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AMSOIL 10W-40 100% Synthetic Dirt Bike Oil

Product code : DB40QT-EA

5 star rating Read 186 reviews

Customer Rating

5

95% would recommend

  • 5 184
  • 4 1
  • 3 1
  • 2 0
  • 1 0

AMSOIL 10W-40 100% Synthetic Dirt Bike Oil

5 star rating Based on 186 reviews
  • 5 star rating
    Smooth as Silk
    By  WILLIAM,  a  Verified Buyer  from  North Carolina  on  May 24, 2026
    I was running MAXIMA 10-40w 4 stroke...With this 06 yz450 has a Problem from shifting from Third to Fourth when RPM`s are high...Its common with 06,07.....But did some researching...Had a Motocross Racer suggest running AMSOIL 10w-40 weight for better low friction from Third to Fourth.....So far Hauling Ass....Thanks # 007
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Atv
    By  PAUL,  a  Verified Buyer  from  Caledon Canada   on  May 18, 2026
    Fantastic oil my Honda ATV ran so smoothly after using this oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great Oil
    By  KYLE,  a  Verified Buyer  from  UT  on  April 28, 2026
    I have run this oil in all my bikes for several years and no complaints at all, all valves stay within spec etc no clutch concerns and do like the clutch feel with the oil.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil
    By  PETE,  a  Verified Buyer  from  Pennsville, New Jersey  on  April 17, 2026
    AMSOIL who is the best I use it in my XR 250 R Honda my Honda four wheeler and all my Harley’s the only drawback is that it’s very expensive I would run it in my Ford 7.3 diesel but that takes 15 quarts would cost over $200 for oil that’s just too much.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    10W-40 dirt bike oil
    By  RYAN,  a  Verified Buyer  from  Pennsylvania   on  March 07, 2026
    Great product, been using this on a 2024 Honda CRF150R since new. Changed regularly due to racing the bike. Seems to hold up very well. Will continue to use it.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Dirtbikes
    By  BRAD,  a  Verified Buyer  on  February 24, 2026
    We use it in all of our 2 strokes transmissions..keeps the clutch feeling new, and have not had a single issues since we started using this product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Dirt Oil for dirt bikes
    By  JOHN,  a  Verified Buyer  from  Wisconsin   on  January 02, 2026
    I use Amsoil Dirt 10W-40 in my 2024 Honda CRF450, changing every 5 hours. No issues in two years of riding , 75 hours total. This oil adds to the dependability of my bike allowing me to concentrate on my riding, great product!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil for 4- stroks
    By  JERRELL,  a  Verified Buyer  from  Canton GA  on  November 16, 2025
    Transmission shifts better
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Don't trust anything else
    By  JOSH,  a  Verified Buyer  on  November 05, 2025
    This is the only oil I put in my dirt bike
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    05 klr 250
    By  JEREMY,  a  Verified Buyer  from  Colorado  on  October 05, 2025
    My dad picked up a 05 KLR 250 in decent shape still from a Farmer. After running Amsoil in a few different bikes of my own, I suggested Pops do the same. With 1800mi on the speedo, and just poking around the woods with it, should last a long time. Amsoil can't turn back the clock, but if it's in good shape, low miles and plan on keeping it. Its a great product to use.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil motorcycle oil
    By  Traveler ,  a  Verified Buyer  from  Idaho Falls, Idaho  on  August 26, 2025
    I have used Amsoil products on several vehicles and motorcycles for decades with excellent results. My newest motorcycle will also use Amsoil 10-50 Dirt Bike oil as this is the recommended oil viscosity. Highly recommend Amsoil for vehicles that are valued.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    The Best for my Adventure Bike
    By  DAVID,  a  Verified Buyer  from  Sammamish, WA.   on  August 04, 2025
    I use this in my KTM 890R Adventure bike and have not seen the camshaft issues others have seen. I am now on 5k and am a professional mechanic. I keep a close eye on my maintenance and cannot recommend this product enough!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Good even for 2 strokes
    By  DAVID,  a  Verified Buyer  from  Sammamish, WA.   on  August 04, 2025
    I use this in my ultra rare and valuable Vintage Racing 2 stroke motorcycles as well as my modern 4 stroke Dual Sport bikes. No clutch slippage or bearing issues ever!
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Oil and Service review.
    By  RYAN,  a  Verified Buyer  from  Utah  on  July 29, 2025
    I love the 10/50 oil..As a longtime original customer the only thing I really see is this...Amsoil use to send all there customers members hats,tshirts,stickers etc etc..Now all they have done is raise prices,charge delivery fees.I get theres costs etc etc for running a business..But never forget about your customers..The little things MATTER.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    2016 KTM 250sx with slavens big bore
    By  KTM,  a  Verified Buyer  from  Idaho  on  July 06, 2025
    Used this in my two stroke used on hard enduro single track trails lots of up hill climbs tree roots and loose rock, I use a aftermarket recluse clutch kit and this keeps it working like new even in a lot of hard clutching climbs with full power, also keeps the bike shifting smooth
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best oil for my Honda
    By  SEAN,  a  Verified Buyer  from  Portland OR  on  June 18, 2025
    Ive ran strictly Amsoil Dirt in my drag Trx450r (500cc) that makes 3x the oem power using oxygenated vp fuel. Over 100hrs of abuse. The motor hasn't skipped a beat. I believe its in large part thanks to Amsoil Dirt.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Amsoil for 2 stroke crank case.
    By  MICHAEL,  a  Verified Buyer  from  Va  on  June 04, 2025
    I use Amsoil Dirt in all my 2 Strokes and it holds up in single trac very well.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Great oil, good price and quick shipping.
    By  BRIAN,  a  Verified Buyer  from  Barrie  on  May 21, 2025
    Great product
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    125cc Dirtbike
    By  JOVAN,  a  Verified Buyer  from  Niles, IL  on  May 20, 2025
    What a difference!. Feels better than before. Less smoke, more power. Doesn't burn as much oil as previous oil brand.
    Bottom Line
    Yes, I would recommend this to a friend.
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  • 5 star rating
    Best dirt oil out there!
    By  JUSTIN,  a  Verified Buyer  from  Kansas  on  May 12, 2025
    Not a better oil for your quad or bike than amsoil. I have bun running for years and love it!
    Bottom Line
    Yes, I would recommend this to a friend.
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