dr650 snapped clutch spring bolt at 7 ft lbs of torque.

Discussion in 'Thumpers' started by the.seeker, Jun 3, 2018.

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  1. the.seeker

    the.seeker Adventurer

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    So I had a bizarre incident today working on the DR650. I was on the tail end of performing the NSU fix when I was starting to put on the clutch plate springs. When I snapped the what I believe to be an M6 bold right off into the hub sleeve. I went into a panic. I was going to apply 7 ft lbs of torque as per the recommendations and it simply twisted out before I got close. I don't believe I over torqued it at all as I hadn't even finished compressing the spring. Also supporting my not overtorqued diagnosis, I was able to simply back it out by hand just using a drill bit and manually turning it with my fingers. No damage was done to any of the aluminum pieces. The bolt head simply twisted off before the spring even came close to being bottomed out. I pulled out the other bolts and saw another one was about ready to snap and had started to elongate. I'm completely dumbfounded because I know it was not under heavy pressure. I had another m6 bolt and out of curiosities sake I fastened it down with the same torque wrench on some scrap and it made it all the way to the click without an issue at all. Luckily the issue didn't do any real damage but it made me worry a bit. I have never heard of this happening before. It's a steel bolt. Sure it's small but 2 of the 4 failed on a very torquing. Is it possible it was getting some extra wear that I am unaware off?

    Here is an image of the problem bolts: https://imgur.com/a/NxHe029

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    #1
  2. galland1

    galland1 n00b

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    TLDR. Most don't have the correct tool for this. Dry bolt and dry threads?

    Sent from my SM-N950U using Tapatalk
    I have heard of this before more than once . Also the front fork pinch bolts. Very soft and easy to over torque.
    #2
  3. villageidiot

    villageidiot Long timer Supporter

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    You better have one small ass torque wrench to get an accurate 7lbs.

    I just “hand tight” the clutch bolts, they tighten til the bottom and that’s it. Snug.
    #3
  4. ER70S-2

    ER70S-2 Long timer

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    As mentioned, I won't use a torque wrench on 6mm fasteners unless it's made for low torque values. The problem with torque wrenches is their length, small wrenches are short for a reason.

    My 6mm torque wrench is a 5" ratchet.
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    Make sure you rotate those pawl teeth to the front before installing the cover.
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    #4
  5. the.seeker

    the.seeker Adventurer

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    Yeah but the thing is I didn't even bottom out on the spring. I didn't approach anywhere near 7lbs. That is what makes the whole thing weird. I was tightening them down evenly as you should. Once I twisted one head off I carefully took the other springs and had 3 more turns to bottom out.
    #5
  6. ER70S-2

    ER70S-2 Long timer

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    That it broke before contacting the tower is very weird. :scratch I'd order all 4 new bolts from Suzuki, someone may have done the damage before you (if you bought it used).
    #6
  7. the.seeker

    the.seeker Adventurer

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    True. Could have been that. It's not the end of the word since the bolt was easily backed out. Just perplexed is all that 2 bolts would fail like that.
    #7
  8. ER70S-2

    ER70S-2 Long timer

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    Some mysteries ... stay mysteries.
    #8