I had the great pleasure of trying to put a new Coker tire on an Airfoil rim today. It was extremely difficult. In fact, I couldn’t do it. I managed to get the Coker tire on without the tube just to see if the tire did indeed fit on the rim (it did), but I was unable to get the tire on with the tube inside. All I managed to do was invent quite a few new combinations swear words. It was clear it was going to be an impossible job by myself. I gave up and took the wheel and tire to my local bike shop to get their help. It was a two person job and required metal tire levers. They actually broke a plastic tire lever. Getting the bike shop folks to do my dirty work was the best $5 that I ever spent.
Is it normal for it to be so difficult to get a new Coker tire on the Airfoil rim?
Once the tire has been ridden I expect that it will be easier to get the tire on the next time. But getting that damn tire on the first time is more than I can handle without an extra pair of hands.
You might want to look at purchasing some Intense tire levers. You don’t want to go to the LBS everytime you get a flat. Mine was harder to mount then the original rim but with these (or equivalent) levers, it wasn’t impossible. Make sure the bead of the tire is sitting properly, you may have to over inflate the tire to get it on.
I didn’t have to install the tire on my Airfoil rim but I did have to go through the process of getting the bead properly aligned. That takes a bit of work as well. I was very glad I didn’t have to start from scratch.
The tips on this forum about the high pressure seating procedure were a great help.
It’s normal but not necessary. I do it solo with two plastic levers and a rubber band. I’ve been meaning to put a FAQ together but have been too busy. Basically you have to keep the bead in the center channel which has a much smaller diameter. At the end hold one lever on with the rubber band, and use your hands and the other lever to leverage on the rest of the tire. I’ll get the pics and text up as soon as I can.
It took me about half an hour to completely change tire, tube, and rim strip from 50 psi to 50 psi the only time I timed it. Personally I think that was very slow and expect to get that way down as time goes on.
Hi John - I haven’t had the pleasure of this tire/rim combination, but I have changed my fair share of motorcycle tires.
One thing that helps a lot is to warm up the new tire. This can be done by placing it in direct sunlight, or near (but not too near!) some other heat source.
If you go the route of using steel tire irons, buy good quality ones with a thin-section tip. The cheap steel ones are thicker at their tips which makes them harder to use and also places more stress on the rim. Motion Pro makes a nice tire iron, but it’s not cheap. Thin plastic rim protectors are also available to keep from marring your aluminum rims.
Professional tire shops use a liquid rubber lubricant which helps slide the tire over the rim, and also makes seating the bead much easier. Do NOT use dishwashing soap - it is slippery, but it will promote corrosion of your aluminum rim. The professional stuff (there are various brand names, “Tire Slip”, etc) comes by the gallon, is cheap, and should available at any automotive supply shop.
And as U-Turn points out, make sure that the diametrically opposite end of the bead you are working on is ALWAYS in the center section of the rim where the effective rim diameter is the smallest!
Ah, KnowFear reminded me… I always use silicone spray on tough tires. It comes in aerosol cans and can be found just about anywhere.
If necessary I wipe the rim down with some laquer thinner (or other solvent) after the tire is mounted to remove any silicone spray from the braking surface.
I’m aware of the trick of forcing the bead in the center channel of the rim where the diameter of the rim is smaller. That gives you more room to get the last bit of the bead over the rim. I was trying to keep the Coker tire in the center of the Airfoil rim.
My problem was the last bit of the tire over the rim. I’d get to the point where there was 1 to 1.5 feet of bead left to fit over the rim. I’d try to get the last bit of tire over the rim and the bead at the other end would slip out and I’d end up making negative progress. I needed another pair of hands to keep the bead from slipping out as the last bit of tire is forced over the rim. I couldn’t figure out how to do that by myself. I just needed another pair of hands.
I was using two plastic Quik-Stik levers and two metal levers that I use for my Gazz. I did dust the inside of the tire with talc, but I didn’t think of trying silicone spray. But I don’t think silicone spray would have helped. What I needed was an extra pair of hands.
Seating the bead was just a matter of inflating to about 80 psi, dropping the pressure, working the tire by hand, and inflating to about 80 psi again. It took a couple minutes but the bead popped into place. The shop had an air compressor so the inflating part was quick and easy.
I’m hopeful that the next time I have to put that tire on the rim will be easier now that the tire has been stretched and inflated. I know that my Gazz tires get easier to put on the second time around. But next time I try to put a new Coker tire on the Airfoil rim I’m going to make sure I have and extra person with me willing to help out.
Re: Re: Re: Putting a Coker tire on the Airfoil rim
Here are a couple of photos that show the rubber-band trick that lets you do it solo. The rubber band is a fairly long heavy-duty one that I got at the local hardware store. In addition, the plastic levers are Park brand and are very stiff (but still plastic).
In article <john_childs.v6hqq@timelimit.unicyclist.com>,
john_childs <john_childs.v6hqq@timelimit.unicyclist.com> wrote:
)
)My problem was the last bit of the tire over the rim. I’d get to the
)point where there was 1 to 1.5 feet of bead left to fit over the rim.
)I’d try to get the last bit of tire over the rim and the bead at the
)other end would slip out and I’d end up making negative progress. I
)needed another pair of hands to keep the bead from slipping out as the
)last bit of tire is forced over the rim. I couldn’t figure out how to
)do that by myself. I just needed another pair of hands.
The way I do this is to use one hand to hold the bead at one end, and
use the tire lever on the other side. So if you’ve got 12 inches of
bead to work with, hold the bead at the left side and put the tire
lever 2" or so from the right side. Lever that bit up, seat it in the
rim, then repeat, until the amount of bead is small enough that you can
attack it in the middle.
-Tom
I discovered a new trick for making the Coker tire easier to get on the Airfoil rim. The big problem I have is that the tire gets hung up on the edge of the rim tape. That causes two problems. It makes it difficult to get the tire down into the center channel of the rim while getting the tire on and it tends to peel the rim tape off during the install process. That makes it difficult to get the tire on and it exposes spoke holes.
I had to put the tire on again last week. This time I put little strips of strapping tape (clear packing tape with fibers running the length of the tape) in the rim to tack down the rim tape and keep the rim tape in place. I cut sections of tape wide enough to cover the whole width of the rim and tacked down the rim tape every couple of inches. That made things MUCH easier. The tape is slippery so the tire easily slides into the center channel of the rim during the install process and the rim tape stays in place with no issues. Installing the tire was really easy.
De ja vu! That is EXACTLY what happened to me, right down to them breaking a plastic tyre lever. It was definitely a two person job. I finally got the tyre on but realised the rubber rim strip had moved away from the nipples so I had to take it off again and replace the rubber strip with insulation tape.
The bike shop had this nifty device called a tyre jack which helped with mounting the tyre. I had never seen one before but it was basically a hand held lever type tool which looked a bit like an oversized pair of grips. The tyre jack hooked on to one side of the rim and then the jaws went over the tyre, gripping the other side. As you squeezed the handles it helped lever the tyre onto the rim.
The tyre jack they had was not quite big enough for the wheel TA tyre, but with two people holding things we got it to work. A slightly larger one would make changing a coker tyre a lot easier. All power to the right tool for the job.
They mounted the TA tie on the airfoil for $10.00**. They admitted that they had a hard time, and it took two people. I was disappointed that they mounted my of stock Coker tube instead of the 29" tube I had in the wheel when I brought it into the LBS. But now I’m thinking it’s better to have the tough tube in there, that will last.
Coming from the LBS the wheel was a wreak. Spokes were loose, and the wheel was untrue. The wheel must have been really stressed with the tire mounting but more likely that I must not have done such a great job building the wheel. The airfoil trued right up nicely and the spokes seem plenty tight now.
**Not as good a deal as John_Child’s, but I’m happy.
I just mounted a official ‘Coker’ tire on my airfoil rim with just my hands. It was very very easy. No tricks, I used the rubber rim tape (band actually) from a steel Coker rim, and the big Coker tube.
(The airfoil rim is the same one I could not get the ‘TA’ tire back onto myself, the B*ke shop said it took two people to mount it.)
I haven’t tried mount the 29" tube with the ‘Coker’ tire. I had just finished putting the lighter stainless steel spokes on the rim, and sorta got anxious to try the new build so I put off fussing with the 29" tube.
My Coker is beginning to feel light enough with the lighter stainless spokes (from Tom Miller), lighter Airfoil rim, lighter Coker tire, and lighter 150mm torker LX alloy cranks. I may not deal with the lighter 29 inch tube.
thats odd, I didn’t have any trouble at all, actually I was surprised how easy it was…I just took the tire and tube and rim tape off of my steel rim, and put them on the airfoil.
It actually is easy to install the tire on an Airfoil rim if you only install the tire without a tube or rim tape. Even with my problem rim and tire combo I had no problem getting just the tire on. The difficulty comes when you get the tube and rim tape in there, actually it seems to be the rim tape that is most of the problem.
If you’re using the rubber rim strip that comes with the standard Coker wheel be sure to check that the rim strip is still covering all of the spoke holes after mounting the tire. You can push one side of the tire over and look inside. It is very easy to push the rim strip or rim tape out of place while putting the Coker tire on.
