---
title: "Honda Gx390 Spark Plug — $318K/yr Amazon US Niche (2026) - Flapen"
canonical_url: "https://flapen.com/research/us/automotive/honda-gx390-spark-plug"
last_updated: "2026-08-11T02:54:11.926Z"
locale: en
meta:
description: "Niche score 44/100 · $318K/yr market · 158K searches/yr · $9.97 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:description": "Niche score 44/100 · $318K/yr market · 158K searches/yr · $9.97 avg price. Doesn't clear our bar today. Data updated Jul 2026."
"og:title": "Honda Gx390 Spark Plug — $318K/yr Amazon US Niche (2026) - Flapen"
---
# **honda gx390 spark plug**
**Skip it**
Brand-locked demand (top 5 brands take 99% of clicks) — this niche doesn't clear our bar today.
Market size 52Growth 28Conversion 100Competition 25Returns 88Price range 50Avg price 33Brand share 4Review moat 73Quality gap 18
**Conversion**
**Incredible****20.2%**
search→purchase rate — share of searches ending in a sale
**Returns**
**Great****1.4%**
return rate — above 5% kills the launch gate
**Review moat**
**Good****599.29**
avg incumbent reviews — the moat a new listing must climb
**Market size**
**Good****$318K**
$318K/yr · 158K searches
**Price range**
**Good****$4.13–$25.69**
cheapest to priciest tracked listing — scored on the share inside $15–$100
**Avg price**
**Okay****$9.97**
avg listing price — sweet spot $15–$100
**Growth**
**Okay****+2.3%**
90-day search growth — must beat 0% to launch
**Competition**
**Okay****70%**
top-5 click share — leaders hold, buyers still browse
**Quality gap**
**Bad****4.7★**
avg incumbent rating — lower means beatable quality
**Brand share**
**Bad****99%**
top-5 brand share — brand-locked demand
According to Flapen's Amazon United States niche tracking, honda gx390 spark plug is a $318K/yr Amazon United States market (158K searches/yr). The top 5 brands hold 99% of demand. Demand peaks in Mar. Verdict: Skip it — 44/100.
Data updated Jul 11, 2026 · scored weekly · [~~How we score niches ~~](https://flapen.com/research/methodology)
## **honda gx390 spark plug market data**
- **Units sold / yr**
- **30K–40K**
- avg 1,500–2,000/product
- **Revenue / yr**
- **$299K–$399K**
- units × avg price
- **Conversion rate**
- **20.2%**
- **Avg BSR**
- **#104**
- **Page quality**
- **0%**
- **Prime**
- **100%**
- **Sponsored**
- **64%**
- **Out of stock**
- **0.0%**
- **Avg brand age**
- **45 months**
- **Avg seller age**
- **171 days**
## **Competition & brand share**
The top 5 products take 70% of clicks — established leaders, but buyers still shop beyond them.
**Brands**
**6 **▲rising
**Sellers**
**83**
**Top-5 brand share**
**99%**
Top 20: 100%
**Top-5 click share**
**70%**
Top 20: 100%
**Open market**
**0%**
- NGK60% - Honda17% - Hipa10% - Wetenex10% - TORCH2% - Yistiun1%
## **Demand & seasonality**
Weekly Amazon search volume, last 104 weeks — +2.3% search growth over the last 90 days.
8K6KSpike '24Spike '25Prime Day '25Holiday '25Spike '26 seasonSepDecMarJunAugNovMarMay
Peak months: Mar · busiest ÷ quietest = 2.1×
[**Open Trend **](https://flapen.com/research/us/automotive/honda-gx390-spark-plug/trend)
## **Top honda gx390 spark plug search terms**
- **ngk bpr6es**66K/yr+5.3%17.6% conv. - **bpr6es spark plug**29K/yr+16.5%19.4% conv. - **ngk bpr6es spark plug**29K/yr-12.7%20.2% conv. - **bpr6es**19K/yr-8.5%16.6% conv. - **honda gx390 spark plug**3K/yr+54.0%5.2% conv. - **spark plug ngk bpr6es**2K/yr+9.0%21.7% conv. - **honda gx160 spark plug**2K/yr+8.2%6.4% conv. - **ngk bpr6es spark plug 2 pack**2K/yr-13.1%27.6% conv. - **spark plug bpr6es**2K/yr+4.8%23.5% conv. - **ngk - bpr6es**2K/yr+3.5%16.4% conv. [**All search terms **](https://flapen.com/research/us/automotive/honda-gx390-spark-plug/search-terms)
## **Top honda gx390 spark plug 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%10%$32K20%$64K30%$95K40%$127K1101001K10K Reviews — right = deep review moatMarket share (90d) ≈ est. sales
Beatable (≤4.3★) Contested Strong incumbent (>4.7★)
All 14 tracked products in this niche — three views at once, no toggling.
### **Top sellers**
by 90-day click share
[1**New NGK Standard Spark Plug BPR6ES 7131 Set of 4 Spark Plugs**NGK**$15.48**4.8★621 rev](https://www.amazon.com/dp/B00WF9O3W0) [2**NGK (2 Pack) #7131 Spark Plug (2 Pack) # BDPR6ES-2pk**NGK**$9.91**4.7★150 rev](https://www.amazon.com/dp/B00FEQRD6Y) [3**BPR6ES NGK Spark Plug for Honda Engines & Other Small Engines (One Spark Plug)**NGK**$6.73**4.8★1,845 rev](https://www.amazon.com/dp/B00S7RZX28) [4**BPR6ES Spark Plug for NGK BPR6ES BP6ES Torch F6RTC MTD 951-10292 Honda 98079-56846 GX120 GX160 GX200 GX240 GX270 GX340 GX390 4 PACK**Wetenex**$10.85**4.5★125 rev](https://www.amazon.com/dp/B0DSVGK983) [5**Honda 2 Pack Genuine 98079-56846 Spark Plug Fits NGK BPR6ES OEM**Honda**$9.38**4.8★963 rev](https://www.amazon.com/dp/B01CXCHEJ2)
**~~View all top sellers →~~**
### **Newest**
by launch date
[**Yistiun BPR6ES Spark Plug for NGK 7131 for Torch F6RTC F6TC MTD 951-10292 951-10292A 751-10292 for Honda 98079-56846 for Champion RN9YC RN10YC GX120 GX160 GX200 GX240 GX270 GX340 GX390**Yistiun**$4.13**10 rev5mo ago](https://www.amazon.com/dp/B0GKYPC5L8) [**Hipa BPR6ES Spark Plugs Compatible with NGK 7131 Torch F6RTC MTD 951-10292 751-10292 Honda 98079-56846 Engines & Other Small Engines (Pack of 4)**Hipa**$9.50**7 rev8mo ago](https://www.amazon.com/dp/B0FY6HYXXM) [**BPR6ES Spark Plug for NGK BPR6ES BP6ES Torch F6RTC MTD 951-10292 Honda 98079-56846 GX120 GX160 GX200 GX240 GX270 GX340 GX390 4 PACK**Wetenex**$10.85**125 rev1y ago](https://www.amazon.com/dp/B0DSVGK983) [**TORCH F6RTC 131-039 Spark Plug Replace for NGK BPR6ES Spark Plug for Bosch WR6DC WR7DC Spark Plug for Champion RN9YC RN10YC Spark Plug for Denso W20EPR-U Spark Plug for MTD 951-10292/751-10292 OEM ea**TORCH**$6.01**1,503 rev4y ago](https://www.amazon.com/dp/B09S8DQ3JL) [**New NGK Standard Spark Plug BPR6ES 7131 Set of 4 Spark Plugs**NGK**$15.48**621 rev9y ago](https://www.amazon.com/dp/B00WF9O3W0)
**~~View all new products →~~**
### **Trending**
90-day click momentum
[**Yistiun BPR6ES Spark Plug for NGK 7131 for Torch F6RTC F6TC MTD 951-10292 951-10292A 751-10292 for Honda 98079-56846 for Champion RN9YC RN10YC GX120 GX160 GX200 GX240 GX270 GX340 GX390**Yistiun**$4.13**4.5★**▲ 194%**](https://www.amazon.com/dp/B0GKYPC5L8) [**Hipa BPR6ES Spark Plugs Compatible with NGK 7131 Torch F6RTC MTD 951-10292 751-10292 Honda 98079-56846 Engines & Other Small Engines (Pack of 4)**Hipa**$9.50**5.0★**▲ 161%**](https://www.amazon.com/dp/B0FY6HYXXM) [**98079-56846 (NGK BPR6ES) Honda Genuine OEM Spark Plug Honda & Other Small Engines**Honda**$7.22**4.6★**▲ 99%**](https://www.amazon.com/dp/B00WIZG9EG) [**NGK (2 Pack) #7131 Spark Plug (2 Pack) # BDPR6ES-2pk**NGK**$9.91**4.7★**▲ 25%**](https://www.amazon.com/dp/B00FEQRD6Y) [**Honda 2 Pack Genuine 98079-56846 Spark Plug Fits NGK BPR6ES OEM**Honda**$9.38**4.8★**— 7%**](https://www.amazon.com/dp/B01CXCHEJ2)
**~~View all trending →~~**
## **What buyers say about honda gx390 spark plug**
What buyers praise and complain about, mined from review topics.
### **What buyers love **
**Socket/Port/Plug**20%
*“Great plugs and easy order & delivery”*
**Quality-Overall**20%
*“Great product, Great company”*
**Value For Money**17%
*“Great value”*
**Advertised Vs Actual Product**14%
*“As advertised”*
**Size-Overall**13%
*“Exact fit”*
**Assembly/Installation**3%
*“Easy to install”*
**Ease Of Cleaning**2%
*“Runs clean and after a year of sitting the mower started first pull”*
**Motor Power**2%
*“Engine runs like a new one”*
**Efficiency**2%
*“Works good”*
**Durability**1%
*“And its durable”*
### **What buyers complain about **
**Advertised Vs Actual Product**14%
*“A little misleading”*
**Socket/Port/Plug**14%
*“Both plugs failed within minutes”*
**Durability**12%
*“These simply do not last very long”*
**Functionality-Overall**11%
*“Function poor”*
**Ease Of Use**9%
*“it was hard to start”*
**Size-Overall**9%
*“Didn't fit my spark plug cap”*
**Product Condition**5%
*“received someone elses used return”*
**Natural Resource Wastage**5%
*“Waste of time”*
**Value For Money**3%
*“Not worth the money”*
### **Top return reasons **
**Size-Overall**58%
**Compatibility-Overall**10%
**Advertised Vs Actual Product**10%
**Defective Material/Parts**6%
**Socket/Port/Plug**5%
**Functionality-Overall**4%
**Value For Money**3%
**Assembly/Installation**1%
**Heating**1%
**Motor Issues**1%
## **Common questions**
- **Is honda gx390 spark plug profitable to sell on Amazon United States?**
- The niche generates $318K/yr across 14 tracked products. 0 of 2 products launched in the last 360 days are still selling. 90-day search growth is +2.3%. Flapen's verdict: Skip it (44/100).
- **How competitive is the honda gx390 spark plug niche?**
- 6 brands and 83 sellers compete. The top 5 products take 70% of clicks and top 5 brands hold 99% of demand.
- **What do buyers complain about in honda gx390 spark plug?**
- Top complaints mined from reviews: Advertised Vs Actual Product, Socket/Port/Plug, Durability. The return rate is 1.4%.
- **When does demand for honda gx390 spark plug peak?**
- Demand peaks in Mar; the busiest month runs 2.1× the quietest.
- **What does it cost to enter the honda gx390 spark plug niche?**
- Listings span $4.13–$25.69; the average listing price is $9.97 (sweet spot $15–$100). The average incumbent carries 599 reviews — the moat a new listing must climb.
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