From the archive: On the tube

The world has gone tubeless, which can be a hassle for older rims… or maybe not…

Words and Pics: Tim Britton

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When talk turns to tyres the discussion can often get heated – what one rider swears by another may swear at – and it is even more complicated when tubed or tubeless is chucked into the mix. For classic and twinshock riders, certainly in the trials world, remaining on tubed tyres is limited to IRC really.

One of the problems is that a tubeless tyre doesn’t always stay on a tubeless rim, there being a slight difference in the tyre well which prevents it seating properly. However there are those who use tubeless tyres quite happily on a tubed rim – including one recent winner of the Pre-65 Scottish – and claim no problems.

Take one tube type rimmed wheel and add a tubeless tyre with a TUBliss system.

The easy answer is to change rims to tubeless type and the problem goes away. Okay it’s replaced by another problem – which tyre to choose.

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Mind you that can become expensive if you’ve several bikes to deal with and it also means any originality is lost.

There are no really fancy items needed for fitting the TUBliss system, if you’re someone who changes your own tyres then it’s likely you will have such kit to hand.

Originality doesn’t always matter in the competition world but it is nice to keep a bike looking correct if you can.

One option is to fill the rim with loads of security bolts but that can add a load of weight as well as make balancing the wheel an interesting challenge.

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Included in the kit are comprehensive instructions. Read them and understand them, we don’t care how many tyres you’ve changed, these instructions are important.

There is another option, the TUBliss system and CDB got hold of one to try it out – Michelin also kindly supplied a tubeless X11.

There’s a security bolt hole to drill in the rim. Yes, we know you will have other holes for other bolts and there are plugs available for them as this one has to be in the right place.

The concept of the system is quite simple and is effectively a two-chamber idea with the well where the rim tape would be, filled with a small diameter tube at extremely high pressure which holds the tyre bead against the rim and could be regarded as a 360 degree rim lock.

Once the hole is drilled and the old ones plugged, the rim tape must be fitted. Take care it doesn’t overlap and is sticking to the rim on the inside as this is an important sealing point.

Once that is in place then the tyre can be filled with air to whatever pressure is required within the recommended 0-10psi range.

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There needs to be a hole through the tape for the one security bolt – supplied in the kit – to go through. This is chopped with a steel drift and a smart tap with a hammer.

A special security bolt or rim lock, depending on where you live, is supplied with the system and this prevents the tube from moving around.

Slip the high pressure chamber onto the rim, use plenty of soapy water. There are tyre fitting pastes and goo, but the instructions say soapy water rather than a proprietary paste.

Fitting the TUBliss system is a little different to the way a normal tyre and tube would be fitted and the company supply detailed instructions to aid fitting but if you can fit ordinary tyres you shouldn’t have any difficulty fitting this system.

Make sure the high pressure chamber is seated properly and in the correct place, again this is an important part of the sealing process. Our man eased it in place with a tyre lever.

As you can see we’ve fitted this to a trials bike, but the blurb with the kit and the website all show MX or enduro machines with the TUBliss system in place.

Once the high pressure chamber is in, lube the tyre and rim with soapy water, then slip the whole lot inside the tyre, yes different to normal but that’s what the instructions say.

Our thanks go to Mick Grant for actually doing the job…

Once inside the tyre then fit each bead to the rim as per normal, use plenty of lube and the job should be quite easy. Be careful not to catch the high pressure chamber.
Once the tyre is in place check the bead is in the right place and you’re clear to go to the next stage which is popping it up on the rim… more lube needed.
Yes, that does say 110psi and this isn’t going to happen with a foot pump, a compressor is needed here. Once the hose comes off the pressure will drop to the recommended 100psi.
With the high pressure chamber filled, blow up the main tyre, wipe everything clean and allow yourself a satisfied smile…thanks Mick!

Why do it?

It is relatively easy to change rims from tube type to tubeless type, all it takes is money and then any number of tubeless options are available in tyres.

But what if the rims on the bike are okay or you want to keep them for aesthetic reasons but still have tyre choice? Well this could be an option for you.

Difficulty 3/5

Resources
A bike stand so the rear wheel can be removed, tools to suit your rear wheel removal needs, tyre levers, soapy water, a compressor to push 100psi into a tube.

Supplier

TUBliss

Contact them through nuetech.com where there are details of suppliers worldwide.michelin tyres

See your local dealer.

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