Loctite or No Loctite

[itznuthin]

I'm halfway through my Denali installation, and now I'm starting to put my bike back together. I'm so new to this that I don't even know the basics, so I need the help of some experienced people. How often should I use Loctite when I reinstall bolts and screws (I'm only using the blue medium Loctite).

Examples:
* larger T40 bolts attaching the seat holder to the frame, these bolts point downwards so do I still need Loctite if I properly torque them, there is no apparent evidence of anything having been applied to the bolt when I removed it, but I suspect BMW may use something that doesn't have a distinct color like Loctite

* small body part screws that usually are horizontal, I assume these should never get Loctite since they go into those light receptacles

My default at this point, pending your input is as follows:

* any small frame bolt/screw that is used to attach the plastic panels to the bike should never get Loctite.

* all other bolt, whether they point up, down, or sideways, regardless of size (T15 through T50), should have medium Loctite applied.

I also tend to put a pretty good amount of Loctite on the bolt (for example, on the Denali bolts I've installed for the light mount, horn, etc.). Do I need to be careful about the amount I use?

Your advice is greatly appreciated. Regards, Don

 

[20774]

Be careful of the torque applied, depending on the instructions. If something is to be installed dry, as in no Loctite, then you need to back off the applied torque because the Loctite will create more sliding friction and you can easily over torque the bolt/fastener. I would think the instructions should be clear on the use of Loctite. If not, and the supplier can't help, maybe just go with the listed torque and check the fasteners every so often.

 

[pglaves]

Based on what you wrote I think you are using thread locker a lot of places it isn't needed. Very few fasteners need thread locker. Most have the simple job of keeping themselves in place. If you do use the stuff, use it sparingly. A drop or two is usually sufficient.

 

[Omega Man]

Based on what you wrote I think you are using thread locker a lot of places it isn't needed. Very few fasteners need thread locker. Most have the simple job of keeping themselves in place. If you do use the stuff, use it sparingly. A drop or two is usually sufficient.

I'm with Paul.

That said, if I thought something may "wander loose" I will put a bit of RTV silicone sealer on it. It "gums up" the threads just enough to not let things fall off. In a pinch, I have used a piece of black electrical tape (3-M 33+) on the threads and let the nut be cranked through the threads enough to provide an easy bind that works yet easy to undo.

OM

 

[skibum69]

Depends what you're riding, my KTM 640 Adventure needs loctite on pretty much everything.

 

[51797]

Blue and purple loctite are service removable, meaning that the bolts/screws can be removed with just normal hand tools, Red loctite is intended for PERMANENT installation and needs to be heated to smoking hot to release. Stay away from it except in critical situations. Proper torque on just about any fastener will keep it in place in the majority of instances.

Frank

 

[lkraus]

The only threads that I use loctite on are the ones that BMW used a thread locker on. BMW does not use invisible thread locker. You can see the remains of the blue thread locker when you remove the bolt or screw. If you have the factory service manual, these are usually considered one-time-use bolts, which come with a dry, blue, coating on the threads. These are not bolts that are likely to have been stretched in use, and I can't see replacing a bolt simply to have fresh thread locker, so the threads get cleaned up with a small wire brush and drop or two of blue Loctite applied. You only need enough to coat the threads that will be engaged.

The only loose nut on my bike is sitting in the seat.

 

[gregu]

I found a torque sheet on the BMW Adv site that was pretty good. I cross referenced a few of the torque values and they match. Therefore, I am assuming that the dry, loctite, never-sieze annotations are correct. Also assuming this thread is about shifthead motors. (I hope the pdf attaches and can be viewed)

 

[classicvw]

I'm with OM and Larry. Not on everything. If BMW used it, I'll use it.
I'll definitely use it on accessories that I may add like Denali lights, or a handlebar mount for something like a GPS, or added rear lights, etc where torque values are unknown and I have to install it by "feel".

 

[itznuthin]

I used Loctite based on the size of the bolt - couldn't see Loctite residue

Thanks for the information. I probably would have used Loctite on way too many things and wound up in trouble at some point in the future. As suggested in the responses, I decided to use Loctite only where I saw evidence of it being used previously by looking at the bolts I had removed. It was only when I received the replacement for the bolt I stripped that I realized I couldn't see Loctite residue on the bolts.

For example, in looking at the larger bolts I had removed for the section that holds the rear seat and pannier racks, it didn't look to me like there was any Loctite, so I planned to simply torque the bolts and not put anything on them. However, when I received the BMW replacement for the bolt where I had stripped the Torx head, blue Loctite was clearly applied to them, so I used Loctite for all the larger bolts when I reinserted them.

I had expected to see clear evidence of blue residue on the bolts I removed, but I didn't. However, on looking more closely I should have noticed what appeared to me to be a bit of grime/dirt. I assume this was the residue of Loctite that no longer retained its original blue color.

Another learning experience.