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56

cap and rotor

Worth a look

Shows a sweet-spot price point ($23.90 avg), but a failed launch gate (market size, growth, or returns) keeps it on the watch list.

Market size 13Growth 23Conversion 52Competition 92Returns 42Price range 85Avg price 95Brand share 82Review moat 86Quality gap 60

Avg price

Incredible$23.90

avg listing price — sweet spot $15–$100

Competition

Great23%

top-5 click share — an open shelf

Review moat

Great283.65

avg incumbent reviews — the moat a new listing must climb

Price range

Great$7.64–$69.46

cheapest to priciest tracked listing — scored on the share inside $15–$100

Brand share

Great53%

top-5 brand share — no brand owns this niche

Quality gap

Good4.4★

avg incumbent rating — lower means beatable quality

Conversion

Good4.3%

search→purchase rate — share of searches ending in a sale

Returns

Okay3.9%

return rate — above 6% kills the launch gate

Growth

Bad-3.6%

90-day search growth — must beat 0% to launch

Market size

Bad$51K

$51K/yr · 50K searches

Competition

Clicks spread well past the top 5 (23% combined) — an open shelf where new products get seen.

Brands

29 rising

Sellers

134

Top-5 brand share

53%

Open market

42%

  • AIP Electronics18%
  • GM GENUINE PARTS13%
  • ACDelco11%
  • Standard Motor Products6%
  • MSD6%
  • big-autoparts5%

Product shelf

Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.

0%2%$1K4%$2K6%$3K8%$4K1101001K10K Reviews — right = deep review moat Market share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)3 products missing review or click data not plotted

All 72 tracked products in this niche — three views at once, no toggling.

Demand & seasonality

Weekly Amazon search volume, last 59 weeks — -3.6% search growth over the last 90 days.
1K800Spike '26JunJulAugSepOctNovDecJanFebMarAprMayJun

No pronounced peak months · busiest ÷ quietest = 1.4×

Reviews

What buyers praise and complain about, mined from review topics.

What buyers love

Size-Overall27%

“Excellent fit”

Quality-Overall23%

“Very good product, works well, lasts a long time”

Value For Money13%

“Good price”

Efficiency11%

“The engine ran perfect”

Advertised Vs Actual Product8%

“Just as described”

Assembly/Installation4%

“Installed and works as expected”

Functionality-Overall2%

“very close works great”

Color2%

“Color”

Motor Power1%

“My engine runs much better than with the worn out old pieces”

Strength1%

“Really sturdy”

What buyers complain about

Quality-Overall19%

“Bad quality”

Size-Overall14%

“Rotor did not fit”

Durability14%

“Made be break down 5 k miles later”

Defective Material/Parts7%

“Broke as soon as I was tighten screw”

Advertised Vs Actual Product6%

“Deceptive”

Color5%

“Did not come in blue”

Rusts/Corrodes5%

“allowing aluminum to corrode”

Value For Money3%

“Not the cheapest”

Socket/Port/Plug3%

“The plug for the cap wouldn't fit”

Compatibility-Overall3%

“Did not fit”

Top return reasons

Size-Overall36%
Defective Material/Parts14%
Compatibility-Overall13%
Color8%
Advertised Vs Actual Product6%
Functionality-Overall4%
Product Condition3%
Value For Money2%
Assembly/Installation2%
Quality-Overall2%