitute for trying a helmet on. Circumference gets you to the right size range; head shape decides which model actually sits right.
Corrections
If a specification here is wrong, a certification claim does not match the manufacturer, or a product has been recalled, report it on the public issue tracker. Reports are handled in the open. We aim to respond within five working days, and anything affecting safety gets pulled first and investigated after.
Back to all methodology pages.