I have a tough application (motorcycle kick start lever) where I'm using a grade 8 1/4 - 20 bolt in some pretty tough threads. I don't want the bolt to budge after it is tightened but it may need to come out at some point in the future. I am using a lock washer but should I use red or blue loctite?
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Red or blue loctite
- Thread starter yellow_cad
- Start date
Not knowing a lot about the construction of a motorcycle kick lever, I am assuming the 1/4-20 is holding the lever on, and some sort of additional mechanical device (spline, dog clutch, etc) is taking the torque. If that is the case, I would go with the blue. Blue Loctite is meant to be removed, but will prevent fasteners from vibrating loose. Red loctite is more or less permanent unless you break out a torch. With enough thread engagement you will twist the head off before get the fastener out.
If you use red and need to remove the shifter you'll have to heat it and probably rig up a gear puller. Chances are you'll need to replace the shifter seal due to the heat. I think blue will take care of youe needs. If you're concerned about the bolt backing out, bore a small hole thru the bolt head and use stainless safety wire to secure it. Hope this helps. Roger
Blue.
In general, blue is removable, red is much more difficult to separate - sometime requiring heat. That said, there are several "blue" Loctite's with 242 being the most common IMHO and several "red" Loctite's with 271 being the most common. You really should specify by number...
If you REALLY never want something to come apart - use Loctite greeen 290 which is a wicking grade compound, but apply it to the threads as you would any other Loctite... According to the Loctite rep/trainber/apps engineer - no locking compound with work well unless the parts to be secured are VERY clean and preferably primed with Loctite primer: http://www.henkelna.com/industrial/loctite-quickstix-7088-primer-6827.htm
John
If you REALLY never want something to come apart - use Loctite greeen 290 which is a wicking grade compound, but apply it to the threads as you would any other Loctite... According to the Loctite rep/trainber/apps engineer - no locking compound with work well unless the parts to be secured are VERY clean and preferably primed with Loctite primer: http://www.henkelna.com/industrial/loctite-quickstix-7088-primer-6827.htm
John
Blue 242 is the correct grade for a MC. Clean the bolt and the hole well, apply one drop, allow the drop to spread to the tip, insert bolt and torque to spec. Done. Most issues with loctite are from using too much and not properly cleaning the fastener. It is an anaerobic thread lock compound, meaning it sets in the absence of air and a thin film will set up and hold best when no trapped air or contaminants are in the connection. If applied correctly and properly cleaned Blue 242 will hold any bolt you might encounter. Red is for semi-permanent application and also if properly applied will require heat to loosen. Green is another story entirely, but suffice to say cosider it permanent when you assemble it because it is unlikely you will ever get it apart successfully with common tools without damaging the item... This all assumes that the loctite was installed properly to begin with.
Bob
Bob