I discovered a trick that makes getting the Coker tire on an Airfoil rim really easy (well, much much easier). I’m using a 29er tube now in my JC Coker (Schwalbe tube).
I use fabric style rim tape. About 16mm width. Get the rim tape snug in the rim.
Then I use strapping tape over the rim tape. I cut the strapping tape to be wide enough to cover the bottom of the rim, pretty much from sidewall to sidewall.
The strapping tape is slippery and makes it much easier for the tire to slide down into the center channel of the rim while installing the tire. The big problem I have is the tire getting hung up on the edge of the rim tape. It will peel the rim tape off or just get hung up and not slide down into the center channel of the rim. The strapping tape solves that problem.
The strapping tape does not need to cover 100% of the circumference of the rim. I covered about 70% to 80% of the rim and that was plenty. I cut short strips a couple inches long so they would be easy to apply. Then went around the rim piece by piece.
Then a little Silicone spray lubricant around the bead area of the tire and follow U-Turn’s instructions for installing a 29er tube in a Coker. Oh, and talc on the tube helps too.
With the strapping tape over the rim tape it was really easy to install the tire. It felt like it would be completely possible to do it by hand with no tools. The thought of needing to repair a flat or replace a tube is no longer a scary thought.
Next time I take the tire off I’ll try to remember to take pictures of the strapping tape. The description should be explanatory enought, but pictures are worth 1000 words.
I use a fabric style rim tape that is the kind they use on mountain bike tires. i have to tape one on and they use part of another to get all the way around the rim. Is that the same kind you are talking about, John?
What is strapping tape? Clear-plastic tape used to tape up a cardboard box?
I use the MTB or road bike rim tape like Velox brand. It takes a little bit more than one roll to do a Coker rim. Bike shops can get the stuff in bulk in a big roll and just cut off the length that they need. So a bike shop would be able to wrap a Coker rim with a single piece of rim tape. Us normal people generally have to use the prepackaged tape that is just a little bit too short to fit all the way around a Coker wheel with one roll.
The strapping tape is the stuff you have pictured. Scotch Strapping Tape that has the threads running lengthwise all along the length of the tape. I used the 2" wide stuff in the second picture you had posted.
You can rip the tape lengthwise and the threads will act as a guide to get a smooth tear all along the length of the tape. I had problems getting long pieces to fit smoothly inside of the Airfoil rim so I had to use short pieces and lots of them.
Just bring along a spare Coker Tube in case it does blow up. That’s what Bronson did on the AUT when his 29’er tube started deflating, and what I used to change my tyre over when it wore out- I didn’t have the high pressure compressor or enough no-tubes sealant to configure back to tubeless on tour.
If you are after a light wheel (the whole point of the 29er exercise), then I’d stick with the Coker tyre- it’s lighter than the TA apparently.
To be honest, whilst it’s a noticeable difference, the trouble required with a 29’er configuration almost makes me wonder if it is worthwhile.
I didn’t have any trouble with the rim tape. Whatever’s in there isn’t moving around. The tube doesn’t slide on it easily, but it doesn’t seem to need to.
I’ve removed and replaced the tube three more times since trashing those first three and I haven’t had any more problems. The big change was to use dishwashing soap to lube the bead area of the tire, just like what John suggested with silicone spray. It makes the tire slide over the lever easily, which means the lever doesn’t have to move as far before the tire can be convinced to move into the rim, which means the lever won’t pinch the tube.
But after all that hard-won experience and scratching the rim, I think I’m going to stick with a 36" tube. I managed to ride on a patched 29" tube for an hour before it deflated and I didn’t feel much of a difference, so I’ll stick with reliability. (Slime didn’t help either, so I have to assume that a flat would often mean changing the tube.)
I got the whole process (including getting the wheel off and on past the brake) down to 40 minutes, but it’s a lot of work. I’ve had enough of fiddling with the gear. I’d rather be riding.
