Frame problem, help required.

[Sander23]

I have a problem with the threads if the frame where the motor is mounted.
My frame is a hardtail frame from haibike.

Some time ago I got a second battery installed by the shop where I bought my bike. All good and well until I installed some wired lights to My bosch where I had to drop the motor to place the cables. Now I have some play on the motor wobbling left and right. If I pull left and right of the crankarm I can just see those screws move

Now I noticed 2 of the upper threads where the motor is mounted onto the frame where damaged.

1 I could just push the screw in without resistance of the thread, second had some tread left but when I wanted to give it the torque it needed it just keeps on spinning.

Now how can I restore both of those threads? What's the best way?

 

[thebarber]

Helicoil kit

M8 x 1.25mm Thread Tap Repair Cutter kit helicoil 15pc set damaged thread AN063 5056133309461 | eBay

M8 x 1.25 thread insert. - 1 x drill bit. - 19 x 10.8mm thread length inserts. -Creates a stronger internal thread in soft materials. - 1 x insert installation.

www.ebay.co.uk

 

[Sander23]

Is that helicoil strong enough for motor mounts?

 

[RustyIron]

Barber is right, a Helicoil is the best solution to the problem.

And I'll say this again, although few listen. Aluminum has a tendency to gall. Stainless has a tendency to gall.

You're keenly aware of this because the threads have pulled out of your frame. Proper assembly requires cleaning of both threads so there is no contamination. Apply a thin layer of anti-seize. Assemble and torque to proper specifications.

Anti-seize will allow more accurate torque readings and your fasteners will be less likely to gall under assembly or disassembly.

Some might suggest Loctite. It helps, but it's suboptimum.
Some suggest grease. That's bush league. Use the right product for the job.
Some assemble things dry. They're wrong.
And some don't clean their fasteners before assembly. My words for them are impolite.

Did the shop that worked on your bike last go through all the extra trouble to make assemble things properly? It's hard to know for sure. But the threads are jacked, that's for certain. There's only one way to know for sure that your bike gets the attention you expect. Do it yourself.

 

[thebarber]

If fitted correctly and locking compound used.
If there's room on the back you could bodge a nut in, but that's not the best way.
Try a frame builder

 

[Sander23]

Barber is right, a Helicoil is the best solution to the problem.

And I'll say this again, although few listen. Aluminum has a tendency to gall. Stainless has a tendency to gall.

You're keenly aware of this because the threads have pulled out of your frame. Proper assembly requires cleaning of both threads so there is no contamination. Apply a thin layer of anti-seize. Assemble and torque to proper specifications.

Anti-seize will allow more accurate torque readings and your fasteners will be less likely to gall under assembly or disassembly.

Some might suggest Loctite. It helps, but it's suboptimum.
Some suggest grease. That's bush league. Use the right product for the job.
Some assemble things dry. They're wrong.
And some don't clean their fasteners before assembly. My words for them are impolite.

Did the shop that worked on your bike last go through all the extra trouble to make assemble things properly? It's hard to know for sure. But the threads are jacked, that's for certain. There's only one way to know for sure that your bike gets the attention you expect. Do it yourself.

View attachment 81066

The shop Certainly did not do it the right way. It even lost its haibike dealership. I would certainly never go back there again. I do the maintenance myself lately.

So I need to drill the hole out, tap a new thread for the helicoil and when putting in the helicoil apply some nickel anti seize lubricant.

Won't the helicoil keep spinning when putting it in?

 

[RustyIron]

So I need to drill the hole out, tap a new thread for the helicoil and when putting in the helicoil apply some nickel anti seize lubricant.

Use the anti-seize on the threads of the fastener that mounts your motor. For the Helicoil, install it EXACTLY as indicated in the instructions. The Helicoil relies on friction to stay in place. It's a one-time installation that will not need to be removed.

Try not to be tempted by cheap "thread repair kits" that come from that country that is renowned for cranking out trashy products. Get a genuine Helicoil kit.

 

[Sander23]

HBM M 5 - M 12 Schroefdraad Reparatieset

Bevat alle benodigdheden ter reparatie van beschadigd schroefdraad. Boor het gat op met de meegeleverde boor. Tap nieuw schroefdraad in het gat. Monteer een schroefdraadhuls met montagehulpstuk. In de schroefdraadhuls past nu weer de originele bout. Wordt ook gebruikt ter versterking van...

www.hbm-machines.com

Something like this? Order does thuis look like a cheap kit

 

[Doug Stampfer]

I'd suggest that you only get one go with the helicoil & given the consequences if done incorrectly I'd recommend getting an engineering shop to do it. It'd cost bugger all to do.

 

[Sander23]

I'd suggest that you only get one go with the helicoil & given the consequences if done incorrectly I'd recommend getting an engineering shop to do it. It'd cost bugger all to do.

It's not something I would experiment on my bike with. I would definitely practice it first on other piece of aluminum

 

[Sander23]

Barber is right, a Helicoil is the best solution to the problem.

And I'll say this again, although few listen. Aluminum has a tendency to gall. Stainless has a tendency to gall.

You're keenly aware of this because the threads have pulled out of your frame. Proper assembly requires cleaning of both threads so there is no contamination. Apply a thin layer of anti-seize. Assemble and torque to proper specifications.

Anti-seize will allow more accurate torque readings and your fasteners will be less likely to gall under assembly or disassembly.

Some might suggest Loctite. It helps, but it's suboptimum.
Some suggest grease. That's bush league. Use the right product for the job.
Some assemble things dry. They're wrong.
And some don't clean their fasteners before assembly. My words for them are impolite.

Did the shop that worked on your bike last go through all the extra trouble to make assemble things properly? It's hard to know for sure. But the threads are jacked, that's for certain. There's only one way to know for sure that your bike gets the attention you expect. Do it yourself.

View attachment 81066

Disassembled the motor today for further inspection and saw the threads on where also in bad condition. Can I do the same there?

And this nickel anti seize isn't that the same as other good montage grease?

 

[RustyIron]

Disassembled the motor today for further inspection and saw the threads on where also in bad condition. Can I do the same there?

And this nickel anti seize isn't that the same as other good montage grease?

Anti-seize is not grease. Grease is not anti-seize.

 

[Howz]

Helicoil kit

M8 x 1.25mm Thread Tap Repair Cutter kit helicoil 15pc set damaged thread AN063 5056133309461 | eBay

M8 x 1.25 thread insert. - 1 x drill bit. - 19 x 10.8mm thread length inserts. -Creates a stronger internal thread in soft materials. - 1 x insert installation.

www.ebay.co.uk

I’ve used one of these kits on my BMW GSA, I had no prior experience or knowledge of using helicoils, it worked well, the helicoil won’t keep spinning, I would as others have said have a practice first though…..or just take it all to an engineering place and get them to do it.

 

[Sander23]

Anti-seize is not grease. Grease is not anti-seize.

My bad I meant something like this,

ASC-1 Anti-Seize Compound

Reduces friction and protects against corrosion in threaded and press fit applications.

www.parktool.com

 

[Hardtail]

A note on tapping a blind hole like that.

You usually need to use a bottoming tap after the initial standard (tappered) tap to get the thread cut to the full depth.

Don't worry, a helicoil repair is stronger than an original thread cut in to the aluminium.

 

[surfermann]

Also, for sure with stainless, and maybe aluminum as well: When turning nuts and bolts, turn slowly. Turning fast can create micro-heating which is hot enough to melt and weld stainless. Also called a cold weld. If this occurs the part is trashed.

 

[Sander23]

Fixed all the threads today with those helicoil. Did it first time and straight away on the bike and bosch motor and works great.

Brilliant solution!