Glues, Spooges and $hit like that…

So as MTBrs, we’re undoubtedly going to run across times when we need to glue something together… could be our favorite pair of MTB shoes to get a few extra miles out of before replacing, could be a slice in a tire sidewall, could be our frame that we got welded and are now stranded out in some remote place (Looking at you Schilling).

What I’ve noticed as I’ve talked with many of you reading this, is that you choose a substance that may not really be the best thing…I mean lets face it, we have ready access to stuff like JB Weld, Shoe Goo, Super Glue, lots of 2 part epoxies, silicone, etc…But, they are all made for VERY different purposes.  So this little blog write-up is to hopefully add some logic based on my experience but also my mechanical engineering know-how from working with some of these things in my past life.

Shoe goo

Shoe goo is amazing stuff, rubber in a tube that gets you really high (note: use in a well ventilated space) but gets mistakenly used as a bonding agent.  It is NOT.  I would highly discourage using the stuff to bond two things together since that is NOT what it was designed to do.  It really doesn’t have great bond strength.  It’s basically a wear surface to replace worn off parts of your shoe.  Sticks great to rubber, but not so much to other highly flexible parts of your shoe (like the uppers).  I have applied this to the underside of my mtb shoes WHEN THEY ARE NEW to lengthen the HAB life of them.  Below is a pic of two of my pairs, both of which are at least 3 years old, the Shimano’s having been HAB’d up Mingus 2x and been through the AZT300.   Obviously, you have to clean the surfaces to which you apply it and it will tend to flow so you can’t lay it on too thick.  But, the stuff is great when used for what it is intended.

Great for parties and making your shoes last longer

I put on Shoe Goo on these SIDI's when they were almost new and have not worn through the toe yet....still going strong.  I'm sure the socket head cap screws used as toe spikes helped too.

Another view of the SIDI's... note that that it doesn't stick to the leather very well due to the flexing

These are those Shimano M089's that have been to hell and back..again, I put the stuff on early in their life...well before the toe area got too worn down.

Here again, note how the shoe goo does not stick to the uppers very well.

Superglue

Superglue has a ton of uses for MTBing….keeping skin stuck together, gluing your buddies ass to the toilet seat, etc… lol…Superglue is obviously a GLUE(duh)…a bonding agent (Cyanoacrylate).  They work when the stuff you are bonding is fairly rigid AND the bond line is THIN.  They don’t fill gaps very well.  Below you’ll see a pic of a pair of my somewhat new Shimano’s that have an inherent design flaw where the sole next to the cleat delaminates.  This happened the same way in the pair I discussed earlier that has been through tons of HAB.  The solution (which works EXTREMELY well) is to use some superglue (the cheap stuff from Harbor Frieght), let it wick into the joint, but then clamp it with some spring clamps to keep the bond line tight.  If you were to try and fix these with shoe goo or some other flexible adhesive, you would probably have issues.  Where superglue falls down is when the surfaces flex a lot, ie, tire sidewall slices.  However, some manufacturers have formulated more robust cyanoacrylates (gorilla glue) that can flex.  Personally, I have not tried these.  Hutchinson has a tubeless tire patch kit (that they are quite proud of) that has a specially formulated superglue for bonding rubber…

I'm a fan of the cheap stuff at Harbor Freight...used correctly, it works great

Note the slightly darker area right of the cleat...that's the superglue where I bonded down that sole ridge.

Using a spring clamp to keep it tight

This shoe was glued EXACTLY like above very early in its life...it never failed after bonding it with cheap a$$ Harbor Freight Super Glue

2-Part Expoxies

There are of course a ton of these ranging from quick cure ones to not so quick.  Things like JB Weld are 2-part epoxies.  Typically these cure very rigid but also have great bond strength with metals, plastics and carbon (stuff we find on bikes).   Below is are a couple of pics where I used it to repair a set of carbon bar ends that after multiple crashes, had worn through the carbon.  They are definitely not made for flexible materials.  I did end up fixing a set of saddle rails with it, but in the end did not use it since I had a replacement.  I’m pretty confident it would have worked fine.

My cheap Chinertown carbon bar end that started to crack from too many diggers

5 bucks worth of 5 min epoxy...works great...get it at HD.

Silicone

Silicone actually has more uses than just to seal bathtubs and make boobs bigger…I have had great luck using it to repair cut tires.  For example, we all have cut a sidewall at some point and later get it home and patch the inside.  Sometimes, the cut is barely through the sidewall or even the patch we use might be “just” big enough.  I will take pure silicone, and smear it on the inside of the tire over and beyond the patch or over the cut.  It adheres quite well to the inside of tires and when it sets up, will not extrude itself through the cut or puncture in the tire.  Obviously, it’s not a very robust wear material so if you put it on the outside of the tire, it won’t last too long. 

No, not this kind of silcone ya bunch of perverts

So, there you have it…a quick brain dump on glues and such.  I’m positive I don’t know everything about this, and you all have info to add.  But, hopefully this helps a few folks buy the right spooge for their need.