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Crankshaft AssembliesCrankshaft Assemblies

ATV Crankshaft Assemblies

If you have a seized engine, or are looking to overhaul or rebuild your engine, don’t forget to replace your crankshaft. Crankshafts rarely break, but considering that they are such a major component of your bottom end, they can cause a lot of damage if they do. At Rocky Mountain ATV/MC, we carry durable, quality crankshafts to get your engine running strong again in no time.

We carry full crankshaft assembly kits and connecting rod kits that are built to OEM specifications and designed to meet or exceed OEM performance. Our kits from Hot Rods and Pro-X are designed to last the lifetime of your ATV when properly cared for.

If you would like a stock crankshaft instead, be sure to check out the OEM section of our website to get the original manufactured crankshaft and any additional accessories that you may need. Check out our selection of crankshaft and connecting rod kits for your ATV today!

Latest ATV Crankshaft Assemblies Reviews – You could win up to $500 for reviewing products!

  • Wiseco Bottom End Rebuild Kit

    Wiseco Bottom End Rebuild Kit

    Stephen in TX

    12 hours after use

    2003 KX250 rebuild I bought this rebuild kit because I had an interior seal seaping into the combustion chamber and you have to split the case to change it. This caused a very low end bog off throttle. PROS- it works fantastic so far. I am about 12 hours into it. It’s cheap! Make sure you know what your doing though. CONS- As other reviews have said two gaskets did not fit correctly and were unusable. This is subpar quality compared to OEM. Gaskets are paper and crank uses plastic where aluminum there before. I believe this has been stated by previous reviews. There were two gaskets

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  • Hot Rods Bottom End Kit

    Hot Rods Bottom End Kit

    D. Paul in IN

    When you gotta have it

    First race on 2/17, delivered the power as needed. We will see how it stands up for the season...look forward to a great season in 2018.

    Read All Reviews
  • Yamaha Wide Ratio Transmission Kit

    Yamaha Wide Ratio Transmission Kit

    Juan in P.R.

    great modification to my bike

    now I can run with those enduro bikes, with out overdraw my engine. this wide ratio it's great.

    Read All Reviews
  • SDI Motor Mount Plate

    SDI Motor Mount Plate

    joseph in MI

    Great product

    Extra support to make sure after alignment it stays put! If your motor has the holes tapped super easy if not just drill and tap then no biggie worth it

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  • Hot Rods Connecting Rod Kit - Heavy Duty

    Hot Rods Connecting Rod Kit - Heavy Duty

    JERRY in MN


    good product, worked well, good price, cheaper than a whole crank

    Read All Reviews
  • Hot Rods Complete Crankshaft Assembly

    Hot Rods Complete Crankshaft Assembly

    Tyler in OH

    No complaints

    I have installed these in well over 15 different 2 and 4 stroke bikes and have never had any problems with any of them. Recommended

    Read All Reviews
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