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  1. #1
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    Broken main pivot bolt

    Uggh, Was on a Utah trip and broke my main pivot bolt on the first day of riding. No Titus dealers anywhere near St. George so a local shop set me up with a nice Cannondale rental for the rest of the trip.

    I can't believe the pivot bolt would shear off at the threads like that after less than two years of use. One of my riding buddies is a mechanical engineer and he looked at the hollow aluminum pivot bolt and just shook his head and said it should never have been made out of aluminum. Does anyone know if I can get a steel or Ti one or has Titus changed the design of the bolt? I hope the threads aren't damaged in the swingarm. This is probably a good time to replace all the bearings and bushings as well.

    Has anyone else had their pivot bolt shear off?

  2. #2
    "El Whatever"
    Reputation: Warp's Avatar
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    Your friend's engineering analysis doesn't explain how mine which is identical has survived for 4yrs plus.

    AFAIK, the design changed for the Light Rail system (or that looks to me). Other than that, the main pivot bolt is the same since 2004, I believe.

    Geo or Demo Slug, please correct me if wrong, but the steel bolt was used only on the SuMo.

    There had been cases of broken bolts, no doubt. But I wouldn't call it a weak point. Commonly, the seatstays on a Motolite or the headtube on a Switchblade would give up first.
    Check my Site

  3. #3
    what's that rattle?
    Reputation: Blofeld's Avatar
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    Ouch! That's a terrible thing to have happen on a road trip!

    I know mine loosens up quite frequently (despite using LocTite and a torque wrench) and it's annoying to have to take off the cranks to tighten it up. It often makes me wonder if the extra play is making things wear out any faster...

    Personally, I'd give Al another try before investing in a (custom?) Ti or steel bolt.

  4. #4
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    Quote Originally Posted by Blofeld
    Ouch! That's a terrible thing to have happen on a road trip!

    I know mine loosens up quite frequently (despite using LocTite and a torque wrench) and it's annoying to have to take off the cranks to tighten it up. It often makes me wonder if the extra play is making things wear out any faster...

    Personally, I'd give Al another try before investing in a (custom?) Ti or steel bolt.
    Ya, I won't bother with a custom bolt, but was wondering if Titus had changed design or offered a steel one. Haven't had any trouble with mine backing out. I removed it about a year ago to check the bearings and torqued it to spec. Can't recall if I used loctite or grease on the threads.

  5. #5
    Hueston Woods Trail Crew
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    I can send you a new bolt if you need one.
    Email me your address again.
    bob@bikerbob.com

  6. #6
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    Quote Originally Posted by Bikerbob.com
    I can send you a new bolt if you need one.
    Email me your address again.
    bob@bikerbob.com
    Thank you for the kind offer, but I just dropped the bike off at my local shop as I think a professional should work on removing the broken threaded piece that is stuck in the rear triangle threads. I do not have any experience in doing that. I also wanted to have them replace the bearings.

  7. #7
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    Bob's a sport. Bummer on the problem showing up on your trip. The aluminum bolt is not highly stressed. The load is in sheer. I figure that the ball bearings froze, subjecting the bolt to twisting stresses. This fatigued the pivot bolt. My ML needs all the ball bearings in the suspension replaced at least once a year (most are frozen solid). I live in NW Florida, we have our share of mud, clear water crossings and sand. Buy the ball bearings from Enduro, they are cheap. James

  8. #8
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    Quote Originally Posted by OldMTBfreak
    Bob's a sport. Bummer on the problem showing up on your trip. The aluminum bolt is not highly stressed. The load is in sheer. I figure that the ball bearings froze, subjecting the bolt to twisting stresses. This fatigued the pivot bolt. My ML needs all the ball bearings in the suspension replaced at least once a year (most are frozen solid). I live in NW Florida, we have our share of mud, clear water crossings and sand. Buy the ball bearings from Enduro, they are cheap. James
    You could be correct about the bearings as on the pivot bolt near where it sheared off there were some iron oxide stains. There were no stains on the other side of the bolt (head side) However, the outside bearings seemed to move ok, but couldn't really tell about the inside one.

  9. #9
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    EJ 92606....... Just to be on the safe side I would recommend replacing both bolts. Even though the other bolt hasn't failed their is a good chance it was over stressed during the sheering incident.

    Sopwithcamel

  10. #10
    Spring! Spring! Spring!
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    i've had one main pivot bolt break on my Quasi since I've had it (June '03). Tons and tons of miles, and the break happend when I fell on top the bike, with the bike laid out sideways in such a way that rocks were supporting the front & back of the frame.

    Of course, this was like the 5th or 6th time that i've ended up in such an ungainly situation.

    I keep a spare in my kit, as I do of the bearing set, just in case. Just had to replace the horst link bushings this past weekend as a matter of fact. Second set since '03.

  11. #11
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    Quote Originally Posted by sopwithcamel
    EJ 92606....... Just to be on the safe side I would recommend replacing both bolts. Even though the other bolt hasn't failed their is a good chance it was over stressed during the sheering incident.

    Sopwithcamel
    Are you talking about the 2 pivot bolts on the rocker? Not a bad idea.

  12. #12
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    Quote Originally Posted by bear
    i've had one main pivot bolt break on my Quasi since I've had it (June '03). Tons and tons of miles, and the break happend when I fell on top the bike, with the bike laid out sideways in such a way that rocks were supporting the front & back of the frame.

    Of course, this was like the 5th or 6th time that i've ended up in such an ungainly situation.

    I keep a spare in my kit, as I do of the bearing set, just in case. Just had to replace the horst link bushings this past weekend as a matter of fact. Second set since '03.
    Thanks for the info. How do you know when the horst link bushings are shot? I asked my dealer to replace all the bushings and bearings and he said the Horst link ones are probably fine after 2 years...he said they don't wear much.

  13. #13
    Spring! Spring! Spring!
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    They don't wear much, you can probably get them to wear longer too with some kind of cleaning/lube regiment but they're so dead-bang easy to deal with i'm not sure why.

    How to tell if they're worn without inspection? I'd look for slop at the busing, or noise (mine were squeaking like a tired out bed in a Motel 6), or if they stay dirty/crappy. Probably wear faster in wetter environments. I live in Austin TX and thus with the dearth of moisture they don't see much wear-wet (although I have raced on them in the rain).

    You probably want to watch yours more closely, because of the wear mine induced for my lack of cleaning them regularly enough they've slightly worn one side of the clevis joint and thus I have a small side-2-side gap on the drive-side horst pivot. Functionally fine and I think structurally it's okay to ride but I can't imagine that play there is a good thing in the long run. Of course, my chainstay is bent a little at the main pivot from me falling on it. :P

    I got my spare set through BikerBob, cool dude.

  14. #14
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    Quote Originally Posted by EJ_92606
    Has anyone else had their pivot bolt shear off?
    No not me... but, I broke my main shock bolt on my 2005 ML last October in Moab. At the time the bike had 4500 miles of hard riding. Luckily, there is a Titus dealer in town and my vacation was saved.

    Anyway, when I got home to AK I replaced all my bearings, bushings and all my bolts (excluding the swinglink bolts). Now I have extras...... and more importantly a peace of mind.

    Just replace everything..... for $100 you can't go wrong.

    Regards,

    EndUser
    My advice and $3 will buy you nothing more than a tunafish sandwich.

  15. #15
    what's that rattle?
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    Guapo Bolt?

    I was just comparing the bolt in my MotoLite to the one in my Guapa; the MotoLite's has less material under the threads where it exits the chainstay. I didn't feel like removing two cranksets to see if they're interchangeable, but other than the ID the two bolts look the same from the outside. Perhaps someone in the know can tell you if the parts are a) actually different, and b) interchangeable, but perhaps a Guapo bolt is the stronger part you're looking for...

  16. #16
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    Thanks, I took mine apart a year ago and cleaned/re-assembled. Probably due for another cleaning.

    Quote Originally Posted by bear
    They don't wear much, you can probably get them to wear longer too with some kind of cleaning/lube regiment but they're so dead-bang easy to deal with i'm not sure why.

    How to tell if they're worn without inspection? I'd look for slop at the busing, or noise (mine were squeaking like a tired out bed in a Motel 6), or if they stay dirty/crappy. Probably wear faster in wetter environments. I live in Austin TX and thus with the dearth of moisture they don't see much wear-wet (although I have raced on them in the rain).

    You probably want to watch yours more closely, because of the wear mine induced for my lack of cleaning them regularly enough they've slightly worn one side of the clevis joint and thus I have a small side-2-side gap on the drive-side horst pivot. Functionally fine and I think structurally it's okay to ride but I can't imagine that play there is a good thing in the long run. Of course, my chainstay is bent a little at the main pivot from me falling on it. :P

    I got my spare set through BikerBob, cool dude.

  17. #17
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    Thanks for all the tips, my local shop got the new bolt in after 2 days and pulled the broken bolt out of the threads easily. The tech said all the bearings were fine and there was no need to replace. Out the door for the $15 bolt and $10 labor...not bad! The tech said he had never seen the pivot bolt snap like that.

  18. #18
    on my 3rd wind...
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    My Intense Tracer had the same bolt shear at the main pivot near the thread. It was solid steel bolt that ran the entire length of the bb shell. It sheared after 4 years of use. I didn't realize anyone used main pivot bolt that is made out of aluminum and hollow. That main pivot near the bb takes some serious loading.
    sth

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