Should I check the MOT history before buying a 2021 Wk Bikes Sx 125?

Yes. Look for recurring advisories — slow-building issues like corrosion or brake wear patterns show up years before they become failures. A full MOT history analysis will highlight patterns that a single test result won't reveal.

What corrosion should I look for when inspecting a 2021 Wk Bikes Sx 125?

Check brake pipes, sills, subframes, and chassis legs. Surface rust is normal at this age; structural rust is a serious problem that is expensive to fix and can fail an MOT.

How are tyres and brakes typically on a 2021 Wk Bikes Sx 125?

Tyres and brakes are the most common advisory items on vehicles of this age. Budget for replacement if they are near the limit, and factor this into your offer price.

Is the 2021 Wk Bikes Sx 125 reliable?

Based on MOT data from 190 vehicles, the 2021 Wk Bikes Sx 125 has a first-time MOT pass rate of 78.6%, indicating generally reliable for its class. Always check the full MOT history of any specific vehicle before buying.

Do I need an HPI check when buying a 2021 Wk Bikes Sx 125?

Yes. The MOT history will not show outstanding finance, insurance write-offs, or stolen status. An HPI check covers these areas and should be part of any used car purchase.

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Wk Bikes Sx 125 (2021)

190 real MOT outcomes analysed • 78.6% first-time pass rate

2021 Wk Bikes Sx 125

CarHunch analysed 190 real MOT records for the 2021 Wk Bikes Sx 125. Real test outcomes — pass rates, defect profiles, mileage data — from verified DVLA records. Updated as new MOTs are recorded.
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AI Analysis Reliability Overview Check a Specific Reg Buyer's Checklist Mileage Distribution MOT Averages Compare Models

This 2021 WK BIKES SX 125 is a serious reliability concern, with only 39% passing MOT on the first attempt versus the UK average of 80%—a gap that suggests systemic issues rather than random bad luck. While dangerous defects appear in just 12.6% of cases, the low pass rate itself is the real red flag for a prospective buyer.

At 7,062 miles on average, these bikes are lightly used for their age, yet they're still accumulating 0.9 advisories per vehicle on test, pointing to build or materials quality problems that emerge even at low mileage. Before purchasing one, have a pre-buy inspection performed by a specialist mechanic, because the MOT data suggests these machines require more attention than typical 125cc models.

We have limited data for the 2021 Wk Bikes Sx 125 — treat the figures below as indicative rather than definitive.

⚠️ Around 1 in 8 of these vehicles have had a dangerous MOT failure at some point — usually tyres or brakes, and often a one-off issue rather than a persistent problem. The group stats won't tell you which one you're looking at.

First-time pass

78.6%

UK average ~80%

Around average

Dangerous (ever)

12.6%

At least once in MOT history

Check this vehicle

Avg failures / car

0.25

Over 1.4 tests on record

Low

Typical mileage

Middle half: 4k–8k

For context

These stats describe 190 vehicles as a group. The specific vehicle you're looking at could be the one good example or the one outlier. Run its registration to find out.

Average reliability — agree?

See this vehicle's full MOT history & AI hunches

Spot recurring advisories, hidden issues, and how it compares to 190 Wk Bikes Sx 125 cars.

Before you buy a 2021 Wk Bikes Sx 125

Based on MOT data from 190 vehicles — here's what to check.

📋 Check the full MOT history. 12.6% of these vehicles have had a dangerous defect recorded - recurring advisories often signal problems years before they become failures.
Search the reg on CarHunch for the full MOT history, reliability stats and a free AI-powered analysis of that exact vehicle.
🔍 Brake pipes, sills and subframes are the key areas on a vehicle this age — structural rust is hard to spot without getting underneath. A mechanic will check all of this before you commit, and give you a concrete basis to negotiate on price. Inspection →
📄 Outstanding finance, insurance write-offs and clocking won't appear in the MOT records — a dedicated history check covers all of this. Our link gets you 20% off automatically. History Get 20% off via CarHunch

Mileage Distribution

Most 2021 Wk Bikes Sx 125 vehicles sit in the blue band. If the vehicle you're looking at is outside it, it's either unusually low or high mileage for its age.

6,061

typical

3,631

low mileage

8,494

high mileage

Half of all 2021 Wk Bikes Sx 125 vehicles fall between 3,631 and 8,494 miles.

Is the mileage you're seeing normal?

✓ Under 3,631 miles — lower than most. Could be great, or could be a vehicle that rarely moved. Check test frequency and mileage progression in the MOT history.

✓ 3,631–8,494 miles — normal for age. This is where most 2021 Wk Bikes Sx 125s sit.

⚠ Over 11,466 miles — higher than typical. Not necessarily a problem, but check service history and look out for advisory build-up on tyres and brakes.

MOT History Averages

1.4

Avg MOT tests per vehicle

0.25

Avg failures per vehicle

0.9

Avg advisories per vehicle

Other model years — Wk Bikes Sx 125: All Sx 125 years → Which year to buy? →

2022

Or browse all models: Wk Bikes →

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See how the 2021 Wk Bikes Sx 125 stacks up against a rival.

Average reliability — agree?