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Crankshaft AssembliesCrankshaft Assemblies

Dirt Bike Crankshaft Assemblies

Whether you’re in the process of a complete rebuild or just replacing a worn out part or two, proper maintenance is essential with every dirt bike engine. The crankshaft may not be the most glamorous component, but its proper functionality is vital. And when it’s that time, you know where to turn: Rocky Mountain ATV/MC!

If you prefer to replace the entire dirt bike crankshaft, we’ve got complete crankshaft assemblies for just the occasion. But if you just need to replace the motorcycle connecting rod (the piece that actually attaches the crankshaft to the piston), we’ve got those too. Regardless of your crankshaft needs, we’re the solution. (Please note that we also carry crankshaft bearings, but they are located on a separate page.)

When it comes to dirt bike crankshafts, two brands really stand out: Hot Rods and Pro X. We proudly carry both. Hot Rods crankshafts and connecting rods are known for their outstanding quality with a solid and loyal customer base. Pro X contracts with many of the same factories that build the OEM parts, so you know the lower price isn’t an indication of the part’s strength or durability. (Of course, if you prefer the actual OEM parts, we have those too.)

Regardless of your ride – YZ250, RM125, CRF250R or anything else – Rocky Mountain ATV/MC is your source for dirt bike crankshaft assemblies!

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

  • Wrench Rabbit Engine Rebuild Kit

    Wrench Rabbit Engine Rebuild Kit

    Kedrick in MI


    Awesome products and you can’t beat the price! I’d absolutely recommend this product and couldn’t beat the fast easy ordering and awesome shipping prices. Can’t wait to get my head in and finish this project up and hear her start up for the first time will continue to order parts threw Rockey mountain atv

    Read All Reviews
  • Wiseco Bottom End Rebuild Kit

    Wiseco Bottom End Rebuild Kit

    Justin in UT

    Not a bad setup, especially if you're on a budget.

    I have heard some good and some bad about these crank kits. I personally have not had a bad experience with them, and my current bike has one in right now and I have no issues.

    Read All Reviews
  • Hot Rods Bottom End Kit

    Hot Rods Bottom End Kit

    Bruce in WA

    Easy to navigate web site and fast delivery.

    Read All Reviews
  • Pro X Connecting Rod Kit

    Pro X Connecting Rod Kit

    Scott in OK

    2004 Suzuki RM125 (worked like a champ)!

    Pro-X parts are great, just got my 2004 Suzuki RM125 crank pressed (people are still around that do this). It is working perfectly, I also used the Pro-X Main Bearings (as well) working great!

    Read All Reviews
  • Hot Rods Complete Crankshaft Assembly

    Hot Rods Complete Crankshaft Assembly

    Steven in TX

    Great part

    I now have 110 hours on this crank in a crf450. Has performed perfectly. Just put a 3rd piston in & still no play in the lower end. Its as tight as it was when installed. No reason to think it wont go another 100 hrs. Im sure it will. I do change my oil about every 8-10 hours of run time & use motul 300v oil. Very happy with this part. Ive purchased one for my ktm 300. Also used hot rods bearings & seal with the crank.

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  • Hot Rods Complete Crankshaft Assembly  - Heavy Duty

    Hot Rods Complete Crankshaft Assembly - Heavy Duty

    Dana in MA

    $300 now or $800 later. Up to you.

    Don’t wait for it to let go. Tick tock tick tock. $$$$$$$$$$$

    Read All Reviews
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