Is it possible to field install a tire on a modular wheel?

[BenFenner]

I saw something on TV the other day that may have solved a problem of mine. I'm planning on purchasing some expensive modular wheels in the future and I'm always wary of what could happen to them at the tire mounting place.

After seeing a shop have to replace a Humvee H1 tire it seemed like the same could be done with any modular wheel. I know this isn't exactly on topic, but I trust you folks so here we are.

Any reason this wouldn't work? (Skip to 6:07)

http://youtu.be/i64Jpft86FM?t=6m07s

[mcoupemindy]

The answer is no.

First, that's steel. Remember that all expensive automotive 3pc wheels are aluminum and are easily bent.

Second, modular wheels use bolts not studs and nuts to hold the inner and outer together. Your compression area would be longer than the face is thick and you couldn't tighten it. Also factor in that these bolts are only tightened to 13-15 ft.lb. and that wouldn't be enough force to clamp the tire.

Third, there would be no way to seal it from leaking. To get a good seal on 3pc wheels, you have to use a thick liquid sealant applied to the void between the two halves.

[BenFenner]

I'm aware of the aluminum, not sure how that causes an issue?

I was assuming the thick liquid sealant applied to the void would be done at the same time as the tire install.

I don't see how bolts + nuts would be any different than the studs + nuts unless you're saying the bolts won't be long enough?
You could always use long bolts for the initial job and switch to the correct shorter bolts (one by one) once the wheel sealant has dried. No?

I'm not sure what you mean about enough force to clamp the tire? The wheel doesn't have to clamp the tire (forget the Hummer for now). Once you get it on there, you use an air compressor to seat the bead (if you haven't gotten that far already) and then you're home. No?

Have I covered all your bases?

[mcoupemindy]

I'm aware of the aluminum, not sure how that causes an issue?

I don't see how bolts + nuts would be any different than the studs + nuts unless you're saying the bolts won't be long enough?

I'm not sure what you mean about enough force to clamp the tire? The wheel doesn't have to clamp the tire (forget the Hummer for now). Once you get it on there, you use an air compressor to seat the bead (if you haven't gotten that far already) and then you're home. No?

I was assuming the thick liquid sealant applied to the void would be done at the same time as the tire install.

Have I covered all your bases?

Ben, not being a jerk, but have you rebuilt modular wheels before? If not, you'll understand why on most of this the first time you do.

I'm aware of the aluminum, not sure how that causes an issue?

Aluminum is very soft. Any small mistake will result in a visible blemish. Additionally you will have 40+ bolts to tighten at the exact same time and shouldn't load one more than another. Note, this applies to face drilled wheels, not through bolt. Through bolt may not have this issue.

I don't see how bolts + nuts would be any different than the studs + nuts unless you're saying the bolts won't be long enough?

That's correct. Bolts will be too short considering that the longest that go into 3pc wheels are 12-14mm long.

I'm not sure what you mean about enough force to clamp the tire? The wheel doesn't have to clamp the tire (forget the Hummer for now). Once you get it on there, you use an air compressor to seat the bead (if you haven't gotten that far already) and then you're home. No?

A proper (square) fitting tire retains a good bit of pressure on the bead.

I was assuming the thick liquid sealant applied to the void would be done at the same time as the tire install.

Nope, it needs to cure BEFORE putting the tires on. The correct sealant takes 72 hours to fully cure as it's a sticky glue.

If you're going to spend serious dime for wheels, then you can also afford to take them to a shop with the proper equipment to mount the tires without damage.

[BenFenner]

No, I haven't re-built a modular wheel yet. No offense taken.

Visual blemishes on the inside of the inner barrel wouldn't bother me, same goes for anywhere the tire covers. If I keep the faces down during install and be careful with the tool used on the showing hardware I should be okay?

You don't have to tighten all of the bolts down at the same time do you? You can't do an elaborate star pattern while tightening only little bits at a time? Same idea when tightening camshaft caps?

Can you describe face drilled wheels versus through-hole to me?

A proper (square) fitting tire retains a good bit of pressure on the bead.

Understood, but I'm still not seeing how assembling the wheel with the tire on causes any issues here? Once the hardware is tight and the sealant left to cure, you could then seat the bead and fill and be on your way?

I didn't know the sealant took 72 hours to cure. Could you not leave the tire on the wheel for those 72 hours (likely unseated) and wedge open the tire a bit to allow air flow for curing? Maybe keep the valve stem open too?

[BMWBergy]

Ben, not being a jerk, but have you rebuilt modular wheels before? If not, you'll understand why on most of this the first time you do.

I'm aware of the aluminum, not sure how that causes an issue?

Aluminum is very soft. Any small mistake will result in a visible blemish. Additionally you will have 40+ bolts to tighten at the exact same time and shouldn't load one more than another. Note, this applies to face drilled wheels, not through bolt. Through bolt may not have this issue.

I don't see how bolts + nuts would be any different than the studs + nuts unless you're saying the bolts won't be long enough?

That's correct. Bolts will be too short considering that the longest that go into 3pc wheels are 12-14mm long.

I'm not sure what you mean about enough force to clamp the tire? The wheel doesn't have to clamp the tire (forget the Hummer for now). Once you get it on there, you use an air compressor to seat the bead (if you haven't gotten that far already) and then you're home. No?

A proper (square) fitting tire retains a good bit of pressure on the bead.

I was assuming the thick liquid sealant applied to the void would be done at the same time as the tire install.

Nope, it needs to cure BEFORE putting the tires on. The correct sealant takes 72 hours to fully cure as it's a sticky glue.

If you're going to spend serious dime for wheels, then you can also afford to take them to a shop with the proper equipment to mount the tires without damage.

+1. I can vouch for all of this, as I'm busy building two sets of wheels presently...

[kojohns]

If you're going to spend serious dime for wheels, then you can also afford to take them to a shop with the proper equipment to mount the tires without damage.

Can you point out what proper equipment would be? So someone can walk into a shop and right away say 'not good enough' by looking at the machine?

[BenFenner]

If you're going to spend serious dime for wheels, then you can also afford to take them to a shop with the proper equipment to mount the tires without damage.

I actually don't have too many issues with the machine that puts the tire on the wheel. My main concern is the tire de-mounter which looks like it it ready to crush the wheel every time I see those inattentive operators working it.

Hmmm, maybe I only need to worry about removing the tires once spent and not the installation...


When I called around town after my previous wheel purchase I asked if the shop had any issues working with lightweight, aluminum, racing wheels. I got turned down by 5+ shops until I found the one in town that said it would be no problem. They do good work, have a touch-less tire installation machine, didn't seem phased when I told them they'd have to reverse-mount the tires on the rear Roadstars when I had some punctures repaired, and haven't done me wrong yet. However they have a posting in the lobby about how they are not responsible for damage to wheels, etc.

No wonder they have no issues working with expensive/rare/fragile wheels... =/

Can you point out what proper equipment would be? So someone can walk into a shop and right away say 'not good enough' by looking at the machine?

Most common is the Hunter Touchless tire mounting machine. Model numbers... Don't ask me.

For reference, I've done a couple tire mount and balance jobs myself at a shop my buddy worked for so I'm familiar with the machines and process. I've also been present when a touchless tire mounting setup bent a steel wheel when used by an inexperience operator. It didn't help that it was one of my wheels.

[f50nut]

Even if you could do it without damaging the wheel, the sealant has thickness. If you wait to torque the wheel down after it cures, you not only risk leaks, but the wheel may not be true. And good luck properly applying a bead of sealant with a tire flopping around on the halves.

The only tire shop in my area that had a touchless machine is Mavis and they did a great job.

A properly built, high quality 3-piece wheel should balance very well with minimal weights added. Do it right.

I actually don't have too many issues with the machine that puts the tire on the wheel. My main concern is the tire de-mounter which looks like it it ready to crush the wheel every time I see those inattentive operators working it.

Hmmm, maybe I only need to worry about removing the tires once spent and not the installation...

Removing the tires by splitting the wheel may be possible, but it sounds like a huge waste of time. Every wheel that I've split was a pain in the ass. None of them just fell apart after removing the bolts. The sealant needs to be cut out of the channel on both halves. Even after that the center bore of the halves still put pressure on the wheel center.

[BenFenner]

I don't think I'm explaining myself well enough? Obviously the hardware would be fully torqued before the sealant is allowed to cure.

I'm thinking the hardest obstacle right now to overcome would be getting the first tire bead seated on the inner barrel far enough to allow the short hardware to reach. If looong hardware is used it could solve a lot of problems but then you have to worry if the tire bead is strong enough to warp either barrel as you slowly torque the whole thing together. And maybe you'd do unacceptable damage to the mounting faces of the wheel having to use excessive torque and TONS of turns to bring everything together.


What exactly is "doing it right"? Finding a shop with a touchless machine that works on non-OEM wheels (Walmart and such won't do anything aftermarket, likely because they retain liability) that doesn't make you waive their liability if they damage your wheel?
I have not been able to find such a place.

[f50nut]

You're trying to assemble a wheel around a tire, but there's no way to seal the wheel with a tire on, and you can't apply the sealant before putting the wheel together at least partially.

[hexagone]

Yes you can, but not for 99.5% of modular wheels.

The "flat-base" 13"-15" BBS motorsport wheels allowed for wheels to be assembled and tires mounted on your own.

See here:

http://www.bbs-racing-wheels.com/sei....txt/flatb.htm

[BenFenner]

That's a great link hexagone. I learned a good bit there about why wheels are shaped the way they are.

It seems to me (just looking at the wheels in profile) that the method used for the flatbase style could be used for the drop-center wheel with no issues. Only that it is a cumbersome method so you don't have to do it. What am I missing here?

[hexagone]

That's a great link hexagone. I learned a good bit there about why wheels are shaped the way they are.

It seems to me (just looking at the wheels in profile) that the method used for the flatbase style could be used for the drop-center wheel with no issues. Only that it is a cumbersome method so you don't have to do it. What am I missing here?

Also remember- Flat base and other motorsport wheels use 'sealing rings' instead of a silicone-based sealant. These rings are usually just a large flat ring with grooves cut out where a big rubber ring sits as a gasket. So these can be inserted with the tire around an inner or outer half.

[BenFenner]

That o-ring (same as on the Hummer) may be what makes all the difference. =/

[MrTorque]

I hesitate to suggest it but what about a visit to a high end car dealer? I've had my local Mazda dealer do my wifes' RX-8 and they did no damage. They also charged less then the tire shops I called for quotes and to see if the could mount 35 series tires. If there aren't any BMW dealers close what about a Chevy dealer that has alot of 'Vettes? Modern tire machines will work fine if used by the right personal!

[Wertles]

I now only have my wheel refinisher change tires for me. He knows how wheels are damaged, what it takes to fix them and how to change a tire (and balance properly) without a scratch. He has a bin full of clean towels to pad and protect everything. Quite a difference watching him do it as compared to the local chain store.

[f50nut]

That o-ring (same as on the Hummer) may be what makes all the difference. =/

Current cost for a new gasket for the BBS e88 is $45 each, so add $190 to your tire cost. You're right up there with the cost of mounting and balancing at a tire shop.

[BenFenner]

This is not to avoid paying a tire shop to have them done.

Good idea with the wheel refinisher Wertles. Thanks.

[f50nut]

This is not to avoid paying a tire shop to have them done.

If you could do it, would you be field-balancing them too?

[BenFenner]

No, I've seen and performed the balancing procedure on the proper machine and there's so little chance of doing real damage to the wheel (assuming sticky weights) I have no issues with a shop performing that task.

One option for me may be to encourage my independent shop buddies to finally get their own tire mounting machine so I can do it myself. Maybe go in on it with them. I'm exploring all options.

[coupe du jour]

http://www.hunter.com/tirechanger/tcx575/

Find yourself a shop with one of these, slip the guy running it a few papers for good measure, and you're golden.