---
title: "Shim Kit — $103K/yr Amazon US Niche (2026) - Flapen"
canonical_url: "https://flapen.com/research/us/automotive/shim-kit"
last_updated: "2026-08-09T13:40:42.865Z"
locale: en
meta:
description: "Niche score 44/100 · $103K/yr market · 42K searches/yr · $54.09 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:description": "Niche score 44/100 · $103K/yr market · 42K searches/yr · $54.09 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:title": "Shim Kit — $103K/yr Amazon US Niche (2026) - Flapen"
---
# **shim kit**
**Skip it**
Soft demand (-8.0% this quarter) — this niche doesn't clear our bar today.
Market size 25Growth 21Conversion 54Competition 52Returns 62Price range 39Avg price 92Brand share 36Review moat 93Quality gap 27
**Review moat**
**Great****144.32**
avg incumbent reviews — the moat a new listing must climb
**Avg price**
**Great****$54.09**
avg listing price — sweet spot $15–$100
**Returns**
**Good****2.5%**
return rate — above 5% kills the launch gate
**Conversion**
**Good****4.5%**
search→purchase rate — share of searches ending in a sale
**Competition**
**Good****54%**
top-5 click share — leaders hold, buyers still browse
**Price range**
**Okay****$10.03–$228.97**
cheapest to priciest tracked listing — scored on the share inside $15–$100
**Brand share**
**Okay****83%**
top-5 brand share — brands hold most of the demand
**Quality gap**
**Okay****4.6★**
avg incumbent rating — lower means beatable quality
**Market size**
**Okay****$103K**
$103K/yr · 42K searches
**Growth**
**Bad****-8.0%**
90-day search growth — must beat 0% to launch
**Signals**[** High Price**](https://flapen.com/research/niches?market=us&signal=high_price "Avg price > $50")
According to Flapen's Amazon United States niche tracking, shim kit is a $103K/yr Amazon United States market (42K searches/yr). The top 5 brands hold 83% of demand. Verdict: Skip it — 44/100.
Data updated Jul 9, 2026 · scored weekly · [~~How we score niches ~~](https://flapen.com/research/methodology)
## **shim kit market data**
- **Units sold / yr**
- **2K–2K**
- avg 0–100/product
- **Revenue / yr**
- **$81K–$108K**
- units × avg price
- **Conversion rate**
- **4.5%**
- **Avg BSR**
- **#127**
- **Page quality**
- **0%**
- **Prime**
- **96%**
- **Sponsored**
- **93%**
- **Out of stock**
- **0.6%**
- **Avg brand age**
- **58 months**
- **Avg seller age**
- **187 days**
## **Competition & brand share**
The top 5 products take 54% of clicks — established leaders, but buyers still shop beyond them.
**Brands**
**14 **—flat
**Sellers**
**38**
**Top-5 brand share**
**83%**
Top 20: 100%
**Top-5 click share**
**54%**
Top 20: 92%
**Open market**
**13%**
- Hot Cams40% - TACSHIM29% - MUYIDP6% - PROOTOM5% - Easily4% - GtohHavea3% - Open — no brand owns it (8 brands, 13%)
## **Demand & seasonality**
Weekly Amazon search volume, last 62 weeks — -8.0% search growth over the last 90 days.
800600Spike '25Spike '26 seasonMayJunJulAugSepOctNovDecJanFebMarAprMayJun
No pronounced peak months · busiest ÷ quietest = 1.4×
[**Open Trend **](https://flapen.com/research/us/automotive/shim-kit/trend)
## **Top shim kit search terms**
- **valve shim kit**12K/yr-3.2%2.5% conv. - **shim kit**11K/yr-5.6%1.8% conv. - **ar shim kit**6K/yr-37.2%9.4% conv. - **valve shims**5K/yr+25.3%1.0% conv. - **slotted shims**3K/yr+40.9%0.8% conv. - **hot cams shim kit**4K/yr-3.2%4.9% conv. - **barrel shims**3K/yr-16.7%12.8% conv. [**All search terms **](https://flapen.com/research/us/automotive/shim-kit/search-terms)
## **Top shim kit products on Amazon**
Each bubble is one product — market share against review moat; bubble size tracks estimated sales, color grades how beatable the incumbent looks.
0%5%$5K10%$10K15%$15K20%$21K1101001K Reviews — right = deep review moatMarket share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)
All 24 tracked products in this niche — three views at once, no toggling.
### **Top sellers**
by 90-day click share
[1**Hot Cams 7.48mm Complete Shim Kit HCSHIM01 for Honda CRF Kawasaki KX Suzuki RMZ Yamaha WR YZ Dirt Bikes**Hot Cams**$86.10**4.7★917 rev](https://www.amazon.com/dp/B000UKM6LG) [2**Hot Cams 9.48mm Complete Shim Kit HCSHIM02 for Arctic Cat DVX 400 ATV Honda TRX ATV Kawasaki KFX ATV Suzuki LT-R ATV Yamaha YFZ ATV Regular**Hot Cams**$81.89**4.6★918 rev](https://www.amazon.com/dp/B000UKHCM4) [3**TACSHIM Black 1/2x28 Barrel Shim Kit for .223 5.56 (14 Pack)**TACSHIM**$14.01**4.7★185 rev](https://www.amazon.com/dp/B0CY56H259) [4**47Pcs 7.48mm Valve Shim Kit for Honda CRF 250R/X Kawasaki KX 250F Suzuki RMZ 250 Yamaha YZ 250F WR 250F Dirt Bikes**MUYIDP**$27.95**4.6★92 rev](https://www.amazon.com/dp/B09NCS421T) [5**TACSHIM Black 5/8x24 Barrel Shim Kit for .308 7.62mm 300BLK .30 Cal (14 Pack)**TACSHIM**$14.04**4.7★134 rev](https://www.amazon.com/dp/B0CY5GKKM9)
**~~View all top sellers →~~**
### **Newest**
by launch date
[**100PCS 304 Stainless Steel Shim Kit 2 x 2 Slotted Assortment Box**Shark Tears**$87.78**31 rev1w ago](https://www.amazon.com/dp/B0G64MYG3F) [**304 Stainless Steel Shim Kit 100 PCS 2 x 2 Slotted Shims Assortment 10 Thicknesses for Machine Leveling Motor Alignment & Equipment Adjustment Laser-Marked Sizes with Storage Case**GtohHavea**$86.62**55 rev6mo ago](https://www.amazon.com/dp/B0GCDMH768) [**Shimeyao 80 Pcs Size A 2 x 2 Stainless Steel Slotted Shims Kit Composite Precision Metal Shims Stock for Leveling Assortment with Storage Box 8 or 13 Thicknesses for Machinist Motor Shop Wood Door**Shimeyao**$89.05**23 rev1y ago](https://www.amazon.com/dp/B0F93TJR43) [**TACSHIM Barrel Nut Shim Kit for .308 (16 Pack) MFR#10BN**TACSHIM**$13.05**40 rev1y ago](https://www.amazon.com/dp/B0DGH15M61) [**AWSZH Adjustable Valve Shim Kit 7.48mm Compatible with Honda CRF250X 2004-2017 Kawasaki KLX250 1979-1980 Suzuki TL1000S 1997-2001 Yamaha FZS600 FZ6 2004-2007 Yamaha YZF-R6 1999-2009 Dirt Bikes(47Pcs)**AWSZH**$33.22**3 rev1y ago](https://www.amazon.com/dp/B0D95G8GPL)
**~~View all new products →~~**
### **Trending**
90-day click momentum
[**304 Stainless Steel Shim Kit 100 PCS 2 x 2 Slotted Shims Assortment 10 Thicknesses for Machine Leveling Motor Alignment & Equipment Adjustment Laser-Marked Sizes with Storage Case**GtohHavea**$86.62**4.5★**▲ 249%**](https://www.amazon.com/dp/B0GCDMH768) [**AWSZH Adjustable Valve Shim Kit 7.48mm Compatible with Honda CRF250X 2004-2017 Kawasaki KLX250 1979-1980 Suzuki TL1000S 1997-2001 Yamaha FZS600 FZ6 2004-2007 Yamaha YZF-R6 1999-2009 Dirt Bikes(47Pcs)**AWSZH**$33.22**4.3★**▲ 172%**](https://www.amazon.com/dp/B0D95G8GPL) [**100PCS 304 Stainless Steel Shim Kit 2 x 2 Slotted Assortment Box**Shark Tears**$87.78**4.4★**▲ 150%**](https://www.amazon.com/dp/B0G64MYG3F) [**OTOM D9.48mm Thick 1.20-3.50mm Adjustable Valve Shim Kit for CRF450R CRF450X/RX YZ450F WR450F(141PCS)**PROOTOM**$66.78**4.7★**▲ 72%**](https://www.amazon.com/dp/B08KW13W9F) [**PlasmaGal - 1/2 x 28 Muzzle Shim Kit for .223 & 5.56 Calibers (20 Pieces) Stainless Steel Barrel Washers for Perfect Alignment (4 Units x 5 Thickness - 0.004/0.008/0.012/0.020/0.040)**PLASMAGAL**$11.86**4.6★**▲ 67%**](https://www.amazon.com/dp/B0CY9M8LFW)
**~~View all trending →~~**
## **What buyers say about shim kit**
What buyers praise and complain about, mined from review topics.
### **What buyers love **
**Quality-Overall**21%
*“Well manufactured kit”*
**Size-Overall**18%
*“Fits perfectly”*
**Advertised Vs Actual Product**15%
*“Works as advertised”*
**Value For Money**11%
*“Good Value”*
**Efficiency**5%
*“There are other uses for these”*
**Ease Of Use**5%
*“which is convenient”*
**Functionality-Overall**4%
*“Perfect for timing AR muzzle devices”*
**Thickness**3%
*“Thickness accurate”*
**Stiffness**2%
*“Shims work just as they should”*
**Compatibility-Overall**2%
*“Works perfect for AR”*
### **What buyers complain about **
**Thickness**21%
*“Thickness variations are noticeable”*
**Advertised Vs Actual Product**12%
*“Do not believe the description”*
**Size-Overall**12%
*“Does not fit all barrels”*
**Quality-Overall**10%
*“I was extremely disappointed with the quality control”*
**Adjustability/Rotatability/Reclining**8%
*“There is no way to adjust the shims because there is no way to make a”*
**Ease Of Use**4%
*“They are, however, a bit finnicky to use”*
**Compatibility-Overall**4%
*“WON'T WORK ON ITEMAS”*
**Assembly/Installation**3%
*“It bent easily during installation”*
### **Top return reasons **
**Size-Overall**53%
**Advertised Vs Actual Product**9%
**Defective Material/Parts**8%
**Compatibility-Overall**7%
**Value For Money**6%
**Functionality-Overall**3%
**Thin**3%
**Thickness**3%
**Ease Of Use**2%
**Quality-Overall**1%
## **Common questions**
- **Is shim kit profitable to sell on Amazon United States?**
- The niche generates $103K/yr across 28 tracked products. 3 of 4 products launched in the last 360 days are still selling. 90-day search growth is -8.0%. Flapen's verdict: Skip it (44/100).
- **How competitive is the shim kit niche?**
- 14 brands and 38 sellers compete. The top 5 products take 54% of clicks and top 5 brands hold 83% of demand.
- **What do buyers complain about in shim kit?**
- Top complaints mined from reviews: Thickness, Advertised Vs Actual Product, Size-Overall. The return rate is 2.5%.
- **When does demand for shim kit peak?**
- Demand is steady year-round — the busiest month runs 1.4× the quietest.
- **What does it cost to enter the shim kit niche?**
- Listings span $10.03–$228.97; the average listing price is $54.09 (sweet spot $15–$100). The average incumbent carries 144 reviews — the moat a new listing must climb.
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