[Opus51569]

I've heard a number of people reference using Loc-tite for various applications. I understand what it does in principle, holding bolts in place that tend to work loose over time. I know there are different strengths of Loc-tite as well.

Beyond that, though, I'm curious if there are places on the bike that you find it particularly useful and in which strengths? Do you only use it for problems with loose bolts or do you use it as a "standard" part of assembly?

 

[Dinosaur]

I've used Loc-Tite blue for water bottle cage bolts and stems. That's about it. The blue strength is not so tight that you can remove the screw without too much difficulty. Screws for cleats might be another place. I have some in my garage, seldom use it anymore.

 

[shockfinder]

Every fastener gets either grease or lock-tite. I find I use lock-tite more on MTBs than my road bike. I use it on crank arm pinch bolts.

 

[Mel Erickson]

Blue is recommended for fasteners you want to stay tight but still be able to remove without difficulty. Use it for just about any bolt from stem to water bottle to brake to seatpost. For instance, lots of brake bolts come from the manufacturer with blue loctite already on the threads. Common in the mountain world for disc brake rotor and caliper bolts.

 

[Opus51569]

Thanks everyone. I've got a front brake that keeps wanting to drift off center after longer rides. I may have to give the blue Loc-tite a try.

 

[tom_h]

... For instance, lots of brake bolts come from the manufacturer with blue loctite already on the threads. ...

Those pre-applied "thread locking compounds" are a different formulation than Loctite thread adhesives. The former (see http://www.nylok.com ) can be re-used 5-10 times, primarily provide mechanical locking, and still work OK covered with grease.

Retail store Loctite is a chemical adhesive. Once the screww is removed and the bond is broken, need to clean the threads and reapply. Threads must be clean, no grease.

 

[DaveG]

always wondered about that

Those pre-applied "thread locking compounds" are a different formulation than Loctite thread adhesives. The former (see http://www.nylok.com ) can be re-used 5-10 times, primarily provide mechanical locking, and still work OK covered with grease.

Retail store Loctite is a chemical adhesive. Once the screww is removed and the bond is broken, need to clean the threads and reapply. Threads must be clean, no grease.

I always wondered about that blue stuff that comes on some bolts. Now I know. Thanks

 

[Kerry Irons]

Wrong answer

Thanks everyone. I've got a front brake that keeps wanting to drift off center after longer rides. I may have to give the blue Loc-tite a try.

It is highly unlikely that you need LocTite to keep your brakes properly positioned. First, your threads should be greased. Second, it is likely that you are not properly centering the brake in the first place. I've done an awful lot of brakes over the years and never had one that wouldn't stay in place when properly set up.

 

[MikeBiker]

When I raced off-road motorcycles, I had to Loctite almost all fasteners. I've never seen a need to use it on my road bicycles.

 

[tom_h]

Thanks everyone. I've got a front brake that keeps wanting to drift off center after longer rides. I may have to give the blue Loc-tite a try.

Most calipers come with thick, serrated washers intended to "bite" into the fork and caliper to keep them secure.

I did not want to do that on the bike I assembled, I just didn't like the idea of deep gouges in my fork.

I torque the front recessed bolt to about 70 ln-lbs , don't use the serrated washer, and the caliper is extremely stable and solid. Once in a while caliper seems slightly off-center ... on most dual pivot calipers there's a tiny adjust screw on one arm, that will recenter with high precision.

Before recentering caliper, ensure wheel is still true, and that hub is properly secured and centered in the fork's lugs/dropouts.

 

[mikemayf]

Need to be clear what type of bike/brake you're talking about. The replies seem to assume road bike with 'traditonal' caliper. If that is what you're asking about, make sure you are applying correct torque to the attachment bolt.

I also am not thrilled with the serrated washer that bites into the fork. However, it actually only 'bites' into the clear coat/paint, and does help keep the caliper from twisting. I use them, but flinch every time.

The other issue is the type of caliper and centering mechanism. If it is the type that simply swivels around the attachment bolt (e.g. SRAM and lower-end Shimano), adequate torque is important. If it is the type with a centering mechanism (e.g., a screw adjustment -- better Shimano), then if you correctly torqued the attachment 'bolt/nut' and it keeps moving, make sure the caliper isn't defective and centering mechanim is not locking in. If the centering screw is backed out significantly, dial it in a little more than half the range and manually center the caliper.

There should have been some 'loctite' on the attachment threads (generally 'whte' in color), and that should be more than adequate. If the threads were clean, I'd go with the blue but paying attention to the cautions others have given -- clean threads.

Good Luck.

 

[Opus51569]

I've done an awful lot of brakes over the years and never had one that wouldn't stay in place when properly set up.

Well, if you're ever in Iowa...

 

[Opus51569]

Every fastener gets either grease or lock-tite. I find I use lock-tite more on MTBs than my road bike. I use it on crank arm pinch bolts.

Pinch bolts have been an issue for me in the past as well, leading to a clicking in the drivetrain. I've tightened the bolts and had an LBS do it as well.

 

[Todd_Fuller]

If you buy Loctite 243 rather than the normally available 242, you don't need to clean the threads so much as it's oil resistant.

 

[Mr. Versatile]

Locktite is terrific stuff! I love it. I use it on my lawn mower, snowblower & roto tiller. It just can't be beat. I've never used it on any of my bikes though. If you grease the threads prior to assembly it has two advantages:
1. It makes the parts easier to disassemble
2. The grease fills in the tiny, almost microscopic spaces between the threads making the fastener much less likely to vibrate or work itself loose.

 

[jamesau]

I use blue for cleat fixing bolts and rear derailleur pulley bolts. These are places where bolt tension must be maintained by a low number of threads; this and past (troubling) experience are the criteria I use to decide whether loctite is applied

 

[RichardHead]

Loc-tite "Stick"??

I prefer the blue "stick" type, over the liquid. Lately, I haven't been able to find it in all the usual places. I ran across some from an online retailer, for $25!!!

Anyone know if this stick-type Loc-Tite has been discontinued??

 

[tom_h]

I prefer the blue "stick" type, over the liquid. Lately, I haven't been able to find it in all the usual places. I ran across some from an online retailer, for $25!!!

Anyone know if this stick-type Loc-Tite has been discontinued??

I haven't seen the stick for a while, but the thick gel might be an OK substitute
It's on the shelves of auto parts stores in So Calif (eg, NAPA stores).

Also available at Amazon for about $15

Permatex 24010E Threadlocker Gel Blue
http://www.amazon.com/gp/product/B000HBM564/ref=ord_cart_shr?ie=UTF8&m=ATVPDKIKX0DER