For starters, when I lived in New Mexico, goathead capital of the world, I got very few flats with either clinchers or sewups. I rode on sewups for most of my recreational riding (and training/racing during the year or two that I dabbled in that activity).
My favorite tires were Clement Paris-Roubaix red label cottons. They had about a 28mm - 29mm cross section compared to my next favorites, Campionato del Mundo setas which were 26mm -27mm.
I ran those tires at 85-90 psi. That was one of the secret we found to help reduce puncture flats. I would probably have run higher pressures with smaller cross section tires.
We also used "sticker flickers" - tire savers made of soft wire and surgical tubing. We had someone custom make them for our shop. He used the softest Tygon brand tubing available. I recall riding over a patch of goatheads on the road and watching the sticker flicker "flick" them out of my front tire before they could puncture from the 2nd rotation.
The third thing was to try to avoid riding in the gutter or close to the edge of the road whenever possible because that's where goathead thorns and glass accumulated.
Last fall I read about Tufo Sealant so I got a bottle to try. In November I received a classic bike from a seller in Colorado.
The sewups were flat. One would hold air for about 15 minutes, the other went flat instantly. They were a matched pair of decent quality tires with removable cores. I inspected the tires and pulled at least 15 goathead nubs out of the treads before I started.
I followed the Tufo instructions and the tires are still holding air after 9 months. I haven't ridden on them yet as they need to be re-glued.
Over the next few months I acquired about 20 more old sewups from about 5 to over 35 years old. Here's what I found from playing with those tires: old latex tubes are probably too deteriorated for any sealant to do much good; Tufo Sealant doesn't work on sidewall cuts; same with tube damage caused by the valve stem.
The Tufo Sealant works best on small holes like those resulting from goathead thorns and small glass or metal cuts less than 1/2mm in size.
The way Tufo Sealant works is that it leaks out of the hole or holes and glues the tube to the casing forming an air tight seal. The liquid is fast drying and seems to be much stronger than standard liquid latex.
I like your idea of putting the wheel in a stand. Next opportunity (hopefully not to soon) I'll give your method a try.
Another CR member suggested 2 new sealant products in their response to this thread. I'll have too look into them. I love riding sewups but my days of patching them ended about 30 years ago.
I used Tire Life back in the 70s. It worked OK. The new stuff seems to be a little different formulation. The old stuff could be used to re-glue the base tape. I wouldn't trust the new stuff. Both the old and new Tire Life hardened in the container too soon.
I used to use a rubber patching cement made for hip boots, waders and so on. It was a latex compound about the consistency of tooth paste. It worked really well for re-gluing the base tape, also for applying a boot inside the casing. I used to thin it a little and use it like Tire Life.
Chas. Colerich Oakland, CA USA
George Hollenberg wrote:
> Chas:
> Thanks so much for answering-I appreciate it.
> I agree that Tufo recommends much too much sealant-especially for period
> tubulars. I use much less with excellent results. I have had to replace
> valve cores several times, but this is easy and the expense trivial. I
> have never used the Tufo sealant with the tubulars I use to ride (not
> period bikes).
> Please let me know how your plans work out.
> I had thought to do something a bit different. My plan was, put the
> wheel/tubular in a truing stand, put the sealant in, inflate to partial
> pressure, spin for enough time to allow some drying, then with the
> valve at 12 o'clock, add more air to full pressure (hoping to blow back
> any sealant present in the valve back into the tube, and then let the
> tire sit with the valve at the 12 o'clock position until fully dry,
> letting the sealant drain out of the valve.What do you think of this?
> Chas, there is one other thing I don't understand, I thought I had to
> use a bottle and tube with non-removable valve cores (to fit around the
> valve stem)? And you're right, this might well create a mess. Is there a
> kind of bottle that fits around the valve stem? I've never seen this.
> Please let me know.
> The stakes are high in my case, since I have several sets of Clement
> Critierium Seta Extras. These are NOS, and not punctured, but hold air
> for only a short time. I know it's just a matter of time before they
> won't hold any air.
> Another thing that interests me is the use of "Tire Life". I've used
> this stuff for a long time, but, in truth, it's not very good,
> especially on silk tires.
> A few weeks ago, an old mechanic told me to buy latex in a carpet store
> and paint that one the side walls. Have you ever head this?
> Best regards,
> George
>
<snip>