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  1. #1
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    Crush tube purpose?

    I'm just curious what does that crush tube do anyway? It's between the bearings on the pivot bolts (I think just on the older) VPP linkage.

    When I replaced my bearings, I couldn't really see a reason for it, but I kept it in there.

    I was just reading a thread from 2010 where someone said leaving the crush tube out solved his problem with worn bearings and loose linkage. I can't see any purpose for the crush tube, nor can I see how leaving it out would effect bearing life in any way. Help me to understand please!

  2. #2
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    I can't tell you why, but when I replaced my bearings on my TVP i called Intense and they told me not to use it with the new bearings I ordered. My riding buddy has that bike now and it's been going strong for over a year now with no bearing issues.

  3. #3
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    Thanks. Now I'm more confused.

  4. #4
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    Ok I found an old thread, that leads me to believe the crush tubes help support the cartirdge bearings from lateral (thrust) loads.

    When the design switched to angular contact bearings, the side support was no longer needed. The tubes were kept in for a while to help direct grease from the grease ports, but I guess they figured that wasn't necessary.

    Trojans1993, do you have a newer bike with the zerk ports? If you do, they probably told you to leave the crush tube out simply because it isn't needed. If you have an older bike without the ports, I'm wondering if they might have given you angular contact bearings to replace the old full compliment bearings.

  5. #5
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    Here's the old thread:

    no more crush tubes in new frames

    I can now see why some would think removing the tube helps with loose pivot bolts. If the crush tube is too long, it would interfere with seating the bearings.

  6. #6
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    Yes, I believe my TVP had the zerk ports and was from a run when they just stopped using the crush tubes. My LBS (not yet aware of the change) wanted to put a crush tube in there and I think I read that same thread so I called Intense myself to confirm that it was not needed on my TVP.

    Earlier runs of the TVP may still require them so I wouldn't want you to ditch it just yet. Just call (not email) Intense on their (951) area code phone number and they should be able tell you for your specific frame if it is still needed or not - it may depend on the build date of your VP. Good luck, hope you get it back on the trail soon.

  7. #7
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    Hello all, crush tubes are not to be used with the Angular Contact Bearings. The ACB's adjust similar to a headset, and is tightened until the side to side play is gone. We have found this to be about 150 inch pounds, and I usually go just beyond a little drag, since bearings usually settle in. A follow up inspection after a ride or two to insure no slop.

    Crush tubes are used between standard cartridge bearings to prevent the excessive side loading of that particular bearing, usually only in NON-zirked frames, such as the Spider fro, Spider XVP, 5.5, 6.6, Uzzi VPX, Socom, and the original Slopestyle.

    Please feel free to call or email with any questions about any of our bearing systems, johnny@intensecycles.com and 951-296-9596.

  8. #8
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    Thanks for the info johnny. I'm not having any problems with standard cartridge bearings and crush tube set up, (other than occasional loosening), but I'm just curious if I could use ACB's next time I change them?

  9. #9
    Ole
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    If you put ACB in a frame not made for it, you'll have a hll of a time replacing them when that time comes. The ABC bearings require you to press/pound on the outer race to get the bearing out, the inner race will just fall out if you put any pressure on it.

    What you need to do is use a Dremel and make two notches in the shoulder the bearing stops against. Then you can later insert a punch from the other side of the frame, and stick it in the notch to pound out the outer race. This is how the ACB frames are designed.

  10. #10
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    Quote Originally Posted by Ole View Post
    If you put ACB in a frame not made for it, you'll have a hll of a time replacing them when that time comes. The ABC bearings require you to press/pound on the outer race to get the bearing out, the inner race will just fall out if you put any pressure on it.

    What you need to do is use a Dremel and make two notches in the shoulder the bearing stops against. Then you can later insert a punch from the other side of the frame, and stick it in the notch to pound out the outer race. This is how the ACB frames are designed.
    Thanks for that. Sounds like its not worth the trouble. Like I said, I'm not having any issues with my standard cartridges.

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