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Discussion Starter #1
Just curious if anyone out there has any experience running spoke wheels tubeless. Methods used would be nice. Maybe it's a dumb idea for a street bike?
 

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Only on the rear of Trials bikes :I

One big advantage is that you can dispose of rim locks, which are both weighty and troublesome.
Variations on the tubeless rim design have evolved away from through holes, because they require a big fat rubber seal over the spoke nipples, which is both weighty and troublesome.
 

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Keep in mind tubeless and tube wheels have a different profile of the bead area. Likewise with the tire bead being different. My Kimtabs are a tube type wheel that I converted to tubeless. It doesn't seem to want to hold air after sitting awhile. I think I may have to put a tube back in.
 

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Discussion Starter #4
I've seen some supermoto guys using some fancy silicone caulking combined with gorilla tape. I can't imagine it's heavier than a tube.
 

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Discussion Starter #5
I'm definitely more worried about the rim profile not holding the bead to the rim. So far in my experience mounting a tubeless tire with a tube was far more difficult not only to mount but to remove the tire as well. I just can't imagine one easily breaking a bead and tearing loose from the rim. I also have no experience with giving it a shot either so I'm proceeding with caution.
 

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You can't run tubeless tires on a tube type rim, not without taking a razor blade to the bead first anyway. You'll probably never get the tire to completely seat in at least one spot.
Tube tires on a tubeless rim will flop loose around on there and never hold air.

It's the rim lock or rim locks that weigh a lot and impose an imbalance on the wheel and rust and make it a pain to change tires and bottom out the rim if you happen to hit the tire hard where they are.
Some will tell you to just use sheet metal screws drilled through the rim instead, if you are into cheap and dirty fixes that might work.

I ride a one ply radial tubeless on one of my bikes, it's one ply because it can be made almost a full pound lighter then a two ply version of the same tire.
 

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There are, of course, tubeless-type wire-spoke rims. The majority of the aftermarket ones are mainly for choppers, and have some super-exotic spoke setups. But the OEM ones have a tall center flange, which the spokes hook through, and nipples located the hub. The three I bikes I know of that come (came) with this type of setup are the Honda CMX450C Rebel, the V-Strom 650 (I think just the XT adventure version?), and the Yamaha 225 Serow (back wheel only).

Honda CMX 450 Rebel.jpg
web-wheelKWP_3182.jpg
2012-03-02113620.jpg
 

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Discussion Starter #8
You can't run tubeless tires on a tube type rim, not without taking a razor blade to the bead first anyway. You'll probably never get the tire to completely seat in at least one spot.
Tube tires on a tubeless rim will flop loose around on there and never hold air.

It's the rim lock or rim locks that weigh a lot and impose an imbalance on the wheel and rust and make it a pain to change tires and bottom out the rim if you happen to hit the tire hard where they are.
Some will tell you to just use sheet metal screws drilled through the rim instead, if you are into cheap and dirty fixes that might work.

I ride a one ply radial tubeless on one of my bikes, it's one ply because it can be made almost a full pound lighter then a two ply version of the same tire.
I think there are quite a few people that would argue otherwise about a tubeless tire on a tube rim. Myself included. It can be a beast to seat right, but it's doable and I have yet to need a razorblade. Not trying to argue, just curious why you think it can't be done?
 

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I think there are quite a few people that would argue otherwise about a tubeless tire on a tube rim. Myself included. It can be a beast to seat right, but it's doable and I have yet to need a razorblade. Not trying to argue, just curious why you think it can't be done?

I used to get cast off soft compound tubeless trials tires from the modern riders and try to use them up on my vintage trials bikes. Yes you can stretch them on and you can also damage them while doing it, I never had the balls to take a 2 ply radial much over 100psi when I was mounting them, I didn't want to loose an appendage, so I trimmed the rubber. ymmv

Lots of guys did the same, you could often see them running with a big wobble in the tread.
not a big deal at 15 mph, not so good at 100mph

It is a beast to seat because it is the wrong size for the wire that is embedded in the tire bead. :rolleyes: How many wire strands did you break in yours when you put it on too big of a rim?
Did you still mount a rim lock and how did that work out for you? or did you need one with the tire on that tight? Did you use a bias or radial type tube? Ever sheered off a valve stem, I have :( it sucks, you can't patch a sheered off valve stem. :eek: so many ways to screw up when you mix and match, and ultimately, you are probably trying to mount tires that are so much better then the original ones, now your bike is going to start to exhibit all of it's other weaknesses.

I say go for it, but you'll wish you had them on tubeless type aluminum rims by the time you get them mounted anyway.
 

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lol some times your nipples are in the middle of the spokes, which sounds like a scary place to put your nipples, but it works.

 

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Discussion Starter #11
If you put a strap on the outer diameter of the tire before airing up it helps seat the bead. It also requires a fair amount of lube.
 

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If you put a strap on the outer diameter of the tire before airing up it helps seat the bead. It also requires a fair amount of lube.
That would be for mounting tubeless tires without a tube.

… if you have new tires that have been squished in transit, you can also put a tube inside it and pump it up real big, then leave it in there over-night, that stretches the sidewalls outwards and makes it mount super easy.
 

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Discussion Starter #15
There's a gazillion ways to seal spoke rims to run tubeless tyres. Just google it.

Oh, hang on.....

https://www.google.com.au/?gws_rd=ssl#q=sealing+spoked+motorcycle+rims
The problem with most searches is that they are for either wider rim adventure bikes or motards. The rim profile is far different from say an 18x2.15 or 18x2.5 WM profile, or at least that's what I see. I guess I should have specified what the intended size would be. I also ask here because safety is often the first concern here, where other forums tend to encourage idiocy.
 

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You need to ask yourself, how important are the bumps and the flat spots.
You know it's the rim design that helps keep a tubeless tire on the rim when it goes flat, you know a tube rim has a sloped bead contact area leaning towards the centre of the rim.



Do you care if your tubeless tires perform as designed when they are not mounted on the proper rim, and might it result in a catastrophic accident at the speed you could experience a flat tire at ?
 

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Discussion Starter #17
You need to ask yourself, how important are the bumps and the flat spots.
You know it's the rim design that helps keep a tubeless tire on the rim when it goes flat, you know a tube rim has a sloped bead contact area leaning towards the centre of the rim.

Do you care if your tubeless tires perform as designed when they are not mounted on the proper rim, and might it result in a catastrophic accident at the speed you could experience a flat tire at ?
As I understand it the tubeless tire will release pressure at a slower rate than that of a tubed wheel with a typical "nail" hole scenario. Obviously that doesn't mean much if you tear a huge chunk out of the tire or heavily dent the rim, but how often do those things happen, and will it matter which type in such an extreme scenario anyway? I'd venture to guess neither option would fare well, and something of that nature will probably cause an accident regardless.

I did find a thread that mentions the profile rib you point out not being on a larger 21" diameter rim, but usually the smaller diameter rear. Most of the motard threads don't have that rib at all, but they also have a considerable width between the lip of the rim and the nipple valley.
 

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I probably wouldn't bother / risk trying to seal up the nipples on a skinny 2 inch rim - just use a tube in a tubeless tyre and call it good.
 

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Some good stuff to be found in the link above.

For what its worth the vast majority of tyres used in classic racing are tubeless type tyres fitted to tube type rims. The main advantage of running a tubeless rim (usually cast wheel) is the safety provided by the inner tyre guide or rail which keeps the tyre on the rim in the event of a sudden flat.

However many early cast alloy or magnesium rims; Campag, Dymag, CMA, Morris, Marvic Streamlines etc do not have the inner rail, the rim profile is just like a tube type rim and yet take a walk around the classic race paddock and most are running tubeless tyres without tubes on old cast wheels, TZ750s, RG500s you name it. I do the same myself. The ACU don't see it as a safety issue, if it was these bikes wouldn't get through technical inspection.

As for running spoke wheels without tubes? Well I have done it and have not had a problem. This is how to do it; I always start with a new alloy rim which is light grit blasted on the outside or rather area covered by the tyre, the wheel is built as normal, the nipple dimples and surrounding area is cleaned with a solvent and then filled with a hard setting silicone sealer which is pushed into the depression with your thumb as it goes off, the silicon should be convex like a blister and 3/4 round, the silicone underneath will take a couple of hours to go off fully so get a tyre on as soon as possible and pump up to pressure this will push the silicon into the back of the nipple = Done, if you do it correctly you will have a tubeless spoked wheel.

Don't bother with steel rims.

Next question I guess is this, have I ever had a failure? No. But I have ripped valves out of inner tubes on road bikes with proper HP. This was so frequent that in fact we used to drill the side of rims say 5 or 6 each side of the rim equal distant and screw self tapping screws through the rim and into the tyres to grip the tyres. Often I still see original bikes with the holes still there especially on early RG500, TZ750 and racing Z900 and the like.
 
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