LC4 Steering head bearing, a how-to-guide...

Discussion in 'Thumpers' started by laramie LC4, Sep 15, 2006.

  1. DolphinJohn

    DolphinJohn Caveman

    Joined:
    Mar 17, 2007
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    4,039
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    Nature Coast, Florida
    Got everything apart and went to take off the cap and it's bigger than a 27.

    Went out to Sears and got a 30mm, too small!

    I'm going back for a 32 or larger, has anyone else had a larger cap on their LC4?


    .
  2. Tseta

    Tseta Lost

    Joined:
    Nov 30, 2008
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    760
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    On the road
    The '98 and '03 LC4's in our garage have caps with 27mm wrench flats, the '07 LC4 on the other hand has a cap with 32mm wrench flats.

    -T
  3. laramie LC4

    laramie LC4 flying something...

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    2,924
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    Tucson, Az
    should be a tool in your kit for this.....same one you use for the axle nut.

    laramie :beer
  4. DolphinJohn

    DolphinJohn Caveman

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    I have a Motion Pro 27mm for my axle nut, this was a 32mm.

    or did you mean one of these? :D

    [​IMG]

    .
  5. wrk2surf

    wrk2surf on the gas or brakes

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    I can find both the above stated wrenches.. but I can never find the sprocket bolt tool.. and the bottle opener :freaky
  6. DolphinJohn

    DolphinJohn Caveman

    Joined:
    Mar 17, 2007
    Oddometer:
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    Location:
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    I bought this bike used and didn't get the tool kit with it.

    I just checked my kit from my 250 and that tool you spoke of is indeed in there. 27 with a shallow 32 built in.

    Oh well, I think Sears will let me return the socket, I don't expect to have a use for it in the future.............


    My bearings were ok but there was not much grease left at all so I think I got in there just in time.

    Thanks for the help. I'm going to change my fork oil while they are off, then dive into the swingarm.


    .
  7. Highjnx

    Highjnx Serious Orange Crush

    Joined:
    Jan 25, 2010
    Oddometer:
    65
    Location:
    Seattle, WA
    I'm adding my thanks to Laramie for the how-to-guide, and adding a couple of pieces of advice to this process.


    I was putting on a BRP triple clamp and probably wouldn't have though to check this otherwise. My bike had smooth steering and no play at all. Now I'm going to take all of my KTM's apart and do the preventive if not corrective measures. This was an 05' with 14k on it that came from Carmel. It's amazing the corrosion this bike has from being near the salt air.

    [​IMG]

    The local bearing house had the SKA bearing for $20.00. However when it arrived it didn't have the outer race. With all the dicking around I think it would have been easier to have gone to KTM and gotten the part for $33.00.

    The hardest part of the job was removing the lower race from the frame, and the old bearing from the steering stem.

    The race proved to be easy once I found the right tool. Looking down through the frame stem there was about 1mm of race exposed on all sides. I started using a punch but found there wasn't enough purchase. I then took out a bar clamp and used the long flat metal bar. The two rectangular ends of the bar worked great giving two contact points on the race with each blow of the hammer.

    I found that the shaft could be pressed off the triple clamp which pushed the bearing off at the same time. Any cycle dealer can do this for you - how much they want to charge is another issue. Alternative is to pry up the outer bearing cage with a screwdriver and break it off. Place the triple clamp in the vice, heat up the remaining bearing with a solder torch for 30 seconds. Take a hammer and chisel work one side of the bearing shaft then flip over the triple clamp and work the other. Within a couple of minutes it's worked itself off.

    Getting the bearing on was a great example of physics. After cleaning up the steering stem with 000# steel wool, I placed the entire stem in the freezer for a couple of hours. I took it out and placed cooking oil from the kitchen on the lower portion of the shaft, and stood it upright. I wanted something with a fairly low burn point. Next I heated up the bearing with a small propane solder torch for about 45 seconds. I literally slid the bearing on the shaft and it dropped all the way to the bottom. No driving necessary.

    This was beyond easy, and I was patting myself on the back until I realized it was facing the wrong way...:huh
  8. meat popsicle

    meat popsicle Ignostic

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    :lol3 :cry

    nice additions to the thread :beer
  9. eskimojoe

    eskimojoe they call me badger

    Joined:
    Feb 25, 2007
    Oddometer:
    11
    Location:
    Sask,Canada - between a midlife crisis and pension
    Just finished my steering stem bearings on 2006 640 ADV. Bottom bearing was good and top was pitted and rusted. Timken bearing number for the set is L45449 and L45410. Cost $13.00 canuck bucks.
  10. wrk2surf

    wrk2surf on the gas or brakes

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    Oddometer:
    8,711
    Location:
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    Bringin this thread back I didnt read it all but maybe there may be a need for bearing number for replacement.. its SKF 331274
    I am also working on a NTN equivalent.

    Need to replace a 93 612 LC4 set.