Author Topic: Stripped front axle holders?  (Read 2422 times)

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Offline jakec

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Stripped front axle holders?
« on: February 15, 2020, 11:44:17 PM »
I was putting my wheel back on my 550 after rebuilding the forks. I just needed new fork seals. So I go to tighten up the nuts, and I found that they hard to spin but they never stop spinning. I’m using a torque wrench set at 16 ft/lbs.

I’m confused because this was happening on at least 3/4 nuts. It was fine before so I don’t know how this would happen. I guess I’m just looking for alternative ideas before I take the lowers off (somehow keeping the tubes in? I JUST put the whole front end together, ugh).

I can’t say for sure but i might have been over torquing the nuts before. If they’re all stripped I guess I need an m10 helicoil kit and 4 studs?
1970 CB750 K0
1977 CB750 Chop
1984 Big Twin Evo Chop
1997 XR650L

Offline PeWe

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Re: Stripped front axle holders?
« Reply #1 on: February 16, 2020, 12:56:25 AM »
Only studs are bad,right? Honda sell those studs for the fork wheel axle caps.
Your torque wrench might be wrong. I always tighten these nut by feel and weak thread locker.
« Last Edit: February 16, 2020, 01:13:33 AM by PeWe »
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline jakec

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Re: Stripped front axle holders?
« Reply #2 on: February 16, 2020, 09:49:52 AM »
If the studs can spin wouldn’t that indicate that the threads in fork lowers are bad? I would think those threads would give out first.
1970 CB750 K0
1977 CB750 Chop
1984 Big Twin Evo Chop
1997 XR650L

Offline jgger

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Re: Stripped front axle holders?
« Reply #3 on: February 16, 2020, 09:59:27 AM »
True if the studs are either bottomed out or seated to the threaded shoulder.

JB makes a thread repair that works pretty good too. Or a timesert is stronger than helicoil, just sayin' there are other options.
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline jakec

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Re: Stripped front axle holders?
« Reply #4 on: February 16, 2020, 10:35:43 AM »
I will remove 1-2 studs today with the forks still on the bike and inspect the threads.
1970 CB750 K0
1977 CB750 Chop
1984 Big Twin Evo Chop
1997 XR650L

Offline rotortiller

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Re: Stripped front axle holders?
« Reply #5 on: February 16, 2020, 11:05:02 AM »
Use helicoils if the aluminum threads are buggered. The helicoils come in various depths which means you can have deep full stud steel on steel threads should you desire. It will, when done correctly be the strongest repair you can make. Most guys complain about helicoils failing because they do not know what they are doing. If you use a ten thread coil instead of a 5 thread coil it does not require rocket science to see the strength difference.   There is a coil count chart for aluminum to select helicoils that  will allow a specific grade bolt to snap before failing of the repair. If in doubt maximize the coil lenght  and "Bobs ur Uncle".You do need to make sure the stud is the part spinning though which I expect you have.  https://amesweb.info/Screws/helicoil-length-chart-calculator.aspx
« Last Edit: February 16, 2020, 11:55:15 AM by rotortiller »

Offline tlbranth

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Re: Stripped front axle holders?
« Reply #6 on: February 16, 2020, 04:28:34 PM »
a timesert is stronger than helicoil, just sayin' there are other options.

Do you know this for a fact or is it just your opinion. Not trying to be contrary. I've used helicoils but not timeserts. The helicoils worked fine for me.
Don't own a Vanagon
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1970 CB750 K0
1975 GL1000
1999 GL1500
2002 VT750-CDA ACE - Momma's bike
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Offline bryanj

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Re: Stripped front axle holders?
« Reply #7 on: February 16, 2020, 04:36:46 PM »
I have personaly used timeserts(or keensert) when helicoils have failed on cam tower studs but this was back in the 70's
Problem with them you need enough metal to safely take a 10mm thread plus they used to ised the "non standard" pitch of the ones available making taps a special order and expensive
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline jgger

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Re: Stripped front axle holders?
« Reply #8 on: February 16, 2020, 08:56:33 PM »
a timesert is stronger than helicoil, just sayin' there are other options.

Do you know this for a fact or is it just your opinion. Not trying to be contrary. I've used helicoils but not timeserts. The helicoils worked fine for me.

I know it is the only repair that will hold up for the infamous Ford spark plug blow out. I think that the time sert is better where the temps can get high, obviously not the fork legs.

As far as a pull test goes...........no I dont know for sure.
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline rotortiller

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Re: Stripped front axle holders?
« Reply #9 on: February 17, 2020, 05:48:18 AM »
Quote
helicoils have failed on cam tower studs but this was back in the 70's
Problem with them you need enough metal to safely take a 10mm thread

I believe they use 6mm thread and not 10mm. If you somehow retrofitted something that thick and the wall became that thin all bets are off with most repairs.

Offline bryanj

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Re: Stripped front axle holders?
« Reply #10 on: February 17, 2020, 07:04:30 AM »
Correct on the studs a 6mm inside thread timesert has a 10mm outside thread
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!

Offline jakec

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Re: Stripped front axle holders?
« Reply #11 on: February 21, 2020, 08:43:38 AM »
Ok so I finally was able to check last night and it is the front two studs, their threads are stripped. right around the middle of the exposed thread area (there the nut would be when tightening on the axle holder) but have bad threads.

One of them I was able to back off the nut, but when trying to use the 2-nut removal trick I was making the threads worse on both the stud and the nut. Going to purchase some new nuts and try again. I may be able to repair the threads on this one by running a nice new nut on it.

One of them I can't get the nut off,  it just spins in place on the stud, about halfway off. I have no idea what to do about this one. Any help?
1970 CB750 K0
1977 CB750 Chop
1984 Big Twin Evo Chop
1997 XR650L

Offline Don R

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Re: Stripped front axle holders?
« Reply #12 on: February 21, 2020, 09:08:15 AM »
 I haven't removed the fork studs on purpose but there are stud wrenches, they have a cam that grips the stud while you turn it out, usually with a ratchet.  If they have thread locker from the factory a little heat may be in order.
 I was having a hard time visualizing the stud with a nut turning in the fork leg.
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Offline jgger

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Re: Stripped front axle holders?
« Reply #13 on: February 21, 2020, 09:11:29 AM »
Put something under the nut to lightly wedge the nut toward the end of the stud. If the axle cap is on then wedge between it and the fork. Try turning the nut off to see if you can get purchase on the threads. It may come off hard, but you need to change the stud anyway.

The studs probably have thread locker so you need to use heat to remove.

Good luck
"The SOHC4 uses a computer located about 2-3 ft above the seat.  Those sometimes need additional programming." -stolen from  Two Tired

The difference between an ass kisser and brown noser is merely depth perception.  Stolen from RAFster122s

Offline jakec

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Re: Stripped front axle holders?
« Reply #14 on: February 21, 2020, 09:32:25 AM »
I thought about wedging something in between the holder and fork lower. Using heat to remove, are we talking heat gun heat or torch heat? I haven't taken the plunge on a torch yet.
1970 CB750 K0
1977 CB750 Chop
1984 Big Twin Evo Chop
1997 XR650L

Offline tlbranth

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Re: Stripped front axle holders?
« Reply #15 on: February 21, 2020, 09:48:40 AM »
Since the aluminum is good, I'd put visegrips on the stud, remove it and buy a new stud. The stud's a goner anyway.
Don't own a Vanagon
Don't work at Boeing
Life is good

1970 CB750 K0
1975 GL1000
1999 GL1500
2002 VT750-CDA ACE - Momma's bike
Terry

Offline jakec

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Re: Stripped front axle holders?
« Reply #16 on: February 21, 2020, 10:19:45 AM »
I did start on it with the vise grips but it was spinning & wrecking the threads so I stopped for the night.
1970 CB750 K0
1977 CB750 Chop
1984 Big Twin Evo Chop
1997 XR650L

Offline PeWe

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Re: Stripped front axle holders?
« Reply #17 on: February 21, 2020, 10:28:29 AM »
Most of the old CB 4s have same stud down the forks?
BOLT, STUD, 8X50mm
CB750 K6-76  970cc (Earlier 1005cc JMR Billet block on the shelf waiting for a comeback)
CB750 K2-75 Parts assembled to a stock K2

Updates of the CB750 K6 -1976
http://forums.sohc4.net/index.php/topic,180468.msg2092136.html#msg2092136
The billet block build thread
http://forums.sohc4.net/index.php/topic,49438.msg1863571.html#msg1863571
CB750 K2 -1975  build thread
http://forums.sohc4.net/index.php/topic,168243.msg1948381.html#msg1948381
K2 engine build thread. For a complete CB750 -75
http://forums.sohc4.net/index.php/topic,180088.msg2088008.html#msg2088008
Carb jetting, a long story Mikuni TMR32
http://forums.sohc4.net/index.php/topic,179479.msg2104967.html#msg2104967

Offline tlbranth

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Re: Stripped front axle holders?
« Reply #18 on: February 21, 2020, 10:55:33 AM »
I did start on it with the vise grips but it was spinning & wrecking the threads so I stopped for the night.

You have to really tighten the grips on. Use many hands to get the thing to click shut. Curved jaws would give more bite. Heating the area with a heat gun first might help. Don't fret the threads. If you think the stud might break off (that would be very bad), take the fork off, turn it upside down and form a plumber's putty dam around the stud. Put in some penetrating oil or atf/acetone mix and leave for a few days. Tap the end of the stud once in a while with a hammer. Then go at it with  the vise grips. Acetone might mess up a finish so be careful. Put the vise grips close to the fork.

Good luck.
Don't own a Vanagon
Don't work at Boeing
Life is good

1970 CB750 K0
1975 GL1000
1999 GL1500
2002 VT750-CDA ACE - Momma's bike
Terry