Tubeless Conversion Index Page

Thinking of using these OE TL rims for your conversion?
Be aware that on these rims spoke nipples are in the hub, not the rim.
You’ll need to convert the whole wheel to fit your forks / discs / spacers and so on.
Suddenly it’s all a bit complicated.

Many flagship travel bikes run ‘adventure-look’ spoked wheels, but OEM spoked + tubeless is only slowly catching on. Usually, they’re non-Japanese premium brands like BMW, Triumph or KTM. I update a list here.

The original one-litre Africa Twin and Yamaha’s XT700 were two bikes where you‘d have expected tubeless. The 2020 1100cc AT now features tubeless (right). Front 21-inch wheels seem to be a problem, but it must well be a cost thing too. Spoked tubeless fronts in 19″ are much more common, even on Jap travel bikes.
These days manufacturers use spoked wheels on adv bikes as a signifier of ‘off-road adventure’, as well as the perception of being repairable, lighter, stronger, more shock absorbent and cool. Meanwhile tubeless is just plain safer and infinitely easier to repair flats. On a CRF450R motocrosser running rim locks at 10psi, a tube is probably a better idea and the van’s nearby. On a quarter-ton Adv battleship halfway down Ruta 40, getting a flat is a pain.

OEM spoked tubeless wheels

Making a spoked tubeless wheel rim is expensive but it”s been done for years, right back to the mid-1980s Honda XL600M (left), and almost certainly before that.

Recent bikes that come with them stock include the BMW 1200GSA, the original Aprilia Caponord (below), Suzuki V-Stroms, Yamaha XT1200Z, KTM V-twins, some Triumph Tigers and Explorers (top of the page) and now 1200 Scramblers. Even Honda’s oddball X-ADV scooter (right) has small spoked TL wheels. 

The picture below of a 2005 Caponord shows the main ways of designing a spoked tubeless rim. On the rear: spokes hook to ‘outboard’ flanges on the rim. The front uses a less well triangulated single ‘inboard flange’; V-Stroms (left) have paired inboard flanges up front. Note that the nipples (spokes tension adjustment) are at the hub, behind the rotors.

BMWs, including the 850GS twin  (below), run 40 straight-pull spokes directly into the protruding rim edge – there is no flange. I’ve noticed this relatively exposed edge can get scuffed about from stony terrain, although it would take a lot to damage the spoke mounts.

Such wheels can be heavier than same-sized cast wheels. Weight is saved by not using inner tubes, but the additional unsprung weight on any wheel is the last place you want it. It takes more force to get that mass turning, more braking to slow it and better suspension to control it.

Trials Tubeless

You could try and track down tubeless trials bike rims, but they’re usually 32 spoke. They do it two ways: one is the usual inboard flange with hub-end nipples, as below left. The other is a flat well with a groove to either side (below right) which lets a thick, tight rubber rim band slot into place and help and seal off the spokes – a sort of much simplified Tubliss system.

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You do wonder if this trials rim band plus some sort of added adhesive might work on a regular rim (with lips but without the side grooves). It sure would be a simple way of doing it but clearly, a flat well is best. I think Morad does rims like this in 36 x 18.
A 2017 KTM 1090 Adventure (left) has a similar system: a regular 21-inch Akront rim but with a band rather crudely vulcanised or otherwise glued into the well.

Most road bikes run 36 spokes or more. DID 36-hole TL rims do or did exist, but so far only in pictures or cruddy, corroded used ones on ebay. When changing the spoked rim you’re constrained by the number of spoke holes in the stock hub because changing a hub is a much bigger faff. Fitting a new rim is dead easy. Missing out a few spokes to make a standard 36-spoke hub use a 32-spoke trials rim is a bodge too far, even for me.

Branded or otherwise, it’s hard to find less expensive spoked TL rims off the shelf. The only ones I’ve seen are in China: Risun (Risen?) outboard tubeless rims in 17 or 18 inches only (left) and just $60 a shot. Problem is, you have to order a minimum of 200 units. And there is still the hub-nipple problem.
Especially with 21-inchers, finding an OEM TL rim is difficult or expensive. With 21s you may be better off buying a safety lipped rim (also rare) and sealing it by hand or using the processes described here.

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