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How To Glue Tubular Tires for Cyclocross: A TBD Guide

You’ve decided you want ride tubs for cyclocross season, just like the pros in Belgium. But now you have a problem: At least in New York, shops that glue tubulars with the right methodology for CX are few and far between. For example, in cross you run tires at very low pressures—15-20 psi on a muddy day. Unless you’ve glued the tubs exactly right, they will roll off. Some shops, like Brooklyn’s King Kog, are great at this. But most aren’t, sadly. Many riders on TBD decide to glue tubs DIY. At least if they roll, you only have yourself to blame. 

We prepared a handy guide with input across TBD with our best practices for gluing tubular tires specifically for cyclocross so you’ll never roll a tub again. Here goes: 

Prerequisites: 

  • 1 set tubular wheels

  • 1 set tubular CX tires 

  • Clean rims - if your rim still have glue on them from a previous tubular, they aren’t clean enough yet. You need to clean them before you proceed. See our guide to cleaning tubular glue/tape from wheels (coming soon).

  • 1 can Vittoria Mastik (250g)

  • Paint brushes (try an acid glue brush)

  • Stu Thorne Belgian CX Tape (There are many imposters on Amazon, but this is The One) 

  • Spray bottle full of alcohol (not the drinking kind)

  • Clean rag

  • Workspace with newspaper on floor 

  • Masking tape or painter’s tape

Guide to gluing CX tubs

Step 1 - Preparation 

Clean your rims. *

On a clean rim surface (with no glue), stretch your tubular tires onto the rim (without tape or glue) and inflate to max PSI. Ideally, let the tires stretch on the rim for at least a week, if not longer. The longer the better, and the easier they’ll be to mount after you put glue on. 

Step 2 - Gluing

  1. Spray rims with alcohol and wipe down with a rag. They should be near pristine, no traces of glue (or very, very rare traces). Especially no traces of dirt. Let dry for a couple of minutes. Then … 

  2. Apply a layer of masking tape or painter’s tape to the side of the rims. The goal here is to avoid glue getting on your decals and generally making a mess on the sides of the rim. 

  3. Apply one thin layer of Mastik on wheel rim. You may want to twirl the brush after you dip it to avoid strings of glue trailing from the can to the rim and back. 

  4. Apply one thin layer of Mastik on the tire. Fold the tire (as shown in photo) to hold with one hand and use the brush in the other. 

  5. Pause & let dry for 8-24 hrs.

  6. Then start again.

  7. One thin layer on wheel rim (2nd layer).

  8. One thin layer on tire (2nd layer). 

  9. For extra credit, you can pause and let dry for another 8-24 hrs. Or just wait 2-3 hrs and then start mounting with process below.

  10. Mount a single layer of belgian tape on the (now dry) rim. There should be no creases and relatively tight without breaking the tape. Do this on both rims before you move on to the next step. We’re almost ready to mount. 

  11. One more gloppy glue layer on rim. 

  12. One more gloppy glue layer on the tire. 

  13. Finally, as quickly as possible before it dries, mount the tire. 

Step 3 - Mounting technique 

This is more art than science. If you’ve stretched the tire properly, this should not be awful - just hard. The longer it takes, the harder it becomes to get everything straight. A few tips: 

  1. Wear gloves. 

  2. Deflate the tire as much as possible before mounting. 

  3. Start by putting the valve carefully into the rim and hold the wheel with the valve on the high side, pointing down to the floor

  4. Align the base tape with the channel of the rim as closely as possible 

  5. Stretch the tire around the wheel as you mount it, guiding the base tape exactly to align with the rim channel

  6. As you get toward the final section, you’ll feel the tire stretching tight and more resistance to mount it. 

  7. Depending on hand strength, how well you stretched the tire, and how much air is in the tire, this last part can be easy, hard, or awful. 

  8. Do whatever you have to do (using your hands and body leverage) to get the final section of tire on the rim as quickly as possible. It’s ok if it’s rotated weirdly in the final section as long as it’s on. 

  9. Once you get it on, quickly rotate the tire so the base tape on the top section is aligned with the rim channel. 

  10. Now get a compressor (or regular) pump and blow up the tire to max psi asap. This will naturally align the rim and the base tape. Spin the wheel to see where you need to straighten/correct. Deflate to correct major misalignments that still exist. Spin again and correct until the wheel and tire spin true at low psi (e.g. 15).

  11. Remove the masking tape.

  12. Wipe down any extra glue on the sidewall of the tire or the rim. 


Step 4 - Wrap up & testing

Let the wheels sit to dry for at least 4-5 days. Best case, if you live in a dry, low humidity climate, put the wheels outside in the sun for 12 hrs or so to have the glue in the base tape and rim melt a little as they bond. Four days can be a little excessive — it is possible to ride (or race) on freshly glued tubs within 24 hrs. BUT, the cement isn’t actually fully dry until 78+ hours. So best case, wait longer. 

When you ride the wheels for the first time, test the tires! Rail 20+ fast, off-camber turns with a leg out/tripod and low pressure (e.g. 16psi) … and make sure the tires don’t roll off. If they survive this test, you’re good to go. They’re not coming off for a long time. 

* Someday we’ll write a part 2 that covers how to take these bad boys off and clean the rim so you can do this again. But not today.