Cyclocross Tubular Gluing – A Newbie’s Brain Dump

This year I decided I needed to learn how to glue my own tires. Youtube is wonderful, and I checked out a lot of different videos and read a lot of different articles about the hows and whys. Instead of going really deep into detail, I’m going to reference the two videos I relied upon the most, and then throw in a few more tidbits and observations.

Primary source, which I believe is the Stu Thorne method, basically:

Supplemental source with good info and explanation, answering many of the “whys”, from Michael Robson/Butter:

 

A brief overview of what you need, besides tires and wheels:

  • Acid brushes
  • Glue (I used Vittoria Mastik One in a can)
  • Nitrile gloves, but these are not critical, IMO
  • Truing stand
  • “Belgian” CX tape (OPTIONAL)
  • Broom handle
  • Apron

First Attempt

My first attempt involved re-gluing Clement PDX tires to the same Mavic Reflex rims. As you may be aware, Reflex rims are old school, narrow, box-section rims. After wrestling the tires off carefully, I needed to remove a ton of glue. The previous glue job was all glue (no tape) and plenty was left over on the rim bed that needed to be taken off to prep the surface adequately to receive the new layers.

dirty-rim

For glue removal from alloy rims, skip all other recommendations and go straight to the heat gun method.  All other methods will at a minimum take much, much longer, and a lot more effort. I tried using a hair dryer and Goof Off with a butter knife and popsicle sticks. Forget that noise. Just go and spend 25 bucks on the basic heat gun at the hardware store and use that. I was able to get down to the bare rim, or close to it, with maybe 30 minutes of effort (max) per wheel. The benefit of the glue gun is that, even if you don’t get all of the big chunks of old glue off, it melts it down to the point that, when you wipe it off with your rag/towel/whatever, it will smooth out whatever glue residue you don’t get off so that you at least have a smooth surface upon which to start re-gluing.

cleaning-rim

There was not a lot of residual glue left on the base tape of either of my tires, so I just picked the biggest hunks of glue off from a few spots, then I roughed them up a bit with a large file. I didn’t go crazy with this part.

I had everything set up to use a 5 coat method, with Belgian tape. This is (as recommended in the first video above), two layers on the tire, two layers on the rim, add tape to the rim, then a final 5th layer on the CX-taped rim right before mounting.

The deal with Reflexes is that they’re old-school narrow, so the CX tape that I was using took a bit of extra effort to get into the rim bed straight. I was able to get both tires on their rims on the first try.

Mistake Number One

The first tire went well, but I did not stretch the second enough from the beginning of the mounting step, and it became difficult to get on at the end.  As a result, I had to really, really wrestle with it to get it straight, and this ended up causing a botched tire/rim connection at that point of the wheel.  After waiting a couple of days to set up/cure properly, I was still able to pry the tire off with my hand pretty easily in that section.  As a result, I yanked it all the way off and started over. More practice, no biggie.

botched-glue-job

Mistake Number Two…Sort of

I ran out of CX tape after the first two wheels, and my new shipment was going to take a few extra days. I didn’t feel like waiting for the tape and decided to re-glue the aforementioned botched wheel using a glue-only method. I figured, this would be a good opportunity to test that method, and I could always retry if it wasn’t solid.

I went with extra thick layers this time around, taking care to use as much glue as I could on both tire and rim without it being an uneven mess. During this attempt to mount the tire, I took extra care to stretch more from the beginning (outwardly from the valve stem), and it went on much better. The extra step I decided to add in here which is NOT mentioned in either video above is using the broom handle in the rim bed to really mash the tire and rim glue surfaces together.

I did not use the broom handle on the first tire I mounted up, and they have both proven to be similarly strong bonds so far.

Second Set of Wheels

I did a second set of wheels a week later, using new FMB tires and NOS wheels with Velocity Major Tom rims. Because the Major Toms are wider than the Reflexes, the CX tape went on a bit easier and more solidly. There was just more space for the tape and it was easier to mash in there as a result.

The step I missed with these wheels was cleaning the new rim surfaces with acetone before applying the first layer of glue.  The wheels I was using were clean and relatively dust free, and they have been solid so far, so I don’t think this step is critical. If there’s any question about the cleanliness of a new rim surface, it’s probably a good idea not to skip that step though.

With these wheels, I put the “glue them as fast as you can” method espoused from the first video above to the test. After gluing a set, screwing up, then fixing one, I felt pretty comfortable with my ability to recognize if the job I was doing was insufficient. While I was not able to do them quite as fast as the guy suggested I would be able to, I did finish these wheels in a little under 4 hours total time (in one sitting). I used the 2 layer/2 layer, then tape, then a final bonding layer method, then finalized the job by mashing them together with the broom handle.

Final Thoughts, Leftover Notes, etc

In summary:

  • Glue only works fine. I say this having used that method for the front wheel on Mavic Reflex rims, which are narrow with a relatively shallow rim bed. I _did_ finalize the bond with a good bit of effort with a broom handle.
  • CX tape appears to work equally well, and may prove to be superior over time. I’ll reserve judgment until I have more time and a wider array of conditions on both sets.
  • You really don’t have to let the glue cure 24 hours, overnight, or really any longer than it takes to harden a bit. I found that about 15 minutes would be plenty of time in average working conditions. Just glue and move on to the next one!
  • I personally would not use a heat gun on carbon rims.  I’m not a carbon rim guy, so I let the alloy Reflexes have it pretty good. I’ve heard from other friends that using heat on carbon is fine, but I’m sure the manufacturers would probably not advocate it. I won’t go there.
  • Don’t forget to let some air out of the tires after you glue the base tape layers.  I forgot to do this with one of my tires, and as a result, I think it’s eeeever so slightly lop-sided, with the tread leaning just a skosh. It could be a tire irregularity or a mounting error, but I suspect this was the issue. I would inflate the tire to whatever you need to apply the glue, then let out enough so that it just has enough air to maintain its shape.
  • I really like the way Clements mount up, they’re very easy to get on straight (relatively speaking).
  • I have 3 races on each set this season – so far so good. I continue to check the bond each week before I race. I empty each tire almost completely, then I give it a good wrenching with both hands, all the way around the wheel on both sides. This is basically part of my weekly race prep routine – I should have been doing that before!

Please feel free to hit me up with questions, happy to share whatever I’ve learned.

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