J b weld Head Bolts

GoldenMotor.com

2door

Moderator
Staff member
Sep 15, 2008
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Re: J b weld

Don't do it. You're gonna hear opposing view points but you asked for advice and that's mine. Do it right the first time, and you won't have to do it again.
Retap to the next larger size then do not overtighten the studs/nuts and you'll be good.
Glue has a place but it isn't here
Tom
 

DuctTapedGoat

Active Member
Dec 20, 2010
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Re: J b weld

JB Weld is removed with heat - for this reason I would say that the application does not suit JB Weld.

Goat Herder is right - get a Helicoil kit. HF has them all the time.
 

biknut

Well-Known Member
Sep 28, 2010
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Dallas
Re: J b weld

Helicoil is the correct repair. A helicoil repaired thread will be stronger than the original. Another plus is they're not hard to install.
 

DuctTapedGoat

Active Member
Dec 20, 2010
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Re: J b weld

Now, I saw this at a local auto shop - it's a spark plug repair kit. Repairs stripped out spark plug holes. Might be something to look into.
 

DaveC

Member
Jul 14, 2010
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Boise, ID
I think, I'm not sure but I seem to remember sets of helicoils or threaded inserts with taps at Harbor Freight. I know I've seen them at McMaster-Carr.
 

Goat Herder

Gutter Rider
Apr 28, 2008
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I think, I'm not sure but I seem to remember sets of helicoils or threaded inserts with taps at Harbor Freight. I know I've seen them at McMaster-Carr.
DaveC said:
What's going on is the Chinese don't tap the holes to the bottom. Then there is less of the threads engaged to prevent pull-out. Also the acorn nut bottoms out and the stud starts to thread into the block and it can't due to the hole not being tapped so the stud doesn't thread, it just pulls out.

Threading the stud holes is one of the things on the "what to do before you install your motor" thread. One of the first pieces of advice is get rid of the acorn nuts and use real ones from a hardware store or a nut and bolt place.
This was a interesting point I wounder how many of these motors might just simply need taped out deeper before the damage is done.
 

Chrisflik

New Member
Apr 2, 2011
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California
I wouldn't helicoil or retap and go to a bigger bolt. Your nor gonna be left with enough metal on the crank case to helicoil. If you go a bigger bolt its not gonna go through the "jug".
You can use a paper clip. Bend it stright. Put it in the jacked up hole. Bend it so it's 90 deg's. And now is the tricky part. You rescrew in the head bolt. The paper clip is gonna move around and all that but you'll figure it out. That clip is actually gonna be filling in the void of the jacked up thread. Basically the same concept as a helicoil but with out the surgery.
Now bolt your motor up. Get on your bike and ride. Simple...
Oh I forgot. After you bolt your motor up. Get on your computer and order another bottom end. You should find one for a 100$ shipped.
And I'll tell you like a tell all my customers or friends. I give you a 5 mile or 5 minutes. Witchever comes first warranty.
And don't let "Newbie" fool you. I'm claiming right here and now I got the fastest bike in L.A.
 

BarelyAWake

New Member
Jul 21, 2009
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Maine
Both the case and the cylinder have enough material to go one size over, which other than finding oversized head bolts ("all thread" is fine and commonly available) it's by far the easiest and most secure repair.

The thing with helicoils is although they're a bit of a pain, they allow you to retain the same sized fasteners, which can be handy.
 

Chrisflik

New Member
Apr 2, 2011
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California
Don't waste your time. Or do? I like to do things because "I'm not supposed to". Because I think "I know better". I do it all the time.
Check it out. Helicoil your case like dude says. You'll find out I'm right. And you'll be wishing you would have done like I advised you.
Order another case. Mess with your motor to try and make it work. Maybe you get it on the road till you get another bottom end. And if it keeps going, consider yourself lucky. Give yourself a pat on the back and count the days till it eventually will break. These motors are disposable. It breaks. You buy a new one. It's cheap China Aluminium. It's designed to break. If it were made in America it would still break. It's a bicycle. Motor? Bicycle with a motor. Whatever...
All I know. Is that I've put Thousands of miles on my putt-putt on L.A. streets. And untill someone is doing what I'm doing. Rolling how I'm rolling. They don't know what there talking about. From there cushy little suburban complexes with fresh paved roads. Like Monday morning quarterbacks. A lot of people on the Internet think they know it all.
Just like me.
On second thought. Dis-regard everything I just wrote.
I'm just another jerk on the internet...
Flik One!
 

Goat Herder

Gutter Rider
Apr 28, 2008
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I have helicoiled these engines ''successfully''. It like all things depends on who is doing it and their understanding of metallurgy drill bits and tape and die sets. Some stuff takes patients and due diligence of details. As a automotive mechanic I have been stuck with some intense surgeries on machinery. A said helicoil done right is much stronger than the original aluminum ever was!
 

retromike3

New Member
Jan 9, 2009
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Beaverton OR
Hard not to agree with Goat Herder. A helicoil will only work if installed correctly. Might as well give it a try. If all else fails your at least learning something. For me I had what a thought was a bolt strip, So I took the engine apart only to find out that the nut had failed not the bolt (sheepish grin) got the whole thing put back together only to have the motor mounts brake(sigh).

As long as you have the engine apart you might think of upgrading your hardware. Sick Bike Parts has a good kit for just that purpose.

good luck, Mike Owner Frye Bikes
 

MarkSumpter

New Member
Nov 27, 2010
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Ohio
Hey DaveC the thread repair kits similar to HeliCoils from HF are not worth the time to try to use and you also risk worbeling out a stripped hole so large it cannot be re-repaired. I only use the original HeliCoil brand made by Emhart Teknologies... Sure you pay a little more but in the end it is well worth the money.
 

rohmell

Active Member
Jun 2, 2010
1,531
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New York
If the threads stripped due to soft aluminum using a regular bolt, why would anyone think that the HeliCoils will hold any better in the same soft aluminum?