Tubed rear tyre on hardtail (safety question)

[Bhud]

Any thoughts on whether it's generally safe to stick a tubed rear tyre type on a hardtail, if you plan to run lower pressures than normal on the rear?

The carcases and beading(?) surfaces on tubeless types are very hard, and they seal and stick strongly to the wheel when the tyre is inflated. Tubed tyre types are softer, and they don't grab onto the rim as securely when they form a bead.

My wheel will have a tube in it because I'm just tired of rim leaks. However, I'm considering whether to go for a TL type (with an additional tube inside) or a TT tyre. The bike will be capable of speeds up to about 110-115mph, not that it's the sort of thing on which you would want to bomb around. The main advantage I can see with TT tyres is that they're much easier to fit. Ideally, I'd like to go with a TT tyre and run lower pressures, but I won't do that if it's unsafe.

[Easy-X]

I stumbled into this topic a bit from restoring the old DT. The way dirt-bikes get round it is with a rim lock that clamps the tyre to the rim from the inside.

What's the rim size (diameter and width) on this bike of yours?
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Bhud]

Rim locks, eh. Sounds interesting - I'd never heard of them.

The tyre size is 130/90-16.

[pepperami]

[stinkwheel]

I'd suspect more hard-tails have tubed tyres than don't, given they are usually of the custom type and have spoked wheels. Hell, it's not totally unheard of for people to run car tyres with a tube in on a hardtail. Big 4" avon safety mileage are probably the most common tyre fitted to a hardtail and they are tubeless fitment.

Fitting a tube in a tubeless tyre is fine. My MZ street moto had this as standard and it was TUV and type approved (for those specific, named, tubeless tyres, some of which were proper sportsbike tyres). I used to run them on my 350 powervalve too because the rims were in a shit state and wouldn't hold air properly.

The main issue with tubed tyres is if they are running at excessively low pressure and the tyre slips round on the rim, this can rip the valve off and cause an explosive deflation. Yes, trials guys use rim locks to prevent this but I'd worry about how this would affect balance at three figure speeds. That said, they run with barely any air in at all.

Another option would be to fit tubeless and slime them.

What sort of pressures are you running at anyway? Maybe you could up the profile and run a higher pressure so you get more sidewall flex to soak up the bumps?

I'll add that fitting rim locks takes the "easier to fit" thing and throws it out of the window.
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[martin734]

Didn't all the H-D hardtails have tubes on their spoked wheels?
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Current bike: ST1100 "Big Red"

[Easy-X]

This sort of thing:

https://www.dirtbikexpress.co.uk/images/products/10638_l.jpg

However you're talking about road bike tyres >5" and similarly wide rims.

AFAIK the main issue with tubed tyres is throwing lots of torque at them - what you'd expect a lot of for offroad stuff - and the wheel rim literally spinning within the tyre. If this is a hard tail road bike I don't suppose you're expecting to do burnouts with it
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Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[Bhud]

Thanks for the info guys. That's really helpful.

Yes, I was thinking of going the TT tyre route just so have an easier time of tyre fitting. However, I had my doubts about the safety of TT tyres in this application (I intend to run about 18 to 20 psi). As was rightly pointed out, the Harleys and whatnot of yesteryear all had tubed tyres, probably because of spokes and a desire to make it possible to change tyres at the roadside. However, the centripetal force exerted on the sidewall when cornering (it's a modified "universal" type Japanese frame) make it a safety-critical issue. The motocross rim lockers are a nice idea and would probably work, but as they're new to me I think I'll pass on that this time.

I'm not gonna risk it. It will have a TL tyre with a tube inside it. That's settled then, and thanks again.

[Sister Sledge]

Although not that powerful, I run the 404 with a tubeless tyre and inner tube fitted because it's a spoked wheels bike. The rear tyre usually sits at quite a low pressure of 17psi cold too. (I run it at that pressure following advice from other CCM owners in another group)
My bike does not have rimlocks and I rode around 4K miles this year without a single issue.

You might want to consider actual tyre temperature rises if you run an inner tube inside a tubeless tyre. I've read somewhere that tyre designs mean that the combination I use will see hotter tyre temperatures. Again though I've had no problems. Saying that, my rides tend to be 150 to 200 miles maximum.
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CCM 404 DS

[stinkwheel]

[Grubscrew]

It’s worth mentioning that you can also use a bead sealer, it’s like a black rubber liquid, which when put on the bead and bead rim it adheres to both, and stops slippage. I use it on a machine of mine which is a high torque unit and the tyres are still in the same place after years of use.
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FJR1300/CBR1000F