A lot of people get freaked out by tubulars. They have heard horror stories about rolling tires and the painful $100 flat. They think it's messy and difficult to install tires. And to a degree those stories are true. There is a cost of doing business with tubulars, but oh what a business it is.
First, the benefits. Blah blah modern clinchers yadda yadda latex tubes lorem ipso e pluribus unum. The road (grass/mud/gravel) feel of tubulars beats the pants off of the best clinchers. I could blind taste test this and bat 1000, easily. Of course I would run into stuff and fall over and possibly cause more school absences so I don't want to do that.
It's also REALLY hard to pinch flat a tubular. I used clinchers at one of my favorite races (Poolesville) last year because I didn't want to flat a tubular so close before Killington. What happened? I pinch flatted at Poolesville, but while using tubies at Killington I hit 10 things as bad or worse than what did me in at Poolesville with no flats.
In cross, you can run crazy low pressure with tubulars, which gives you insane traction. This is a good thing.
That said, I saw a LOT of rolled tubulars at Kinder Kross last weekend. Why? Tough saying without knowing but I think it's all down to bad prep and technique, so I'll walk you through gluing a new tubular on a new wheel. I'm no one's super genius but the wheels I've glued have stayed put through thick and thin. Here's how I approach it. Your mileage may vary and you might be all thumbs, so I offer no guarantee other than to tell you I've never had a problem.
First, the materials list. You need:
-
Acetone - Tubular glue (Vittoria or Continental)
- Flux brushes
- 120 grit sandpaper
- Clean rags
- Solvent proof gloves
- Tire pump
- Valve extenders
New tires are TIGHT, so before anything else you're going to stretch the tire. Wipe the rim clean with acetone and a rag (wear the gloves, your kidneys will thank you) so you don't get any leftover oil from the wheel build embedded in the tire, install your valve extenders if needed, and stretch the tire onto the rim. Pump it up to 80 psi and leave it overnight.
When that's done, remove the tire from the rim and clean the rim again. For metal rims, I do a quick pass over the rim bed with the sandpaper to scuff the surface, then clean with acetone. Paint one thin layer of glue onto the rim. The edges of the rim bed are FAR more important than the middle. Be neat and avoid getting glue on the brake track. Thin coats are better. The edges. The edges.
Inflate the tire enough to give it shape and grab it in the middle to give it a figure 8 shape. Paint the base tape from edge to edge with glue. Thin coat, and going over the edge of the tape is fine.
Let both rim and tire sit for 24 hours, then repeat the exact same process.
Before installing the tire, you're going to deflate the tire and put a third coat on the rim. Then stand the rim on the ground with the valve stem hole at the top. Make sure that your tire's tread is facing the right way!!! Insert the valve stem through the hole and begin stretching the tire down onto the rim. When you're most of the way on, flip the wheel over and finagle the rest of the tire on. Then put just enough air into the tire to give it shape and get the tire straight on the rim. Use the base tape as a guide but on a lot of tires the tread sort of wanders in relation to the base tape. You want the base tape in contact with the rim and the tread as straight as possible.
Most cross tires are a little lumpy, so you want to stretch the lumps out. Just push away from the lump on either side and it will minimize.
Once you're happy with the tread orientation, pump the tire up to 80 psi and leave it for 24 hours. This will really create a strong glue bond.
I do not use Belgian tape for either road or cross. Since all of our rims have wider rim beds, I don't think this is necessary and I'm loathe to screw with what works.
We'd love to be able to offer this as a service, and we meant to. Unfortunately a few stories about shops getting sued by people who rolled tubulars (the decider was the guy who stored a wheel for three years and then used it without getting it reglued - OF COURSE the glue dried out and became useless in three years) put us off of this completely. Even if our insurance covers it, I have no interest in spending days or weeks or hours in court dealing with it. Even if we're super confident of our technique - enough that I send the would-be mother of my would-be children out every weekend on tires I've glued. Even though you are not the type of person to sue, someone else definitely is.
7 comments
Bert – Once. One time. Brian – Do NOT sand carbon rims. Let me remove any ambiguity about it. Don't do it. For any reason. We did want to offer gluing as a service but have decided that potential liability is too great, so any references to the service will be removed as we find them. As for stretching, the outstanding immediate thing is that we can't ship them with any air in them because they fly cargo, not coach. I'd love to watch a movie of what happens to a tire with some air in it when it gets to 20000 feet, but not if the movie starred my wheels and tires and I was on the hook for the consequences. Also, I've nearly broken thumbs putting new cx tires on rims. Plus liability – if a tire that someone glues rolls, is it because I stretched it (which is an expensive question to get asked by a lawyer, even if the answer turns out to be 'absolutely not') or whatever other potential liability issues. Our impulse to always do special stuff that seems to make sense sometimes crashes on the rocks of the way the world is.
Dave, most cargo planes are pressurized to 8,000 or 10,000 feet, which is just about 2/3 sea level air pressure or so. They're typically not temperature controlled, so the lower temperature, and lower external pressure counteract each other. Still not a good idea to ship tires with air in them, but it's not as drastic as you think.