Yz426 Rebuild

Discussion in 'Some Assembly Required' started by Scott Pryor, Oct 15, 2018.

  1. Scott Pryor

    Scott Pryor Been here awhile

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    Aug 1, 2015
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    113
    Location:
    MONTREAL, QC
    Hey Guys, im back at it again with another rebuild. In the past i rebuilt an old xv750 virago and a cx650e. Now im rebuilding my friends Yamaha yz426. He took the head and cyclinder off and than had it sitting in a bunch of boxes in his basement for about 2 years. Frustrated i took the project on. Ive got all the peices but ive never rebuilt a motor with a kickstart. Just looking for some tips. Is there anything i should look out for while rebuilding? Also should i rinse the crankcase out with some oil before starting? Il try and get some pictures up tonight.

    Thanks!
    #1
  2. r60man

    r60man Long timer

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    #2
    FR700 likes this.
  3. Scott Pryor

    Scott Pryor Been here awhile

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    Aug 1, 2015
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    113
    Location:
    MONTREAL, QC
    Yea it was because of some falkes of metal in the oil, he found the problem and fixed it but never bothered remounting it. Thats my job. Im going along with the manual though for the rebuild.
    #3
  4. bearcat1

    bearcat1 Been here awhile

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    Aug 27, 2006
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    Olympia, WA
    Three years ago I had an '01 426 that was brought back from almost dead. Be aware that the 426 cylinders and pistons have pretty much dried up. The solution is to go with the 450 parts if you need to go that route. I don't remember the details but you can gather all the info at the thumpertalk site. There's a lot of knowledge and helpful folks there concerning those old steel framed 400/426/450s. The YZ 426 is still a respectable bike, mine had a fly wheel weight and made a great trail bike. Good luck with the rebuild.
    #4
  5. bearcat1

    bearcat1 Been here awhile

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    Aug 27, 2006
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    Olympia, WA
    Because most of us like a picture:
    SAM_2110.JPG
    #5
    brucifer, FR700 and JagLite like this.
  6. mach1mustang351

    mach1mustang351 Long timer

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    May 12, 2014
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    Alaska
    I bought a 426 back in the day to replace my XR400 as a trail bike. What an impressive machine. It definitely was a better bike than I was a rider.
    #6