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05+ TRX 400EX 400X Complete Rebuilt Bottom End Engine Rebuild Kit 87mm Piston


Compatible Vehicles
Submodel Year Make Model
TRX400EX 2x4 2008 Honda Sportrax 400
TRX400EX 2x4 2007 Honda Sportrax 400
TRX400EX 2x4 2006 Honda Sportrax 400
TRX400EX 2x4 2005 Honda Sportrax 400
2x4 2014 Honda TRX400X
2x4 2013 Honda TRX400X
2x4 2012 Honda TRX400X
2x4 2009 Honda TRX400X
  • Wiseco or Hotrods heavy duty crank with rod**
  • Wiseco or Hotrods crank bearings
  • Wiseco CP or JE 87mm forged hi comp pump gas piston**
  • Piston rings
  • Wristpin
  • Circlips
  • Complete gasket kit**
  • Seal kit
  • Valve stem seals
  • Heavy duty cam chain conversion
This is a bolt on kit that requires no machining of any kind.  Runs on pump or race gas.  All parts are new in the original packaging, and the original manufacturers' warranties apply*.


**The parts we sell come from the best names in the industry like, CP, JE, Wiseco, and Wossner pistons as well as Cometic, Vertex, Athena, and OEM gaskets.  We stock the exact same parts from all of these manufacturers because Covid is(and will be for the foreseable future) causing back orders on a daily basis.  When this happens we have a part that is the same quality to send instead of making the customer wait or having to cancel their order.  This is the ONLY reason your order may arrive slightly different from what you expect.  We NEVER sub out a good, quality part for a lower quality one without contacting you first to get approval.  If you have any questions about this or if you only want a certain brand part just contact us!

*This kit is NOT DIY.We recommend that this kit be installed by a qualified, experienced mechanic.  Warranty does not include any failure that is a result of improper installation, improper tuning, improper break in, or misuse.  Piston comes with specific instructions for setting the ring gap.  If you do not follow these exactly your motor will fail.  99% of warranty claims we get are solely due to the ring gap not being set properly on the piston.  For any warranty to be considered the part(s) in question, along with an invoice from a professional mechanic for the build, must be sent to us and possibly the manufacturer for inspection.  We can not warranty parts based on photos, emails, phone calls, or another mechanic's assessment alone.