going tubeless or not

Earlier this year I bought a new bike which was intended as a winter training / light touring / audx machine. As standard it would have been supplied with 32mm tubeless tyres but at the time I wanted to run it in “winter” mode so I took delivery of it with mudguards, 28mm Continental GP 4 Season tyres and tubes. The Continentals being my choice of a fast and well reinforced tyre to deal with the poor state of the roads in Surrey in winter.

However with summer here it was time to ditch the ‘guards, go for some wider rubber and head for the kind of cycle paths, bridleways and unmade roads that are off limits to a road bike in the winter months. (note I have specifically avoided use of the “gravel” word)

For road cycling I have stayed with tubes. I swapped to tubeless on my mountain bike many years ago and have never regretted it. However road tubeless seems less sucessful and many friends have had bad experiences, most eventually going back to tubes. The higher pressures of road tyres seem to be beyond the capabilities of the current range of sealants.

So what about some 32mm tyres running 60psi? Thats kind of half way between the typical 90psi road and 30psi mountain bike sets ups right? Perhaps that will work OK? So I thought I would give it a go. . . .

the componenets

The first decision then is the tyres themselves. As somebody who normally over analyses every purchasing decision it settled on some Panaracer Gravel King tyres without too much thought. They would have been the standard fitment on my touring bike had I not specified a tube set up. The guys liked them a lot and they are generally well recommended on the usual internet hangouts. Done.

The next decision was, sealant. I have previously used Stan’s original on my mountain bike and that has served me well. I have obvious evidence of multiple punctures being sealed without being aware of any. However in road use I know of a few people who have had issues with Stan’s not sealing even relatively small holes from thorns and such like. So I was on the look out for a better sealant. There are lots of reviews and tests out there on the web and many brands of sealant do not seem to fare well. I eventually settled for for Muc-Off No Puncture. It’s the new kid on the block and promises better sealing performance for road an mountain bike use so that was decision made. It also smells nice.

The last part of the tubeless puzzle of course is the valves. I have used Stan’s valves successfully on my other bike so bought a pair without too much thought. I was certainly not going to stretch to funky aluminium valves on a touring bike.

So with all the bits assembled it was time for some fitting action.

the installation experience

First up the Panaracer Gravel king tyres are are very, very tight fit. They are certainly not going to come off the rims easily. I actually needed tyre leavers to get them on. That was a bit of a worry as my normal procedure for fitting tyres like this that come folded is to fit them first with a tube and leave them over night so they take the proper shape. Anyway I got them fitted without pinching the tube and came back the next day to refit – tubeless.

Then the problems really started. Try as I might I could not get the beads to seal. For my mountain bike I have a large volume pump and with a bit of enthusiastic pumping I can get the tyres to pop onto the rims quire reliably. However these Panaracers would just not seat whatever I did, the old soapy water trick made no difference. Out of options I went looking for another solution. After a bit of research I discovered the “Airshot” a cylinder you pump up to 160psi then discharge in one hit to pop tubeless tyres onto their rims. Better still I found the identical product branded as the Schwalbe “Tire Booster” for a bit less money. So that was that, with a Tire/Tyre Booster on order my Continental Grand Prix 4 Seasons with tubes went back on the bike and I waited for the postman.

The Tyre Booster arrived a week later. Whist not cheap its a nicely made thing. It comes with a nice rubber and Velcro strap to secure it to the barrel of your track pump which is neat. My only reservation is the valve on the top from which you fill the tank. It looks a bit exposed and I am rather worried that it will get damaged easily if the whole rig is chucked it the back of your car . . .

Anyway, good news, with a bit of soapy water and a blast of air my tyres popped straight on the rims. Oh Yes.

So my next strategy when fitting tubeless tyres for the first time is to inflate them “dry” i.e. without sealant and check the whole set up is broadly airtight, then add the sealant. Again I would normally leave overnight but in this case that was not necessary. There was a huge leak from the valves, I tried pinching up the lock ring with a pair of pliers but there was still a massive leak. It would seem that the Stans valves with a conical rubber plug were not a good match for my rims with a deep rounded rim bed.

I tried all kinds of tricks, I shaved down the sides of the rubber plugs with a scaple to get them to site lower in the rim bed. That helped a bit but there was still a massive leak. I cut a small square of old inner tube, cut a small hole in the middle and pushed the valve stem through so the square of inner tube acted as a kind of washer or gasket. That helped a lot as well, but again there was still a very noticeable leak. Out of options again the Conti GP 4 Seasons when back on.

I then found some Mavic UST valves that have a rubber plug with a half round shape that looked to match the rim bed of my wheels. So that was my next internet purchase.

A week later 2 valves dropped through my letterbox and I was off to the garage. This time they sealed first time without issue. I soap tested the entire set up to convince myself I had a sealed system and then injected the Muc Off. All still seemed fine so that afternoon I went out for a short 30k ride to test the new tyres out and all was good

the ride experience

Since then I have ridden over 200k on the Gravel Kings so I am starting to get a good feel for them. Running at lower pressure (60 vs 85psi) it is a slightly more comfortable and compliant ride. The main improvement I noticed was the absence of the higher frequency “road buzz” that can lead to numbness in hands and fingers for me. That has completely gone away which is great for longer distance rides.

The bike also feels more sure footed, it is particularly noticeable on fast descents with poor tarmac where 25mm tyres pumped up to 90psi can skip alarmingly over surface imperfections. The 32mm Gravel Kings seems to soak up the undulations and maintain contact with the road at all times. That extra grip inspires so much more confidence.

It is also feels like a very noticeably lighter set up. The bike seems to accelerate faster from a standstill and it feels more nimble on climbs. I have not weighed the components but a quick check of the manufacturers websites suggests there is a weight saving but not as much as I perceive. Perhaps it’s the issue that small weight savings are accentuated if they are from the rotating mass on the rim of the wheel. Or maybe its because the tubeless tyre is more supple?

Component	Weight
Continental GP 4 Season 28mm	280g
Continental Race Wide Tube	125g
Total Tube Set up	405g

Component	Weight
Panarager Gravel King 32mm	290g
Muc off Sealant	60g
Mavic UST Tubeless Valve	7g
Total Tubeless Set up	357g

I also felt no sensation of there being any extra rolling resistance from the tyres which might be expected from the lower pressure and fine cut tread pattern. Though that is probably the most difficult thing to determine. However I checked my ride data on returning home to find I had scored a new PB on a local hill so certainly no worries in the “speed” department for this tyre set up.

compare and contrast

In their construction the Panaracer Gravel Kings could not be different from my usual Continental 4 Seasons. Whilst I have always like the Contis, my one criticism is that the rubber compound is optimised for longevity making it a bit hard and short on grip especially in the damp and wet. This always seemed like a strange choice for a winter tyre and I have always been cautious on fast, wet decents. In contrast Gravel Kings are soft and super grippy, they feel like they will stick to anything. The down side being that they will surely not last very long.

The lightness that I have talked about also comes at a price and that is the robustness of the tyre, they certainly don’t have the bullet proof construction and feel of the Conti 4 Seasons. That does seem odd for a “Gravel” tyre. They will clearly not offer much puncture protection on their own and will rely heavily on the sealant. I worry that a clean cut from a flint or piece of glass could see them split open unlike the heavily reinforced Contis. I am not sure I would want to use these on long rides away from support.

the wrap

So as you might tell I am still not completly decided about this set up. I am going to need to ride these for a few months before I get a really good view of their overall performance.

Firstly set up is a real hassle unless you are lucky enough to get it all right off the bat. It took me 3 weeks start to finish to get these working. At close to £30 for a bottle of sealant its not a cheap solution either.

However they ride well, grip well and go fast. Perhaps that is all you really need to know.