Mounting Tires on i180 Wheels
From SegwaySocial
Contents |
Outside Edge
Start mounting the tire by inserting the wheel into the tire so that the outside bead rests in the dropwell. On the new i180 wheels, the valve stem is girded by reinforcements across the dropwell, so position the wheel so that the bead doesn't rest against these reinforcements.
The inner rim of the Segway plastic wheel is stronger than the outer rim, so insert the inner rim from the outside face of the tire as shown. In this way, any installation forces used to install the tire will be applied to the inner (and stronger) wheel rim.
The next photo shows what the tire will look like once it has been installed over the inner rim.
Over the inner rim
Here's what the tire looks like once it has been installed over the inner rim.
Getting to this stage should be easy and doesn't require a large amount of force or any tools. If you have difficulty, make sure the tire bead is deeply seated in the opposite dropwell as you pull the bead over the rim with your hands.
The next step is to pull the inside bead over the inside rim.
Inside bead over the inside rim
Position the Tire in the Dropwell
To mount the inside bead, begin by lubricating the tire bead and rim with soapy water applied with a small brush or a rag. This will help ease the bead over the rim in the next few steps.
Now pinch the tire's sidewalls and push as much of the tire as you can into the dropwell (opposite the valve stem again). Note that both sidewalls are inserted into the dropwell. You should be able to get about half of the tire's the circumference below the rim with just your hands. As you proceed with the steps below, take care to not allow the tire to slip out of the dropwell.
Use the Tire Levers
Next, push two tire levers between the tire bead and the wheel as shown so that the hooks on the levers engage the wheel rim. One of these levers will be used to do the work, while the other is left stationary to keep the tire bead from moving above the rim. Until you are practiced at this procedure, you may find it helpful to have an assistant hold the stationary tire lever for you so that it isn't pushed out of position as you complete the next few steps.
With the tire levers in the position shown, pivot one of them on the wheel rim and pull a small section of tire bead over the rim (see the yellow arrow in the photo). Remove the tire lever and reinsert it a couple of inches away and pull another small section over the rim. In this step, you are not stretching the tire over the rim (it won't stretch), you are actually pulling the adjacent tire bead deeper into the dropwell. It does not take very much force to lever a small section of bead over the rim. If you can't easily pull a section of bead over the rim, hold some tension on the lever and work more of the opposite tire bead back into the dropwell.
Continue repositioning the lever to pull successive sections of tire over the rim a few inches at a time. The next photo shows what the tire will look like when you are almost done mounting.
Ready for the Big Push
This is what the tire will look like just before the last section of bead slides over the rim. Note how much of the tire has been pulled into the dropwell.
Now push the last little bit of tire bead over the rim with your hands and remove the tire levers. The next step is to seat the bead and inflate the tire.
Seat the Bead, Inflate the Tire
Clean It Up
Start by cleaning the rim of the wheel and the tire bead with a rag. Take your time and inspect the bead and rim carefully. These two surfaces must mate to each other with an air-tight seal, so any dirt left here will probably result in a leak later on.
Before Inflation
If you immediately tried to inflate the tire, you'd probably find very large gaps between the tire and the rim and it wouldn't hold any air. The following procedure prepares a tubeless tire for inflation.
Hold the tire and wheel vertically and bounce it on the floor. Each bounce will force the sidewalls and tire bead towards the rim. Rotate the tire and wheel to a new position and bounce it again until the entire circumference of the tire has been pushed closer to the rim. This doesn't take a lot of force — the weight of the tire and wheel is enough to do the work.
Inflate the Tire
Now begin to inflate the tire with a hand pump or an air compressor. Make sure your fingers are clear of any gaps between the rim and the tire bead. As more and more air is added to the tire, each bead will push out towards the rim and seat with a loud snap! The maximum air pressure rating for the tire is usually sufficient to seat the bead. If I'm using an air compressor for this step, I leave the valve core out to reduce the likelihood of over-inflating the tire. Don't despair if you don't have an air compressor — I've used this technique to seat the bead on automotive tires with my trusty Schwinn bicycle pump.
Check for Centricity
Once the beads on both sides of the wheel have been seated, examine how the tire is positioned on the wheel. The tire should be centered on the wheel with an even gap all around the tire bead and wheel rim. If the tire is not centered, release all but a few pounds of air pressure and re-center the tire by moving it into place with your hands. I didn't encounter this problem using Segway tires and wheels, and I doubt you will either. A tire that is not centered on the wheel is more likely when the edge of the tire bead doesn't lay on the rim shell.
Check for Leaks
Soap Bubbles
Tubeless tires will not usually hold air immediately after they are first inflated. By inflating the tire to its maximum rating, the soft rubber on the bead will more quickly conform to the wheel rim and create an air-tight seal.
After the tire is inflated, I brush some soapy water along the rim to help detect leaks. I expect the tire to leak, but what I'm looking for are really large leaks. The small soap bubbles in picture above reveal an acceptable leak right after the tire was inflated — this leak stopped within a few minutes. I usually leave the tires inflated to their maximum pressure overnight, then deflate them to the proper value the next day.
Repair Persistent Leaks
If you do detect a big leak or one that just won't stop, the cause is likely a defect in the tire bead or rim, or dirt between the two. If dirt is the cause, cleaning the tire bead and wheel rim should eliminate the leak. Sometimes, you can repair a bead leak by simply rotating the tire to a different position. Both of these repairs will likely require you to break the bead . . . great incentive to ensure the bead and rim are very clean before you seat the bead!
Finished
To finish up, use a damp rag to remove any remaining soap solution from the tire and wheel.
