478 Big bore kit.

5 replies to this topic
  • A-10 Crewdog

Posted December 01, 2007 - 03:38 PM


I'm looking for someone who has installed an Athena 478 big bore kit. I have an 06 that I am going through which needs a new top end and was wondering what kind of unit the Athena was as far as fit, finish and reliability. I ride mostly in the forest with an occasional trip to the local m-x track and am looking for the best bang for the buck. Thanks much. Crewdog

  • yzf450jack

Posted December 01, 2007 - 05:21 PM


I have put one on a HoNdA and everything fit well, I uses a Wiseco Teflon coated piston ,It looks like the stock cylinder

  • yamaboy23

Posted December 02, 2007 - 07:25 AM


As for that kit,It was a great fit,and quality parts
Very good performance boost with stock cams
But if I had to do another,I might try a stroker crank with stock bore

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  • jeffboyd47m

Posted December 02, 2007 - 09:08 AM


I just rode and raced my new 08 Fri. and Sat. at a local indoor race. I installed the Athena kit with HotCams, DRD pipe and ZipTy carb mod. Wow! my bike runs incredible. I have never had a 4-stroke with the instant throttle response that this bike has. I had the ZipTy mod done on my 07 and it never ran this good. I can hardly wait to get this bike to a track that I can get it out of 3rd gear. For now I will have to wait for some snow to melt. I pulled several hole shots over the weekend (I raced in 3 classes both nights) and won all but 2 moto`s in the A class. This bike just flat out hauls butt! What I will probably do next is install a flywheel weight and go 2 teeth smaller on the rear sprocket. I also have a Rekluse Pro that I plan on installing.

  • SurvivorMan

Posted December 02, 2007 - 02:02 PM


let us know the dirties on the rekluse pro. what is the Zip Ty mod? i guess probably the BK mod.

  • grayracer513

Posted December 02, 2007 - 05:02 PM


what is the Zip Ty mod? i guess probably the BK mod.

Hardly. There is an AP mod done as part of the package, but the big thing is that the main air circuit is modified.

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