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compression

  1. 400ex low compression

    TRX General Discussions
    I just bought a 2002 400ex for $1450. It started, idled fine with choke to start it. Then it idled fine after. I let it warm up, then shut off the gas. I plugged the compression gauge in and put it full throttle, then let it crank. It only showed 90psi. So it's low. But it starts easy and no...
  2. New guy, Help please

    New Member Introductions
    How's it going guys, new to the forum but not so much to riding. I've been riding for just about two years now but just a few months ago i started buying broken, rebuilding, and reselling but i've run into a nasty bump on this one. It's an '01 250ex. I had to rebuild the entire engine end...
  3. 400ex heavy duty stud

    Maintenance / Important Information
    i got a 400ex with 30 for compression. the first ring was stuck close. idk why but w.e so i figured since i got it apart. i bought a wiseco 11:1 piston 86mm. nothing crazy. im a bigger kid and i heard that going higher compression you will blow head gaskets alot. so should i just invest in the...
  4. 400ex question.

    Engine/EFI/Drivetrain
    i have a 400ex it has has 30 for compression. the cylinder wall has no scratches and looks good. its the stock piston in it. i noticed the first ring it collapsed or just stuck shut the other one isnt. should i just change the rings. or just oem piston and rings and change it or get it bored out...
  5. honda 400ex has very low compression

    TRX General Discussions
    i bought a 400ex figured it needed a new top end. did a compression test it only has 30 for compression. i put a tiny amount of oil into the cylinder. did nothing put more into it. it went up to like 60 70. so i started taking it about. i ended up finding out it has paper stuffed into the intake...
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