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Jrfitzny
| Posted on Saturday, August 04, 2012 - 05:39 pm: |
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Good afternoon, Somehow the top bolt of my caliper loosened itself, and while it was rubbing itself against my the rotor, it damaged a few of the internal threads on the frame. I don't have a tap and die set, especially not a metric set. Is this something a Harley dealer would have? This is a M8 sized bolt. Thanks, Fitz |
Cycledoc59
| Posted on Saturday, August 04, 2012 - 07:25 pm: |
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Get another M8 bolt, taper the tip slightly, then cut an in-line grove across the first few threads with a triangle file to the base of the threads. The taper helps get the home-made thread restorer started, and the cut cleans out and straightens the threads. |
Jdugger
| Posted on Saturday, August 04, 2012 - 11:11 pm: |
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Rear or front? |
Stirz007
| Posted on Sunday, August 05, 2012 - 12:03 am: |
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You'll only need a tap if the threads aren't too wallered out (through hole - for a blind hole, you'll need a bottoming tap). The tap will set you back ten bucks and can be found at most industrial supply type places. I'm not sure whether this would be something I'd trust to a helicoil, timesert or thread repair - never had the opportunity to make that decision. And no, I'd not bother with the stealership..... good luck (Message edited by stirz007 on August 05, 2012) |
Torquehd
| Posted on Sunday, August 05, 2012 - 12:57 am: |
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"I'm not sure whether this would be something I'd trust to a helicoil..." I trust steel threads more than aluminum threads (yes i realize a helicoil is still threaded into aluminum, but there's more surface area, which means more strength). I've helicoiled brake rotor boltholes and sparkplug holes and they worked just fine. if the threads are "wallered" out, you either need a helicoil or a new swingarm (since you said "frame" and not "caliper", i assume you're talking about the rear). |
Sprintst
| Posted on Sunday, August 05, 2012 - 08:39 am: |
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Yes, I hate aluminum threads. Just waiting to strip. Yes, helicoils are a great solution never heard of "wallered" lol |
Reepicheep
| Posted on Sunday, August 05, 2012 - 11:36 am: |
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quote:Get another M8 bolt, taper the tip slightly, then cut an in-line grove across the first few threads with a triangle file to the base of the threads. The taper helps get the home-made thread restorer started, and the cut cleans out and straightens the threads.
Nice tip Cycledoc, thanks! I have taps in most sizes, but not thread chasers. This sounds like a nice thing to try when I have an extra bolt laying around, and need to just chase a hole without removing material (like the tap would do). Thinking about it, instead of a triangle file, I might just cut a nice groove down the length of the bolt with a dremel tool cutting wheel. (Message edited by reepicheep on August 05, 2012) |
Stirz007
| Posted on Sunday, August 05, 2012 - 01:33 pm: |
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"I've helicoiled brake rotor boltholes and sparkplug holes and they worked just fine." Me too. But without photos or seeing it myself, I'm not prone to make that recommendation for a failure-critical part.
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Jdugger
| Posted on Sunday, August 05, 2012 - 02:47 pm: |
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Use a time-sert. They are often better than the original threads. |
1125rcya
| Posted on Sunday, August 05, 2012 - 04:23 pm: |
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You might as well pick up a metric tap/die set from your local auto store. If you take off your stock exhaust for any reason, you'll find that a tap will be needed to put the original bolts back in. |
Dannybuell
| Posted on Sunday, August 05, 2012 - 05:55 pm: |
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don't forget the anti-seize, especially with aluminum. |
Sir_wadsalot
| Posted on Sunday, August 05, 2012 - 11:21 pm: |
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Ditto on the tap & die set. A tap of the same size will do the same as the bolt, pretty much just stand the threads back up. It's something you need anyhow, 'specially if she's wallered out. (Wallered is hillbilly for wallowed) Either way, lube it up good, hand torque it slowly a quarter of a turn or so, back it off, turn it in again, go slow so you don't bully the threads worse. If you're cutting, automatic trans fluid is great, but WD40 should be fine for what you're doing. Remember, you're just moving the threads that are there, not trying to cut anything. |
Rodrob
| Posted on Monday, August 06, 2012 - 12:50 pm: |
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Caliper bolts are 5/8 SAE not metric. Don't know why they did that. 8mms are really close and will go in, but will eventually screw (no pun intended) things up. I used a special thread insert tool on mine. Can,t remember the name. I'll send a pic. It's expensive. We could work out a loan if you want. |
Nuts4mc
| Posted on Monday, August 06, 2012 - 01:19 pm: |
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8mm is closer to 5/16 than 5/8 (??) "keen-serts" are locking thread inserts (use them on heads to repair stripped spark plugs threads...otherwise the heli-coil comes out with the spark plug=not good) McMaster Carr has them: http://www.mcmaster.com/#key-locking-threaded-inse rts/=iqe8ed yes they are costly |
Rodrob
| Posted on Monday, August 06, 2012 - 02:02 pm: |
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5/16 - absolutely correct. My bad. Need coffee. Please send. |
Rodrob
| Posted on Monday, August 06, 2012 - 04:48 pm: |
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Pics of the thread insert tool I used.
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Jrfitzny
| Posted on Monday, August 06, 2012 - 07:25 pm: |
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Thanks for the replies. This is for the rear caliper. I'll try to make a thread chaser, and if that doesn't work I'll get a tap from harbor freight. Rob, I may take you up on your offer if the tap doesn't work, since it looks as though the time-sert requires boring out the hole. Thanks for pointing out that the bolt is 5/16", I'm not sure why they decided to mix/match standard and metric bolts either. (Message edited by jrfitzny on August 06, 2012) |
Rodrob
| Posted on Monday, August 06, 2012 - 07:38 pm: |
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Rear caliper might be metric. Double check. I just assumed it was the front, as that is a very common front caliper problem. Assume makes an ass out of u and me. |
Stirz007
| Posted on Monday, August 06, 2012 - 08:50 pm: |
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For my '08, rear(s) are metric, front(s) are SAE if that helps... (I was just worried there might be some crackage or something before I'd say you should go for it and you'd be fine - I'm paranoid that way....). |
Jdugger
| Posted on Monday, August 06, 2012 - 10:50 pm: |
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Rear caliper bolts are M8! |
Torquehd
| Posted on Monday, August 06, 2012 - 11:14 pm: |
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Taps do not "stand threads back up". Once thread material has been removed, it's gone. You can't make the aluminum re-appear. The only practical way to put threads back in that same spot is with a helicoil or timesert. you do, however, need a good tap and die set if you do your own work at all. |
Brumbear
| Posted on Tuesday, August 07, 2012 - 07:19 am: |
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Run a tap through it bolt it back up if it won't tighten get a longer bolt run it in put a nut and a star washer on the outside. |
Jdugger
| Posted on Tuesday, August 07, 2012 - 09:05 am: |
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> Taps do not "stand threads back up" Ignoring forming taps, of course http://www.practicalmachinist.com/vb/general-archi ve/how-thread-forming-tap-used-86164/ The whole problem with Aluminum in general, especially the cheap cast material the 1125r swing arm is made from, is it's only good for "one bend" or so. Chasing the threads to repair with a forming or cutting tap just serves to further weaken them, really. The correct answer is a thread insert such as the time-serts pictured. I did mine eons ago, and haven't had an issue since. Durable, steel threads. |
Mako
| Posted on Wednesday, August 08, 2012 - 11:01 am: |
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check out groove pin thread inserts. |
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