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Stirlingkit RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini Chopper Bike Motorcycle
Stirlingkit RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini Chopper Bike Motorcycle, view 2Stirlingkit RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini Chopper Bike Motorcycle, view 3Stirlingkit RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini Chopper Bike Motorcycle, view 4Stirlingkit RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini Chopper Bike Motorcycle, view 5Stirlingkit RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini Chopper Bike Motorcycle, view 6
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RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini Chopper Bike Motorcycle

$849.99–$899.99Save up to 6%

In stock at stirlingkit.com

The RETROL R29 is a 1/5-scale 4.2cc V-twin gasoline engine modeled on the 1970s Knucklehead motorcycle engine. It's air cooled, built from brass and stainless steel, and mounted on a wooden base with start and ignition equipment so it's ready to run. Prices run $849.99 to $899.99 in silver or black.

Shop now at Stirlingkit →Code start

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Color
Silver · Black

Price and stock from stirlingkit.com, refreshed daily. We may earn a commission if you buy.

Highlights

  • 4.2cc V-twin, four-stroke, OHV
  • Styled after the Knucklehead engine
  • 1/5 scale, brass and stainless steel
  • Ready to run with start and ignition gear
  • Wooden display base

Best for

Motorcycle and engine collectors who want a running mini Knucklehead.

Things to consider

  • Carburetor needle may need adjusting to start.
  • Burns gasoline; use proper ventilation.
  • Black and silver differ in price.

Key specs

Price$849.99–$899.99
Displacement4.2cc
TypeV-twin, four-stroke gasoline
Scale1/5
MaterialBrass, stainless steel
ColorsSilver, Black

Our take

A beautifully detailed running Knucklehead miniature.

RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini… at a glance

BrandStirlingkit
Price$849.99–$899.99 (some options up to 6% off)
Typev twin engine
Options2 colors
AvailabilityIn stock at stirlingkit.com
Couponstart
ReturnsThe about page lists a 30-day return or exchange. All returns need an RMA requested via…

Price check

At $849.99, the RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini… is toward the top of Stirlingkit's price range, whose 2,729 listed products run $0.54 to $11,000.

Some options are on sale, up to 6% below their listed price; the discount depends on the option you choose. Sale prices can end without notice, so check the live price before you order.

Similar items from other brands we track run $15 to $95.

Buying from Stirlingkit

Stirlingkit is a good source for hobbyists who want running miniature engines, Stirling and steam models, and build kits that most toy stores never carry. Skip it if you need fast, cheap returns, since everything goes through an emailed RMA to a Shenzhen address. Check the shipping method and warehouse at checkout first, because airmail can take 15 to 35 business days.

Shipping
Airmail takes 15 to 35 business days, EMS 5 to 8, and DHL Express 3 to 7. Shipping fees vary by product, warehouse, and destination and show on each product page and at checkout.
Returns
The about page lists a 30-day return or exchange. All returns need an RMA requested via service@stirlingkit.com, and items must include original packaging and accessories with no physical damage.
Warranty
The about page lists a 1-year warranty and lifetime customer support.

Read our full Stirlingkit review and shop all products →

Frequently asked questions

Is the RETROL R29 ready to run?
Yes, it ships ready to run with start and ignition equipment.
What engine is it based on?
The listing says it's based on the 1970s V-twin Knucklehead motorcycle engine.
Is the RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini… on sale?
Yes, some options are discounted, up to 6% off; it currently sells for $849.99–$899.99. The exact saving depends on the option you pick, so check it on stirlingkit.com.
Is there a coupon code for the RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini…?
Stirlingkit's store-wide code start can be entered at checkout on stirlingkit.com. Stirlingkit sets the discount, and some items or sale prices may be excluded.
What is Stirlingkit's return policy?
The about page lists a 30-day return or exchange. All returns need an RMA requested via service@stirlingkit.com, and items must include original packaging and accessories with no physical damage.
How long does Stirlingkit take to ship?
Airmail takes 15 to 35 business days, EMS 5 to 8, and DHL Express 3 to 7. Shipping fees vary by product, warehouse, and destination and show on each product page and at checkout.
Does the RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini… come with a warranty?
Stirlingkit's published warranty terms: The about page lists a 1-year warranty and lifetime customer support.
What options does the RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini… come in?
Color: Silver, Black.
Where can I buy the RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini…?
The RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini… is sold directly by Stirlingkit on stirlingkit.com. The Shop now button on this page goes straight to the product there, and code start can be applied at checkout.
Is the RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini… in stock?
Yes. Stirlingkit lists it as in stock on stirlingkit.com as of our latest check. Stock and prices refresh throughout the day.
Is Stirlingkit a legit store?
Stirlingkit is a good source for hobbyists who want running miniature engines, Stirling and steam models, and build kits that most toy stores never carry. Skip it if you need fast, cheap returns, since everything goes through an emailed RMA to a Shenzhen address. Check the shipping method and warehouse at checkout first, because airmail can take 15 to 35 business days. Our full Stirlingkit review covers shipping, returns and what to check before ordering.
Is the RETROL R29 4.2CC Miniature V-Twin Engine Motor OHV for Mini… expensive?
At $849.99 it is toward the top of Stirlingkit's range ($0.54 to $11,000 across 2,729 products), and similar items from other brands run $15 to $95.

More from Stirlingkit

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