My Suzuki GS-R runs 19-inch SM Pros and the plan was always to have them running tubeless, hopefully doing a more successful job than I did on my Tenere’s wheels a couple of years ago. On that bike the sealed-up rear never missed a beat, but the 21-inch front leaked off road and as I failed to monitor it, it got soft enough to ding a rim on a gnarly Moroccan climb and with that lose all pressure.
Back then I wanted to try Tubliss but they weren’t sold in Tenere sizes in the UK at the time. Now I have them for the GS-R, picked up in the US for around £55 each.
I was expecting a hard time fitting them in my Heidenau K60s – it’s a stiff tyre and you’d imagine the bulk or shape of the red plastic core and rim-lock might make tyre mounting even harder. When a sunny afternoon came by, I left the 4000-mile old K60 out against a wall to warm up a bit and then followed the clear instructions carefully. Off with the old Cheng Shin without too much difficulty, clean off the duct tape/rim tape residue and the drill an 11mm hole a few spokes up from the regular valve hole. I then talc’ed the inside of the red liner to slide better against its mini tube, lined up the rim lock clamp/tyre inflation valve and the nearby core inflator valve with the two holes in the rim (pic above; the instructions stress this is critical) and then mounted the core onto the rim.
How it works
Tubliss works by using a small but extra thick bicycle-sized inner tube at very high pressure to force apart the thick red plastic core against the inside of the rim and tyre bead so as to seal off the spoke nipples where air would otherwise leak out from the tyre’s air chamber. This can be an odd concept to get your head around; a mini-tube is still used and so to protect the valve a rim lock is required. However the mini tube is not pushing and rubbing against the inside of the flexing tyre carcass and so it would take an exceedingly long spike to puncture it and everything remains cooler, just as with regular tubeless tyres. This way you can still true spokes, something with might not be so easily achieved with the spoke nipple-sealing method I used before. The rim lock is clamped with a ‘hollow bolt’ which is also a valve to inflate the tyre to a regular pressure. The usual valve hole is used to inflate the mini tube to 100 psi.
The core went onto the rim easily, even though the red plastic element is not elasticated. As long as you follow normal bike tyre mounting techniques: make sure the red core is right down in the well of the rim as you lever with your hands on the other side of the wheel. Usually I use diluted washing up liquid but that tends to dry up quickly; this time I used more slimy 303 UV Protectorant; it’s the same as Armor All that Tubliss recommend. The core slipped on with no levers, just like on the Tubliss youtube demo. (Since then I fitted a stiff Maxxis Desert tyre on a CRF using WD40 which was all I had at hand, and that worked fine too. WD40 is not an oil, as many people think).
Next came the tyre. This was going to be hard, or so I thought. I double checked I had the direction arrow in the right orientation and then pushed the wheel down into the tyre using the folded metal plate which Tubliss supply, rim-lock down. Following the instructions closely (and having changed a few tyres in my time), the plate did genuinely help the core-fitted wheel slide into the tyre with less effort than normal, and if you kept pushing down as they advise, with a bit of many-armed Vishnu-ing I got the wheel inside the tyre walls.
The rest – levering the tyre walls back onto the rim – was like regular tyre mounting: minimal possible lever force and maximum lube, while always making sure the tyre opposite the levers is being kicked and crammed into the tyre’s well (central dip) so as to free up the vital slack for the levers. Like they say on the leaflet, that plus lube is the key. In the end the last bit of tyre went on without the final lever. This used Heidi was not so hard to mount after all. The same-sized new K60 for the back was a bit more effort shoving inside the wheel, even with the Tubliss plate, but with slack and lube, it all got mounted.
With all this done the next step was to see if the system held air once everything’s pumped up. There’s no reason to think the mini tube got pinched, protected as it is inside the red plastic core. The key is the red liner sealing against the bead of the tyre to keep the tyre at the right pressure. You need to put 100 psi into the mini tube to make sure it seals and I doubt your average moto mini compressor will have the power to do that, but that should only be needed when you remove the tyre. The whole point of running tubeless is that punctures are simply plugged with the tyre in situ and the tyre reflated as normal.
You read complaints that fitting Tubliss doesn’t work first time round or doesn’t work at all – the tyre goes down – but so far overnight both tyres have held their pressure. Checking the tyre and core pressures after 10 days, I found the back core down by about 10% and the front tyre down by the same. I think that’s acceptable and can’t be sure everything was at the right or equal pressures to start with so I topped it all up to 100 psi and 33 for the tyres and will check again in a while. Tubliss do say to check pressures before each ride. Unfortunately, checking the high pressure cores seems to have blown the brains out of my digital tyre gauge (right) and those metal sliding rod types only go up to 50 psi. A tougher high-pressure tyre gauge may be in order. I have a CyclePump gauge (left) that’s sat around for years and whose time may have come. I lent my CyclePump out years ago and never got it back but as mentioned, a mini-compressor able to deliver 100 psi without similarly fatal results will also be in order. Not sure a CPump or anything like it can manage. My not-so-bike-portable car compressor takes some poke to get the cores up to 100 psi.
Technically the cores can be checked when at garages with automotive pumps. Should you have a flat on the road it’s only the tyre chamber that loses pressure in the normal 30-40 psi range which, once plugged can be reinflated with a regular mini-compressor. Because Tubliss don’t claim to be suited to road use let alone overlanding, your average rec rider with a Tublissed MX bike will have a garage or a pickup with a powerful compressor to top up the cores. On the road and out in the world a reliable mini-compressor is a vital tool.
A mate with Tubliss in his TTR has had no probs, including air freighting it around the world. He’s reminded me that putting sealant like Slime/Oko/Ultraseal is a good idea and over time helps seal the tyre right up. I did the same to the Tenere when I sealed those wheels (right) and if nothing else it helped highlight leaks out of the front.