Results 1 to 5 of 5

Thread: 400ex Head stud repair how-to

  1. #1
    Join Date
    Jan 2007

    400ex Head stud repair how-to

    Here's a how-to I put together on repairing pulled out studs. There is some mis-information out there if you search, but I assure you that they are 10 x 1.25 pitch.

    I used these inserts that I got from Fastenal. I've talked to guys who say that helicoils are fine, but I liked these better.

    I also picked up the tap and 31/64 bit I needed while I was there. I got everything for around $40.

    First we measured the depth of the existing threads so we'd know how deep to drill.

    Then we marked our depth on the drill bit with a piece of tape so we'd know where to stop.

    Next, we drilled the holes. Mine is a 440, so the holes were right next to the sleeve. You have to go really slow to make sure that the sleeve doesn't push the bit into the aluminum. Get it close, and then when you start drilling it will center itself on the existing hole. I have had guys tell me that they've drilled them with the jug on the bike using a cordless drill, but I already had mine off so we used the drill press.

    Tap the holes, being sure to use plenty of Tap Magic.

    The inserts came with some thread locker already on them, but we wanted to make sure they didn't come out.

    Thread the inserts in. They go into the tapped holes easy.

    There are slots on the top of the inserts that you can use a large screwdriver in to tighten them down.

    That's it. It's pretty easy, really. Take your time and there isn't much to it.
    2008 700xx - Two Brothers slip-on, K&N, Pro Armor bumper & nerfs, L8ton Racing sway bar, HIDs

    2000 400ex - 440 12.5:1 Wiseco, K&N, LRD full exhaust, HIDs

    2008 RZR - +5 long travel, Afco shocks w/ Progressive springs, Two Brothers slip-on, Two Brothers Juice Box, Donaldson intake, Dynatek ignition

    2007 BMW 335i - Burger Motorsports juice box 3 at 14psi, K&N dual intake

    1994 Mitsubishi GSX - Too much to list. 420awhp, 7.7 @ 96mph 1/8th mile

  2. #2
    Join Date
    Aug 2008
    Central NJ
    this needs to be a sticky or added to the faq, great info!

  3. #3
    Join Date
    Feb 2008
    Orange County, Ca.
    Originally posted by CJM
    this needs to be a sticky or added to the faq, great info!

  4. #4
    Join Date
    May 2010
    What is a 'head stud' and what's the purpose of them?

  5. #5
    Join Date
    Apr 2005
    Sticky added! This is a great thread also. steve
    2019 Maverick X3 XDS Turbo R
    2003 TRX 400EX

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts