thundermountainbikes.com website review

About 293 KiB of JavaScript is downloaded but never used on this page. Google estimates it would make the page about 1.5 s faster on a phone.

The page has 3,565 HTML elements. Above 1,500, rendering and every interaction get slower on phones.

8 images could be 1.2 MB smaller with modern formats (WebP or AVIF) and sizes that fit a phone screen.

Your mobile performance score is 57. Pages that score under 90 lose visitors before the first paint.

8 third-party services load with your homepage (Shopify, Klaviyo and 9gtb.com and others), adding 1.7 MB and 706 ms of main-thread time.

4 files block the first paint until they finish downloading. Deferring or inlining them could save about 600 ms.

Shopify costs a phone 434 ms of main-thread work and 1.2 MB of downloads while your page loads. Loading it after the page is usable, or only on the pages that need it, takes that off the critical path.

42 KiB could be saved by minifying JavaScript.

A phone's processor spends 3.9 s on main-thread work while loading, 1.4 s of it running JavaScript. Above 2 s, taps and scrolls feel sluggish.

About 42 KiB of CSS is downloaded but never applied on this page. Google estimates it would make the page about 300 ms faster on a phone.

Klaviyo costs a phone 177 ms of main-thread work and 318 KiB of downloads while your page loads. Loading it after the page is usable, or only on the pages that need it, takes that off the critical path.

Polyfills for old browsers add 64 KiB JavaScript that modern phones do not need. Google estimates it would make the page about 200 ms faster on a phone.

12 files are served with short cache lifetimes, so returning visitors download them again (48 KiB).

4 long tasks block the main thread while loading, the longest for 97 ms. During a long task the page ignores taps.

Web fonts hide text while they load. Setting font-display: swap shows text immediately (about 50 ms).

Critical files load one after another instead of in parallel (3 chains). Preconnecting to key origins and preloading the hero image shortens the chain.

Scripts make the browser recalculate the layout repeatedly while the page loads, which wastes processor time on phones.

Real Chrome users on phones do not pass Google's Core Web Vitals on this page (28-day field data from the Chrome UX Report (opens in a new tab)). Google uses this in ranking.

Your largest element takes 15.2 s to render on a phone. Google's threshold for “good” is 2.5 s. The largest element is the text “Get 15% Off”.

The page becomes fully interactive after 17.3 s. Good is under 3.8 s.

Visually, the page fills in at 10.3 s (Speed Index). Good is under 3.4 s.

The first text or image appears after 4.5 s on a phone. Good is under 1.8 s.

Over the last 25 four-week periods to 2026-11-07, real Chrome visitors' tap response (inp) went from 103 ms to 129 ms at the 75th percentile (Chrome UX Report (opens in a new tab) history).

Real visitors see the first content after 2.0 s (75th percentile). Good is under 1.8 s.

Real visitors wait 811 ms for your server to start answering (75th percentile). Good is under 800 ms.

8 images have no width and height attributes, so the layout jumps as each one loads.

Your homepage downloads 4.2 MB in 438 requests on a phone: scripts 1.5 MB (265), images 1.4 MB (15) and other files 843 KiB (126). Under 2 MB keeps phones on slow connections fast.

new-bike-day-save-on-used-rental-mountain-bikes-mobile.jpg is on the first screen but marked loading="lazy", so the browser waits before fetching it and the page looks finished later. Load it eagerly (and give it fetchpriority="high" if it is the main image).

1 image (479 KiB) is JPEG, PNG or GIF. The same pictures as WebP or AVIF are usually much smaller at the same quality, and every current browser shows them.

By the Sustainable Web Design model, a visit to your homepage emits about 1.19 g of CO₂e: 142.9 kg a year at 10,000 visits a month. It scales with page weight, so every byte cut lowers it.

3 text elements don't have enough contrast against the background to read easily, especially outdoors on a phone.

Some lists contain elements other than list items, which screen readers announce wrongly.

2 images have no alt text, which hurts accessibility and image search.

Contentinfo landmark should not be contained in another landmark: 1 element on the page fails this check, rated moderate by axe-core.

Document should not have more than one contentinfo landmark: 1 element on the page fails this check, rated moderate by axe-core.

Landmarks should have a unique role or role/label/title (i.e. accessible name) combination: 1 element on the page fails this check, rated moderate by axe-core.

All page content should be contained by landmarks: 1 element on the page fails this check, rated moderate by axe-core.

4 visible links have no text or label, so screen readers cannot say where they go.

Elements with visible text labels do not have matching accessible names. (2 elements).

No structured data (JSON-LD), so Google can't show rich results such as your logo, ratings or FAQs.

The homepage links to 222 pages on thundermountainbikes.com and 23 external pages.

There is no Organization (or LocalBusiness) JSON-LD, so search engines and AI assistants have no machine-readable facts about who runs the site: its name, logo, profiles and contact details.

https://thundermountainbikes.com/collections/all, https://thundermountainbikes.com/collections/components, https://thundermountainbikes.com/collections/bottom-brackets, https://thundermountainbikes.com/collections/brake-sets, https://thundermountainbikes.com/collections/cassettes and https://thundermountainbikes.com/collections/chainrings and 9 others have no meta description, so Google writes the search snippet from whatever text it finds.

https://thundermountainbikes.com/collections/all and https://thundermountainbikes.com/collections/components have no <h1> headline, so visitors and search engines get no clear main topic.

We fetched 15 pages linked from your homepage (of 115 found) and read each the way a search engine does.

8 of 25 tappable elements near the top of the page are smaller than 24 px, hard to hit with a thumb.

2 errors were logged to the browser console while the page loaded, for example “Invalid left-hand side in assignment”.

Your homepage shows a street address but no LocalBusiness JSON-LD, so Google and AI assistants have to guess your address, hours and phone from the page text.

No analytics or tag manager detected in the HTML, so you can't measure whether any of these fixes work.

The homepage shows no opening hours. If customers visit or call, show when.

No guarantee or risk reducer (money-back, free trial, no credit card) is mentioned, which is often what tips a hesitant visitor.

The homepage carries about 520 words of visible text.

Before a visitor clicks anything, the page loads Google Ads, Google Analytics, Google Tag Manager, Klaviyo and Meta Pixel and 2 mores (measured from a US location before any click). No consent tool was detected. Visitors from the EU, UK and several US states must be asked first.

Opening the homepage sets 19 cookies, 1 of them by other companies (measured from a US location before any click).

No known cookie consent tool loads with the page. Some sites build their own banner, and some only show one to visitors from the EU.

Loading the homepage contacts 41 hosts run by other companies (fonts, scripts, analytics, ads), each of which sees the visitor's IP address.