Topic: Mag wheel modification to go tubeless....

[justinmcgiver]

Ok The GS resources site is down and I'm jonesing... The mags on my 79-80 GS1000 have tubes installed. The valve stem hole is too small to accept a standard size valve stem for use on a tubeless setup. I'm considering drilling the stem hole to the right diameter, installing valve stems and going tubeless. Anyone done this? Does anyone see any issues with this?
Here's a pic of the bike in question...

[HavocTurbo]

Get a micrometer and measure the stems you want to use.

Then use a mini right angle drill and a slightly smaller drill bit than the size of the stems.

Check and see if the stem will fit.

IF SO...
Use tire sealant (bead sealant i think... it's black) around the stem and install. Check for leaks.

IF NOT...
Get the next size up drill (still smaller than the stem) and repeat.


My biggest problem in converting mags that had tubes in them wasn't the stem but the mag itself. Finding and sealing all the leaks can be difficult.

Hope that makes sense.

[justinmcgiver]

Thanks for the reply havoc. I'm taking the wheels off to powder coat them so drilling should be relatively simple. Was planing on using bead sealer.
 

My biggest problem in converting mags that had tubes in them wasn't the stem but the mag itself. Finding and sealing all the leaks can be difficult.

Where else were you getting leaks from?

[HavocTurbo]

Depending on the mag and reasons for using a tube....

hairline cracks in them around the outer edges

seen cracks around the "spokes"

also dents, bends, and occasional hole in the centerline ribbing.

[bryanj]

Just seen this, i think it was Kawasaki that had a tubless valve that bolted into the same size hole as a tube valve

[bmarshall]

Try NAPA, they had the smaller size to fit my Yamaha

[MJL]

Depending on the mag and reasons for using a tube....

hairline cracks in them around the outer edges

seen cracks around the "spokes"

also dents, bends, and occasional hole in the centerline ribbing.

Sounds dangerous.

[TwoTired]

The bead lock surface on a tubeless wheel is quite different for a rim designed for tube tires.  It's not just a matter of holding air, its about holding air when the tire sidewall is under stress.

When you are leaned over deeply in a high g turn and you hit a pot hole, it is usually not the time to find out your tire bead seal isn't what it should be.

[kghost]

The bead lock surface on a tubeless wheel is quite different for a rim designed for tube tires.  It's not just a matter of holding air, its about holding air when the tire sidewall is under stress.

When you are leaned over deeply in a high g turn and you hit a pot hole, it is usually not the time to find out your tire bead seal isn't what it should be.

Thanks Lloyd you beat me to it.

As an example....the Honda comstars....some are tubeless some are not...the bead lock on the tubeless is quite different.

[Terry in Australia]

As has been said by the wiser posters here, don't do it. I've got two GS1000's (and "E" and an "S", I'm "Terry" on the GS Resources) and I can tell you that the Suzy mags were never designed for tubeless tires.

Apart from the fact that they're probably porous, like lloyd said, your tires will probably come off the first time you go around a corner fast. (easy to do on a GS1000) Cheers, Terry.

 

[voxonda]

DON'T EVEN THINK ABOUT IT! LIFE IS TO PRECIOUS.

[Tim.]

I think they should start making bullet proof tubes to run in tubeless tires as a backup system.

If my car didn't have run-flat tires, and some sort of puncture-resistant inner tube was on the market, I'd put them on my car for peace of mind.

[ColinMc]

http://www.nuetech.com/

I contacted these guys directly about using the system on street bikes...not approved for that YET...that was 6 months ago I e-mailed them though...so who knows if that's changed.

[HavocTurbo]

As has been said by the wiser posters here, don't do it. I've got two GS1000's (and "E" and an "S", I'm "Terry" on the GS Resources) and I can tell you that the Suzy mags were never designed for tubeless tires.

Apart from the fact that they're probably porous, like lloyd said, your tires will probably come off the first time you go around a corner fast. (easy to do on a GS1000) Cheers, Terry.

 

Aside from the bead edge Terry they will work just fine. Some I have had to put on a lathe and cut others I have not. The biggest problem I have found in converting older mags is the quality of aluminum and the casting/forging methods used.

Most of the really bad rims I have seen were just like sponges. I have no idea how they even lasted with normal stresses.

Not trying to argue with you..... just sharing my experience. And yes, I have had a converted wheel break on me, but never lost a bead seal.... yet.

[Terry in Australia]

As has been said by the wiser posters here, don't do it. I've got two GS1000's (and "E" and an "S", I'm "Terry" on the GS Resources) and I can tell you that the Suzy mags were never designed for tubeless tires.

Apart from the fact that they're probably porous, like lloyd said, your tires will probably come off the first time you go around a corner fast. (easy to do on a GS1000) Cheers, Terry.

 

Aside from the bead edge Terry they will work just fine. Some I have had to put on a lathe and cut others I have not. The biggest problem I have found in converting older mags is the quality of aluminum and the casting/forging methods used.

Most of the really bad rims I have seen were just like sponges. I have no idea how they even lasted with normal stresses.

Not trying to argue with you..... just sharing my experience. And yes, I have had a converted wheel break on me, but never lost a bead seal.... yet.

So you've modified GS1000 mags specifically mate? While I'll always err on the side of caution when trying to help a fellow SOHC-er, if you're saying that you've modified GS1000 Suzuki wheels to safely accept tubeless tires (something that none of the engineers on The GS Resources website has done in the 10 years that I've been a member, that I'm aware of) then I'll bow to your expertise. Cheers, Terry.

[Bodain]

Whats the point? Do I need to tell you how many older  mag wheels I have that don't require tubes, but do require tubes to keep air in them?

[greasy j]

Whats the point? Do I need to tell you how many older  mag wheels I have that don't require tubes, but do require tubes to keep air in them?

same ?

don't see a benefit in doing this. why not have the added safety of the tube? save $ on tubes?

the tu-bliss things are so you can run low pressure on your dirt tires. no reason for that on the street. so again, wot's the point?

[TwoTired]

The tubeless system conversion was driven by two major points, as I see it.
1. Blowout avoidance
2. Less tire heating (allowing higher sustained speeds, and greater longevity at those speeds).

One failure mode for tubes is that the tire carcass becomes damaged and the tube oozes out side the carcass, forming a bubble.  When the tube bubble breaks, you have a "blowout" and the vehicle has a rapid change in stability.  At high speed, the tire will often separate from the rim, leaving the rim to dig into the road surface and catch in ruts and grooves ending in a rollover (cars).
Blowouts on a tubeless system are far more rare, and usually when a tubeless tire fails, the air loss rate is slower giving a transition period of vehicle handling weirdness before going completley flat.  Further, the tubeless bead lock system keeps the tire on the rim far longer than the tube type bead and rim while the wheel is still turning.

I believe the tubeless system was instigated by the auto industry, then adopted by the motorcycle community because the marketing of tubeless was touted as "better" (which it is is some ways).  Tubeless tires do suffer less heating at higher speeds, which is certainly appropriate for high speed motorcycle operation.  If you want to do more than 125 MPH with frequency, then do convert to the tubeless tire/wheel system.

None of this should be construed as an endorsement for tubeless tires on a tube rim without a tube installed.

[754]

Ya gotta ask yourself, do you really feel comfortable at 120mph on a Cheg Shin tube you bought for 11 bux, cause a Conti was 23 bux....

  

 I have never pinched a tubeless tire, in a manner where it would then, not hold air...

[TwoTired]

Ya gotta ask yourself, do you really feel comfortable at 120mph on a Cheg Shin tube you bought for 11 bux, cause a Conti was 23 bux....

  

What, and deprive yourself out of the thrill of cheating death by going as fast as you can with the cheapest parts you can find?
What a kill joy!

There IS that theory of natural selection to consider...   But, if you are under the age of 25, invincibility trumps any real risk, anyway.

I have never pinched a tubeless tire, in a manner where it would then, not hold air...

Just run it low on air and hit a curb or sharp edged pot hole.  Sidewall splits/cracks.
That same scenario is where the tube blisters out of the crack and eventually bursts (in a tube type tire).

[754]

Let me rewrite that.....

 You dont have to worry about pinching a tube.. Ru-Glide it and install with rubber hammer.. This time/hassle saving, might be lost if it does not seat easily..

 Some feel tubeless is easier to repair, by using a plug, easier than re & re ing a tube...

[ColinMc]

the tu-bliss things are so you can run low pressure on your dirt tires. no reason for that on the street. so again, wot's the point?

Actually the Tubliss are also meant for high speed on dirt bikes with FULL pressure in the tires. If you read the description, what it does is hold the bead against the outside edge of the rim, thus elminating the problem of the tire popping off of the bead when you hit a bump at an angle or coner hard with tubed tires without tubes. In their e-mail reply they said they can't confirm what speeds on the street it would be viable for though since they don't have a demand for that. I was informed it works fantastic on bikes running normal pressures in off-roat/dirt environments as well as low pressure situations where it functions sort of like an internal bead lock, but the tire can still shift on the wheel so it's actually BETTER with high pressures as apposed to low pressures. 

Their main issue is making it a DOT legal system because of all the hurdles required to go through for that...

This is what I was informed by e-mail from said company however long ago it was I asked them about it.

[HavocTurbo]

So you've modified GS1000 mags specifically mate? While I'll always err on the side of caution when trying to help a fellow SOHC-er, if you're saying that you've modified GS1000 Suzuki wheels to safely accept tubeless tires (something that none of the engineers on The GS Resources website has done in the 10 years that I've been a member, that I'm aware of) then I'll bow to your expertise. Cheers, Terry.

While it CAN be done.... The biggest hurdles to overcome are metal quality of the day. I have welded and recut all kinds of rims to accept tubless tires. Could they still pop off? How do I really know for sure? Is it safe for everyday riding?

It all depends on your application Terry. If you are racing on them or even riding them to their limits, they will never be better than OEM. That's all I can promise.

But I can also tell you that while I have had a lot of success doing it.... I have also had 5 times the amount of failure. Which is why I always try to make sure the rims I get sent to me are spares or easily trashed if they turn out to be too poor quality metal.

Nothing worse than sticking a 300+ degree wheel on a lathe to cut it and have it start coming off in big chunks.

(I found that if you heat cycle the rims several times and then cut them while still very hot they cut smoother)

Now please don't get me wrong.... I am not saying it is 100% safe to try this... or even have ME do it. But I HAVE done it before..... and it HAS worked. Just not in a manner that will work on every wheel.

Does that even make sense??  Sorry. 

[754]

I am not understanding the heat cycling/.why not just change tool rake angle.

 Low alloy aluminum does cut like crap though, not like t 356.

 havoc are you cutting off the rim & press fitting wider one on, or cutting off the sides and welding to an existing rim?

[HavocTurbo]

Mostly fill welding the rim edge and reshaping.

I've transferred rim edges before and they always turned out poorly.

I heat cycled the rims to facilitate easier cutting. If you place them on the lathe/mill cold the cut line tended to break off in chunks. Kinda like cutting ice.

The older the wheel the more cycles and hotter I get them. Seems to work better even if there is no plausible reason for doing so. I figured it had to do with the quality and porousness of the metal.