Update Spring 2016. See bottom of the page
Tubeless tyres are a Good Thing. Having run them on my desert cars, the ease of quickly plugging punctures is an Even Better Thing, even if this practice is considered a ‘get you home’ measure and even outlawed in some places. All cars and most modern road bikes run tubeless tyres. To me running tubeless presents major advantages for overland travel too.
- Easier: punctures are very easily repaired
- Safer: punctures deflate slowly and controllably (unlike a tube bursting and collapsing)
- Lighter: less unsprung weight (more relevant to racers)
- No need to carry bulky tubes, but should you have a problem, one can be fitted
- Many tubed rims have the requisite safety lip (see below), though not always on both wheels (as I found on my Tenere, pictured above)
Originally written in 2008 – updated with added details on GS500R in 2012 – and again in 2015 and again in 2016
A tubeless HUBB discussion from 2012
Cyb’s version of the DIY procedure described below (good photos and Mounting Tubliss liners to my GS500R
Update 2015: trying out BARTubeless sealed rims on my CB500X. More here.
Update 2016: Japanese Outex tape and glass sealant DIY – see bottom of the page
See this short discussion too
If you can’t do a roadside repair chances are your tyre is well and truly buggered. I’ve had trips where I’ve crossed borders on flat tyres for want of an unobtainable tube. With tubeless all I need is a pump and a handful of plugs, widely used in the developing countries which after all, comprise the Adventure Motorcycling Zone.
My 2008 XT660Z had spoked rims and tubed tyres so I asked on Horizons if sealing the well of the rim (where the spokes come through and where air would slowly leak out) was a good idea. The discussion concluded it was do-able and had been done. I like to experiment with new ways of doing things, so I went ahead.
Is it safe?
Some Flat Earth-like individuals who contribute frequently to online motorcycle forums vehemently proclaim that sealing a spoked rim to run tubeless can’t be done. The fact that they are clearly wrong doesn’t help shake this belief.
I’ve yet to read any direct experience, even second or third hand, but some nevertheless claim it’s lethal. When actual reasons are given, the possibility of a tyre coming off the rim at high speed is cited (or perhaps the sealant unpeeling). But were that possible, how is it different from a tubed blow-out in the same circumstances?
It isn’t. The difference is a tubeless tyre deflates very slowly, because the air can only escape around the [typical] nail pushed through the tyre carcass (or even more slowly through poorly sealed spoke nipples or a bad rim seal). When the same happens to an inner tube, pressure is lost almost instantly as the tube collapses with supposedly dangerous consequences. Sounds lethal and bikes being bikes I’m sure it can be, but in all my years of tubed riding I’ve never crashed a bike as a result of a tube puncture (others have).
It’s also possible the DIY element puts some off, but to me DIY has always been a part of what’s now called adventure motorcycling, long before you could outfit an overland bike from an online calalogue.
Think about it. What’s the worst that can happen, compared to an inner tube blowing out on a 100mph bend? After a DIY conversion you may get an annoying slow leak from an imperfect seal which if unmonitored, may lead to pressures dropping low enough to cause rim damage on a rocky trail or a highway pothole. And when the rim gets dinged you lose the tubeless seal until that dent is knocked back out. I know because this all happened to me following my DIY conversion in the Tenere (see below).
Meddling with tyres is understandably seen as a risky practice, but how many of us have ridden long highway miles on ‘road-legal’ knobblies like Michelin Deserts or MT21s and have actually felt safe on fast, busy, wet roads? It’s not something I like to do anymore, but I suspect emergency braking on such tyres could have much more lethal consequences than sealing spoked rims to run tubeless tyres.
Of course the best solution would be to have an OE spoked tubeless set up, as found on expensive BMWs, KTMs and Caponords, but we haven’t got there yet so some of the current alternatives are given below.
As the adventure motorcycling trend evolves, more and more flagship models are running ‘adventuresome’ spoked wheels designed to run tubeless. They include BMW GS12s, Aprilla Caponords, KTM V-twins, Triumph Tiger and Explorers (left), as well as the old Honda XLMs from the 1980s (see below). This picture of a 2005 Caponard shows the two ways of doing it: on the rear it has BMW-style ‘outboard’ spokes; on the front it uses XLM-style ‘inboard flange’ (afaict).
Otherwise, tubeless rims are solid cast wheels and also have a lip (see image right) to locate and maybe even seal the bead of the tubeless tyre securely on the rim’s edge. It’s also considered a safety feature that stops the tyre coming off the rim should it deflate on the move.
But it also makes removing and mounting the tyre without bead-breaking tools difficult. It varies from bike to bike and tyre to tyre.
It seems Yamaha XTs have long had such safety rims on the rear, even though the bikes always came with tubed tyres. Out of interest, this disproves another urban myth: that you can only stick a tube in a TL rim to ‘get you home’ because it will eventually rub on that lip and explode with terrible consequences. Well clearly not on an OE tubed Tenere, lipped on the rear since the mid-1980s.
To convert the spoked rims to tubeless this lip is actually another good thing, and my 08 Tenere had them on the back wheel. The front rim was normal which might be a risk when running tubeless. But can it be any worse than a tubed tyre puncturing? Tubed tyres deflate faster – and therefor more dangerously – than tubeless tyres, so even without the safety lips on the front, with tubeless you’re already ahead.
Ways of sealing spoked rims
To run tubeless tyres on a bike with spoked rims you need to seal the point where the spokes screw into the rims at the nipples. Then you also need to fit a tubeless valve; easily done.
Systems like the US-made Tubliss liner are made for dirt bikes running low-psi, but are not approved for highway use in the US by the manufacturer, mostly probably due to homologation issues rather than safety. I know people who’ve run Tubliss for years on the road with no problems.
Tubliss work by fitting a tube-like ‘core’ which inflates to seal the bead of the tyre firmly against the rim; the image above depicts the way it works clearly. There core (the red thing) is a highly pressurised tube, but it’s kept away from the tyre sidewall or tread where punctures come through.
I’ve since bought a pair and fitted them to my 2012 project bike running 19″ spoked rims. Click the link to read more. Short version: not convinced they are suited to overlanding.
The Swedish T-Lock system is very similar as far as I can tell: the same non-elastic thick inner tube (blue, left) presses the tyre bead against the rim with very high pressure (110psi) to seal the tyre’s pressured chamber from the leak-prone spoke nipples.
The kit includes a separate rim band (green) and, if I understand correctly, the blue tube utilises the rim’s valve hole. This means the tyre must be filled with Slime-like sealant before final mounting and then pressurised by spiking the tyre carcass with a needle and then letting the sealant plug that hole. This seems to imply that you set the tyre pressures once. To reduce you’d have to puncture the tyre briefly, and to increase you’d have to spike-and seal again. Even more than the Tubliss, T-Locks are intended for motocross use, as the website’s imagery implies. Not at all suited to overlanding.
Another method is the Italian Alpina system pictured right (click to enlarge and read) which individually seals each spoke nipple with a rubber o-ring, and is sold for many road bikes and so must be considered road legal.
The benefits of this system and the Tubliss above is that spoke tension can be adjusted while maintaining the seal, be it nipple o-ring on at the bead. The permanently sealed bonding systems shown below may not work so well doing this, but as we know we’re usually talking very small turns of the nipple to adjust tension, and should a leak develop it can be re-sealed.
The latest idea I’m trying in late 2015 on my CB500X is a polymer sealing from BARTubeless, also from Italy (left). A bit like my 3M sealant below, but professionally applied. So far no air loss in 2000 miles. More abut them here and here.
Apart from using airtight cast wheels, the main way of building spoked tubeless rims is having the spokes mounted on the external perimeter of the rim, or on an ‘inboard’ flange as shown above left on a Honda XLMs from the 1980s. The current ‘out board’ design on the BMW GSA12 (right) looks strongest. Or you cn buy something like the beautifully forged Italian Kineo tubeless rim. For a Transalp that’ll be €1000 please.
DIY RIM SEALING
Knowing much less about this whole game at the time, I took the DIY option for my Tenere in 2008: sealing the well of the rim with a marine-grade 3M adhesive called ‘5200’ (below). It looks similar to the stuff you put round a bath edge, but costs £15 a tube from boat shops and presumably will last a whole lot longer in rough conditions.
My rims were in fairly good shape, being only 700 miles old, and once the near-new Tourances were removed (tried everything except the sidestand trick, but had to go to a bike shop in the end) I dried out any moisture with a hair dryer, cleaned them with lighter fluid and smeared the sealant all along the well.
The 5200 sealant I used was FC: ‘Fast Cure’ so set in a few hours. I used half the 300 mil for both rims. Unfortunately, the 5200 tube doesn’t work with a B&Q sealant gun, so I found it easiest to just cut the tube open and paste it on with a knife. I tried to leave no air gaps, small holes, or get any on the actual rim edges where the tyre bead sits. Once dry I refitted the rim tape (right) for added protection.
Now in 2012, it’s interesting to see Cyb’s version of doing the same thing on his spoked road bikes. Rather than slapping 5200 all over the well, he individually applied two coats of thinner, runnier sealant to each spoke nipple, and then topped them off with a thicker sealant. As he says, it means individual leaks can then be more easily located and dealt with. If I was doing this again, I’d follow his example.
Matey at my local tyre shop flogged me some tubeless car valves, but after hanging off the rim trying to pull them through I realised the holes on some tubeless rims, car or bike, must be a bigger 15mm diametre? A tubed rim hole for a Schrader inner tube valve stem is about 8-9mm. I started drilling but before I’d gone too far I got on the web and yes, there are two sizes as well as screw-in, two-part tubeless valves from about a fiver (see above left). My local tyre shop had an angled pair which screwed in with a lock nut from the inside around two rubber seals.
I had a pair of new tubeless Conti TKC80s and they levered onto the rims with a pleasing lack of drama. This was much eased by the fact that you don’t have to worry about pinching that darned tube and instead are able to concentrate on scratching your nice black rims. I did make some rim savers out of garden hose (right), but found they got in the way and could have ended up in the tyre (did that with a lever once in the desert. Took me ages to work out where it had got to!).
Mounting the tyres
This I knew would be the tricky bit. With no inner tube to inflate and push the tyre out onto the rim, it could take time and knack before the air pressure made the bead catch and seal on the lip and so pop it onto the rim.
It helped that I’d taught myself to do this on my old Land Cruiser’s 16″ rims, learning bead-sealing techniques such as clamping down the tyre with a tie-down, resting the tyre on another rim (or anything round like a bin) to get the lower bead to sit and seal on the rim under the tyre’s weight while putting a soapy inflated 16″ bicycle tube round the top to help make a seal (it worked).
There was even the ‘Icelandic Eruption’ trick (right); squirting gasoline into the tyre via the valve body (valve core removed) and lighting it in the hope that the small explosion inside would blast the tyre out onto the rim’s edges – it’s said to be commonly used in Iceland by off-roaders running huge tyres at low psi. What also helped at the time was having a decent 2.5 cfm Viair compressor attached to my car. Car or bike, a decent pump on the overland is an important accessory.
To cut a long story short it all took most of a day. At one point I looked for answers and ideas on the web. Tex on youtube made it look effortless with a sports bike tyre and a hand pump, but for me even going ‘Icelandic’ didn’t work, or I didn’t have the guts to use enough fuel; the tie-down clamp (right) helped, soap and water didn’t do much, running a bit of soft hose around the edge of the tyre to try and seal the escaping air (like the bicycle tube trick did so well on the Toyota) didn’t work either.
In the end it was just a matter of jiggling and technique: clamping the metal clamp of the tie-down right over the part of the tyre that was not mounted (so forcing the gap onto the rim), as well as manhandling the tyre, sitting on it, pushing and kicking it to get the lipless front tyre on. If you don’t have a chunky tie-down on the road, any rope or tape twisted tight with a stick will do to crush the tyre on.
Emboldened by this small victory after half-a-day’s pissing about, I eventually got the back one on too. The knack here may have been turning the car engine on to give my Viair compressor that extra bit of poke to ram in the air in faster than it could escape out the sides. Important: take the valve core out to get the air in faster. Once the tyre bead is seated on a rim it won’t come off, even at zero psi.
Once the bead ‘catches’ you’re on your way and you’ll hear the long-awaited creak of a tubeless tyre easing over the rim’s lip with that satisfying pop. Now screw the valve core back in and pump back up to normal pressure. I also added half a bottle of Slime (right) as a safety measure. Doesn’t always work I found on my desert car, but still a good idea.
With no air loss over a few days, I went to Morocco as planned.
Summary after 4000 miles in Morocco
For what they are TKCs are great road tyres, you forget they’re knobbly and on the dirt they manage fine, even at the road pressures I used. I’d use them again except that I don’t like to use the same stuff twice; it’s good for the book. I also forgot I was running on experimental tubeless and should have been monitoring the pressures more frequently. Winding around off piste on the way down to Erg Chebbi I did think, heck these shallow-knobbed, road-psi tyres are gripping unusually well in the sands! Turns out the back was down a bit but the front was way down – 10 psi. Amazingly I didn’t notice on the road.
On pumping up (the striped-out £9 compressor pictured above worked fine) I also noticed a tell-tale spurt on the front tyre where the Slime fluid leaked out the sides (right) as presumably I hit washed-out creek edges on the Col Belkassim track the day before. The rim wasn’t damaged so this suggested that even on moderate impacts (or possibly too low tyre pressures) the lack of the ‘safety lip’ (see graphic top of the page) was indeed allowing the tyre to collapse into the well or somehow lose its grip on the rim and so lose pressure; handily this was exposed by the Slime stains.
Whatever the cause, it was time to scoot over a couple of hundred miles to Bikershome in Ouarzazate, put the tyre on the operating table and then probably slot in a tube. Unfortunately my urge to tick off a few tracks on the way over went too far and I found myself up a pass (the gnarly Tizi n Ouli Ousir) with numerous problems including a flat front. I’d just ridden over some barely rideable rocks following a day of rocky tracks, and in all the excitement hadn’t kept up with the front tyre’s slow leakage. I imagine the under-inflated tyre transferred the sharp shocks to the rim while banging over the rocks; it in turn got dinged enough to lose pressure. Luckily there was one bar on the mobile if I stood on the right spot and Peter from Bikershome came to the rescue that night.
Back at Ozt I’d have like to have tested the wheel under water to see exactly where it was leaking, from the rim/tyre edge or out of the spokes, but the dinged rim would have flawed that experiment. I peeled off the 5200 mastic with unnerving ease. Tellingly, there was some very slight Slime seepage under the glue in places. I tightened up some spokes and Peter flattened the ding with a mallet, cleaned it up and slotted in a tube. I also discovered the vital 14mm Allen key I had to buy especially to remove the front wheel (it seems not to be included in the OE Yam toolkit) had fallen out of its resting place. Most of my trips have these ‘moments’ but deary me, it was not my day!
So, what have I learned. Well, on the dirt a thin-walled front tubeless tyre can have tough time, taking the brunt of the impacts. I don’t ride hard, especially when alone, but on a long trip there’ll always be times when you take a hard hit – rock, pothole, whatever – that you don’t react to quickly enough. I now think a safety lip on the front is probably important up to the point where a front rim gets dented. Then, unless you can bash it back you’re stuffed and will need a tube. After this episode I continued and watched the tyre pressures more closely and kept them at near road tyre pressures. Moroccan tracks are mostly rocky anyway.
As has been mentioned on the original HU discussion thread, for some reason tubeless 21-inchers have a bad reputation with holding their air, and outfits like Woody’s in the US which convert other spoked rims sizes don’t do 21s any more. Could it be the relatively narrow tyre profile of a 21-incher in relation to its height (for the same average tyre carcass thickness) allow it to ‘cave in’ under hits where a wider front – typically a 19-er – will take a hit ‘flat’ and maintain the seal? Is that why my 21″ Tenere front failed and is this why the BMWs F800GS has tubes (front 21″) while the ‘650’ version I used in Morocco has a 19″ tubeless on the front?
I spotted an ancient Honda XLM the other day outside the local cafe which reminded me that 21-inch tubeless fronts did exist back in the 1980s. I ran with one on my first Sahara tour (pic right, 1988) and recall no tyre problems, but I don’t remember if the owner fitted tubes for the tour. I really must get my memory upgraded.
Would the Tubliss liner mentioned above have faired better? One imagines yes, and that along with keeping tabs on tyre pressures, my 5200 sealing was possibly not good enough. Could the Slime have undermined the mastic’s seal? Would a lipped rim off an old XLM work better? Don’t know. A Tubliss liner was the next thing I tried in 2012, or I should try Cyb’s more precise sealant method.
I’ve been there, in the bush and out of tubes and patches. This is why tubeless is a good idea and it’s a shame that in Morocco I didn’t get the chance to establish where the leak was on the front, sides or spokes, but at the time I had a job to do.
The back tyre held up fine, kept its pressure following early loses, and has 5mm left after 4200 miles (left) so it looks like it would have lasted up to 6000 miles. Not bad for a TKC from what I hear. The front had plenty of tread left.
On the Morocco research trip in March 2012 I fitted Heidenau K60 tubeless on a BMW 650 and meet up with a mate who’s been using home made tubeless all round on his TTR with no problems. I also had K60s with Tubliss (right) on my 19-inch front and rear spoked GS500 project bike. More details here – short version. With the need to maintain the very high 100-psi pressures in the red tube, it’s not so suited to overlanding with humble mini-compressors.
It’s late 2015 and I’m not finished with tubeless spoked rims yet. The wire wheels that come on the CB500X Rally Raid kit got sent to BARTubeless in Italy who did a better job than what I managed on the Tenere wheels using some sort of polymer seal. More news on that here and here.
A 2015 article on running tubeless on Advpulse
It’s 2016 and I just came across Outex sealant tape. Some get on well with it, some don’t, as this post shows. Basically it’s a set of sticky pads for each nipple, a very sticky and wide doubled sided tape applied into the well with as few creases as possible. And then a thicker protective tape over the top. Application video below, a higher res app video here. Costs from $90 to $125. Take your time they say, to try and get all the air pockets out. Using an inner tube patch roller rasp (right) helps. You often get them with better puncture kits.
Also mentioned by ‘HluboDuc’ in that post: another DIY suggestion using glass sealant, being meticulous with your pre-cleaning and patient with your sealant curing – see below. Sounds similar to Cyb’s process at the top of the page.
1. Glass sealant which you can find in any hardware store.
2. 16″ Harley inner tube on ebay. 1″ smaller that our wheels to make it tight fit.
3. Glass cleaner or oven degreaser.
4. Loads of spare time…
• Clean the wheels with the degreaser/cleaner, wash with water to make sure that any chemical is washed off. Wait for a day in dry, clean environment, blast of air is indeed a great help.
• Apply the sealant to each spokes, wait for a day to cure, apply another layer, wait again.
• Apply sealant to the inner part of the wheel. One layer for one day, do it twice then wait until it’s completely cured.
• Cut HD inner tube to size so it covers the inner part of the wheel. Cut a hole for the valve and you’re good to go.
As mentioned before: with DIY or tapes, doing it to tubeless rims with the tyre bead safety lip greatly increases the likelihood of reliable sealing, especially if running lower pressures off road.