Pacenti Tubeless Tape and Valve System - Review
Pacenti's blue tubeless conversion tape is similar in color and consistency to the system that Reynolds sells (which I have used with excellent results), so I had high hopes. One roll is advertised to seal up to four 29er wheels and widths are available in 21, 25 and 29 millimeters, which covers the entire spectrum of conventional mountain bike rims from XC through DH. Pacenti also sells a valve stem kit that features a 40mm aluminum stem with a tapered rubber plug and a removable brass Presta valve. Tape sells for $11.25, $13.50, and $15.75 USD, depending upon the widths, and the two-valve kit runs $19.00. Pacenti tubeless conversion tape and valves can be purchased at select bike retailers or Pacenti's online store.
Pacenti's aluminum Presta valve has a tapered rubber stopper similar to Stan's, and a removable core.
We assume that this was an isolated event, but the rubber de-laminated from the valve stem.
Pacenti's 25mm wide tape will fit perfectly between the flanges of most 23mm inside-measurement rims.
We used the 25-millimeter-wide tape to prepare two Commencal Alpha 27.5-inch tubeless-ready wheels. The tape is strong and not very stretchy, which makes it easy to guide the film between the rim flanges to keep it centered. The 25-millimeter width fit snugly against the inside of the flanges, covering the rim's entire inner width. Alpha rims measure about 23 millimeters between the flanges and 28.5 outside, which is pretty much the old-school standard for wide, all-mountain hoops from the likes of Mavic, DT Swiss and WTB. We cleaned the rims thoroughly, but from the outset, we noticed that Pacenti's tape did not have a strong adhesive, and after wrapping the rims with a single layer of tape, we spent a measure of time rubbing the tape with a soft cotton cloth to work out the air bubbles and get adequate adhesion to the rim. The tape was perforated with a tapered punch at the rim's valve hole to ensure a good seal and the valve stems inserted and secured.
Twice we had air leaking through the valve-stem hole - once due to a defective valve, and the second time was caused by leaky tape.
Mounting and inflating the wheels to Maxxis High Roller II and Ardent tires was a mixed bag. The tires were charged with Caffelatex sealant and they both mounted and aired up quickly, but the rear tire would not stay pressurized. The problem was a broken seal where the tapered rubber plug was bonded to the Pacenti valve stem. The bond had separated, which released air regardless of how tight the stem was cinched to the rim. A spare valve stem from a second Pacenti kit fixed the problem. It should be noted here that tapered type valve stems, like Pacenti and Stan's, require a loose fit in the rim to impart a secure seal. Stems with the block style stoppers seal better if the hole is a snug fit. The Alpha rims were drilled just large enough to make use of a tapered type stem.
Two days later, the front tire was inexplicably losing air. A tear-down inspection revealed that the adhesive where the tapes overlapped had lifted, allowing sealant between the layers, further undermining the adhesive until the overlap was no longer air tight. A smilar situation was beginning inside the rear tire. The fix was to clean and re-wrap the front rim a second time, using a longer, 300mm overlap, which did the trick. We left the rear as it was without further incident.
Pinkbike's Take:
 | After successfully sealing a number of wheels using inexpensive Gorilla tape, the main reasons that I would purchase a taping kit from the likes of Stans, Reynolds or Pacenti would be for convenience, because I needed a special width, or to ease the task of mounting up a tightly fitting tire by using the thinner tapes that most aftermarket kits offer. My experience with the Pacenti tubeless sealing tape and valve stems proved to be more troublesome than using the Gorilla tape option. Pacenti's kit gets the job done well enough, but there are better options available. - RC |
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Hockey tape under the Stan's rim strip helps build up the base. You can set it up to be able to pump up a tire with a hand pump that way. I did this for a decade with great success and just recently went to UST wheel sets on both my rigs.
They are lighter but my tires burp more frequently.
Any time I used Stans tape it eventually leaked. Every time I've used Gorilla tape I've had zero issues.
+ Stans is very expensive for a "simple" scotch.
That's providing you are using the old school Stan's No Tubes rubber rim strip with the valve. I've NEVER had a burping tire nor a leaky valve issue with these. I think they stopped making them, pity that.
Tires sat and held air well even without sealant! (Of course, I added sealant before riding)
I read on here about the gorilla tape method and using a tyre/tube at 40psi for a couple of days to set the tape firmly, I put on a maxxis minion non tubeless tyre with the normal amount of sealant and it worked well, I lose about 2psi over 7 days which is ok by me, thanks pb for the great tip with the gorilla tape I was ready to go back to tubes
Another problem I had was if I cut the tape to width before putting on the tire because sometimes the tape would not stay stuck down in the valley and once I put air pressure the tape got pushed down into the valley pulling the sides out which made a gap.
My trick, start the wrap a few inches past the hole, pull straight and tight while wiggling it from side to side so it fits down into the rim. If your rim is narrower and needs to be cut, no problem do the same then once you've passed the hole a few inches cut the tape. Get a plastic tire lever and with the sharp edge, shove into the bead groove on the inside of the rim and slide it firmly all the way around until everything is pressed down firmly. Then get a utility razor knife and run it in the wheel bead groove on the inside to cut the thin piece all the way around. It's easier than it sounds the knife naturally wants to stay in that groove so there is no wandering. Do it on both sides and the puncture a small hole in the stem hole part of the tape,(DO NOT CUT A LINE OR X, IT WILL CAUSE LEAKS!) put stems through holes and tighten snugly and your done with the taping. It has never failed.
Just amazing that someone will try to sell a valve for more than a set of tubes - with valves.
Pro-tip - smear some silicone sealant on the tapered rubber valve stem plug and you'll *never get leaks at the valve hole.
*pretty much mostly never.
Also I used the e-thirteen 2 piece valves and along with the tape, my Wickens & Soderstrom No8 sealant and Schwalbe tubeless easy tyres I set up my first tubeless wheels without a single hitch also with my high volume Lezyne trackpump.
Make sure to clean your rim well also because if it is wet (if sealant made its way under the tape) then the tape will not stick.
Its kinda hard to find gorrila tape in my place
Gorilla tape is also available on amazon in the US, you could probably order it & pay import duty if you really want it.
650b/27.5 has basically taken over, eliminating 26" and cutting into 29" sales. That is kind of a big deal.
The dimpled bar is an easy solution no one else did, and is way more practical and aestheticly cleaner than the Moondraker solution.
I don't think he ever promoted the tape and valves as innovation, just a compliment to his wheel/rim business.
What I appreciate is that he put 650b out there without ever preaching to the extreme the way companies like Niner, claiming their way was the only way.
(Waki - you're going to lose all credibility here with a pic feature an e-bike on your profile... )
I am not sure though if he has any bigger influence for 650B taking over, or rather being imposed. The first phrase may slightly suggest that there was a choice....
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