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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 Complete Crankshaft Assembly

    Hot Rods Complete Crankshaft Assembly

    mike in UT

    Nice Quailty

    I have now used two of the cranks. one a CfR150R and CR500AF. Both cranks have had excellent quality. Both have run great. I am really impressed by the way they run.

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  • Hot Rods Bottom End Kit

    Hot Rods Bottom End Kit

    DANIEL in OR

    great kit, priced right

    I installed this in a blown 2001 yz250f. the 03 and up spec crank is a great upgrade for the weak 01-02 bottom ends. Bigger crank pin is far more durable. (you will need an 03 up flywheel and flywheel nut if you plan on dropping in an 01-02). This kit is great. measured runout was less than .001" and factory allows for up to .002". not bad for a mass produced crank from Taiwan. What's the difference between Taiwanese products and some made in China, Quality Control. Taiwan has good QC; China not so much. the components of this kit all are of high quality. rod stamped made in U.S.A., vertex gaskets, Taiwanese main bearings, and KSF (I think? cant remember) oil seals. the only beef I have with this kit is that the O-rings for the oiling sytem passage ways seemed thinner than OEM so I re-used the OEM ones as I thought they would seal better. had I known that before I would have ordered new OEM O-rings when I ordered this kit. (there's your notice would-be buyer) Overall a very high quality kit with no issues. So far, I have over ten hours on this kit and expect to get lots more. Hot rods kits are all high quality priced right! they are the only kits I will buy from now on.

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  • Hot Rods Complete Crankshaft Assembly  - Heavy Duty

    Hot Rods Complete Crankshaft Assembly - Heavy Duty

    JEROME in QC

    good cheap and simple

    good thing to put, brand new all at once...!

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  • Pro X Connecting Rod Kit

    Pro X Connecting Rod Kit

    NATHAN in MO

    TRX250R PRO-X ROD

    IF YOU HAVE A TRX250R AND NEED A NEW CONNECTING ROD AND LOWER ROD BEARING, THIS IS THE KIT THAT YOU WANT TO BUY. BEARING AND ROD ARE MADE OF HIGHER QUALITY STEEL THAN THE HOTROD'S KIT OR ANY OF THE EBAY BRANDS. THIS ROD AND BEARING IS MADE IN JAPAN, AND SUPPOSEDLY IN THE SAME FACTORY THAT PRODUCED THE OEM HONDA RODS BACK IN THE 80'S.

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  • Hot Rods Connecting Rod Kit - Heavy Duty

    Hot Rods Connecting Rod Kit - Heavy Duty

    Lucas in CO

    Good product

    You cant go wrong when buying a Hot Rods product. Just out of the box you can tell the quality of their work. Fit perfectly and is still running strong!

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  • Hot Rods Connecting Rod Kit

    Hot Rods Connecting Rod Kit

    AARON in WA

    Well Made Kit!

    this is a very good product. my rod lower end was getting loose so i ordered this kit. it even came in a very nice little plastic case, not a bag! all items need to replace the rod came with it, i did not have to order anything else from the dealer.

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