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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!

  • Hot Rods Bottom End Kit

    Hot Rods Bottom End Kit

    Hayden in GA

    Heavy duty!

    Great product. Looks very well constructed. Hope to get many hours of run time out of this build. Just wish the kit came with the bearings for the transmission as well.

    Read All Reviews
  • Wiseco Bottom End Rebuild Kit

    Wiseco Bottom End Rebuild Kit

    Raymond in CA

    Can't go wrong with Wiseco

    Great rebuild kit, has everything needed to do the job, as a mechanic I've been getting these kits for years, and it's a pretty good price.

    Read All Reviews
  • Pro X Connecting Rod Kit

    Pro X Connecting Rod Kit

    Eric in CO

    High quality

    Used as replacement for OEM part, works perfectly with no issues, must be good my engine builder won't let me buy junk!

    Read All Reviews
  • 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
  • Hot Rods Complete Crankshaft Assembly

    Hot Rods Complete Crankshaft Assembly

    Darrell in FL

    Good Quality at a good Price

    After a bolt in the bottom end worked it's way loose and destroyed my crankshaft it was time for a total engine rebuild. Bought this crank shaft with the hopes that the lower price didn't mean lower quality. The crank came in spec per the Yamaha manual and fit without problems. The construction and materials used seem to be solid and so far have no issues on about 20 hours of run time. Time will tell if it holds up, so far it's been a great buy.

    Read All Reviews
  • Wrench Rabbit Engine Rebuild Kit

    Wrench Rabbit Engine Rebuild Kit

    paul in NM

    Very impressed

    Great product and fast shipping has everything needed to complete the job well done for sure.

    Read All Reviews
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