Tires are something every moto-maniac has a different opinion on; what you hear come up often is tire bead.
You may have heard some small talk around your buddy’s garage about blown tire beads or ripped beads casing leaks, but what exactly is a tire bead, and what are some of the things that cause a motorcycle tire not to bead?
You’ve come to the right place; today, we’re here to list the reasons why a motorcycle tire won’t bead!
First, for some of the riders still imagining what a tire rosary looks like, let’s start with the basics.
What’s a Motorcycle Tire Bead?
The tire bead is the part of the bike’s tire that contacts the wheel’s rim and therefore is reinforced, as its liable for forming the air seal between the wheel and the tire.
What Does a Motorcycle Tire Bead Do?
A motorcycle tire bead creates the seal from the friction between the bead and the wheel rim, while a steel or copper strip supports the bead in maintaining the seal during severe motorcycle vibrations or tire distortions.
Where Is a Motorcycle Tire Bead Located?
The motorcycle bead rests along the tire’s inner edge, right where the tire meets the wheel. The bead runs along the “inside” of the tire instead of the outside tire tread.
On an installed tire, the bead is easily found along the base of each sidewall, where each sidewall meets the tire.
On an installed tire, the bead should be hidden behind the edge of the wheel unless there’s significant damage to the wheel, tire, or the bead’s seal.
Ok, now that we got the basics down, let’s go into the primary reason why a motorcycle tire won’t bead!
1. Bike Tires Are Over Inflated
If your motorcycle tires are over-inflated, the increased tire mass could cause the tire bead to slip out of the position required to achieve the proper bead seal.
If the tire is over-inflated past a certain point, a slip could cause a damaged bead seal that mysteriously leaks air until it’s addressed.
It goes without saying that you should never over-inflate your tires on purpose; why would you, right?
I’ve known some brave riders who try to “pre-inflate” before changing elevation, so their tires deflate to the ideal PSI.
There’s never a good reason to over-inflate your tires past the spec PSI; bead failure is just one of many issues that can pop up on an over-inflated tire, pun intended.
The raised tire walls risk bead/wheel separation and make for a stiff motorcycle ride.
Over-pumped tires incur wear and tear at an increased rate, contributing to performance loss, traction decrease, and a greatly slimmed-down contact area between the tire and the road.
Overinflation increases the sidewall’s vulnerability when it comes to punctures and blowouts, but we’ll get to that further down on the list—for now, let’s review:
- Over-inflating your tires can elevate the bead from the wheel, causing the bead to slip.
- Monitor your tire’s PSI; never ride on over-inflated tires.
2. Motorcycle Tires Are Below Spec PSI
This is the opposite problem from above, and I’d say the most common cause of a damaged bead seal on a motorcycle.
If your bike’s tires are under-inflated, the lack of tension can cause the seal to slip from the wheel’s rim enough to cause permanent damage.
While the reinforced seal of the bead will activate during a slip with the proper amount of PSI in the tire, if the tire is less inflated than advised, the slip’s distance might be too drastic for the reinforcement to matter.
- An under-inflated motorcycle tire can cause its bead’s seal to fail.
- Keep your bike’s tires at spec PSI to ensure the bead is secured by tire tension and that its metal-stripped reinforcement is snug in place.
3. Improper Tire Installation
Not to pick on home mechanics; unfortunately, this happens at pro shops. Now that you’re becoming aware of the ins and outs of bike tire beads, you’ll know what to look for and what to ask.
An improper tire installation can stop the tire bead from adequately sealing, whether the mechanic used the wrong tools or failed to sufficiently clean the tire’s beads and surfaces and prep the site with proper lubrication.
This is another one of the more common causes of bead failures on a motorcycle on this list. The upside is that motorcycle tire beads are generally built to endure once the tire is mounted correctly.
If you’re unsure of your general motorcycle wheel and tire installation knowledge, it might be good to take the bike to a well-reviewed seasoned pro, ensuring they use the proper tools, sizes, kits, etc.
4. Punctures, Debris, and Road Hazards
Anything that can damage a tire or wheel rim can damage the bead, including sharp metal objects, shattered glass, splintered wood, potholes, curbs, and even torn-up concrete can all put a puncture in your tire severe enough to protrude the bead and stop it from sealing.
It might be as simple as a nail or tack that slipped in, punctured the bead seal, and slipped out unnoticed.
In some cases, riders miss the fact that the bead is failing. They get puncture kits slapped on the tire’s wound and refill them with air only to discover slow leak symptoms they can’t track down.
This can happen in a few different ways:
- It could have been a matter of the bead itself being punctured.
- Maybe the force of the impact dislodged the bead enough to prevent the seal from closing.
- Perhaps while the punctured tire was deflated, the underinflation caused a slip, as mentioned in the section above.
- Either way, once your tire bead fails, patching the puncture in the tire wall or tread won’t be enough to stop a slow leak from airing you out.
5. Ripped Or Torn Tire
It’s pretty widespread moto-knowledge that a ripped tire isn’t a safe bet on a motorcycle; make sure you inspect the bead for rips and tears just and thoroughly as you examine the sidewalls and tread.
If the motorcycle tire is ripped, lack of tension, incorrect position, or airflow in and out could prevent the bead from sealing to the air-tight position required for safe motorcycle riding.
The tear might be too small to notice; as soon as you notice a slow leak on a bike, it’s imperative to track it down.
A slow leak causes chronic deflation, which, as covered above, can cause slips and dislodges that make the leak even worse.
If your bike’s tire doesn’t seal to the wheel, it could be because a slow leak in the tire reduces the PSI enough to affect your motorcycle’s bead.
Or, it could be because the bead itself is leaking…
Maybe we should dedicate a section to just that!
6) Old Age Or Dry-Rot; Reduced Elasticity
If the motorcycle in question was a backyard ornament for extended periods, dry rot could be why your motorcycle tire won’t bead.
Dry rotted tires incur a significant decrease in flexibility, a quality that permeates the tire bead’s ability to seal itself to the bike’s rim.
A dry-rotted tire could also be cracked in a perfect place along the seal to allow air to break through, rendering the bead useless.
In short, if your tires are old and you think you have an air leak, but you haven’t been able to track it down, and if you know for a fact you don’t have a leaking valve stem or a crack in the tire itself, the leaking bead is likely the cause.
This may be because of old age, dry rot, reduced elasticity, etc., but any motorcycle tire with a bead that won’t seal because of a leak shouldn’t be ridden.
A slow leaking bead can lead pretty quickly to a complete blowout, as a deflated tire gets much hotter, much faster.
7) Bent, Damaged, Or Corroded Wheel Rim
If the motorcycle’s wheel rim is corroded, rusted, or busted along the length where the tire beads meet the wheel, the bead will fail, and your tire will lose its air content.
Corrosion is more commonplace on magnesium alloy and die-cast aluminum bike rims. Still, you or your moto-mechanic should inspect the rims of any motorcycle wheel before installing and sealing a new tire and its beads.
Otherwise, your motorcycle tires could fail to bead.
Even the most celebrated and expensive motorcycle wheel on the market can’t seal to a thoroughly corroded rim. As we’ve mentioned a few times, a motorcycle with a leaking tire is unsafe to ride.
In some cases, the wheel is so corroded that air can leak through the corrosion even if the bead does seal.
A similar situation happens when using improper wheel weights results in damage. A bad casting job can cause the rim to leak, but that’s a subject for another article.
The important thing here is that whether your motorcycle tire won’t bead or the rim is leaking, avoid injecting the tire with sealant, or you’ll only be making a mess you have to clean out to replace the tire and/or rim.
Can You Fix a Motorcycle Tire That Won’t Bead?
In some cases, if the tire and rim are both in good condition and the problem was simply that the bead got knocked loose, you can reseat the tire bead and, as a result, reseal it.
If the bike tire’s bead has incurred any damage at all, whether a tiny bend or a large puncture, the whole tire needs to be replaced.
Whether it’s the tire’s internal chords, rubber seals, or whether the beading area of the tire is shredded from the road or rim, a damaged bead can’t be resealed.
When in doubt, we suggest consulting a specialist, as leaking tires are dangerous enough on a four-wheeled vehicle.
On a motorcycle, a blowout could cause injuries or worse.
If you think your motorcycle tire won’t bead, go through this list with a fine-tooth to prevent it from happening again.
Keep in mind that if the tire won’t bead because it’s damaged, the only way to fix the situation is to replace the tire with a new one.