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-   -   Totally Tubular (https://www.bikeforums.net/showthread.php?t=154679)

CV-6 08-19-21 12:06 PM


Originally Posted by Hobbiano (Post 22190944)
I have a question that I'm sure some here could answer. I have a set of tubulars that I plan to mount with Jantex Competition 76 tape. Many years ago I rode tubulars for a while that I mounted with glue. I had a spare that was pre-glued. Now, if I flat with tape, and I take off my tire, and the tape stays on the tire, can I reasonably safely ride home on a un-glued & un-taped spare if I take it easy? No fast downhills or fast cornering on the way home. I'm thinking that I'd rather not try to do a tape job on the side of the road and I'd like to take off the spare and replace it with either the repaired flat or a new tire when I get home. Am I crazy? Lets assume I don't have sealant with me or it doesn't seal the puncture. Thanks for any advice.

Twice I have changed tires using tape on the road. First time, a good portion of the tape remained on the rim. Mounted a "clean" spare and rode home carefully. Second time the tape stayed on the tire. Just for that case, I had wrapped new tape around a piece of stiff plasticard and placed it in my seat bag along with a small pocket knife. I put strips on four "compass points" of the wheel and rode on. Did a proper tape job when I got home.

DiabloScott 08-19-21 12:25 PM


Originally Posted by Hobbiano (Post 22190944)
Now, if I flat with tape, and I take off my tire, and the tape stays on the tire, can I reasonably safely ride home on a un-glued & un-taped spare if I take it easy?

If you take it REAL easy, and you pump the tire up to a high PSI... you could ride home safely on a naked rim and an unglued tire.

Hobbiano 08-19-21 05:47 PM


Originally Posted by DiabloScott (Post 22191248)
If you take it REAL easy, and you pump the tire up to a high PSI... you could ride home safely on a naked rim and an unglued tire.

Is there any advantage to applying beforehand a coat of glue to the spare, when there's no glue on the rim?

CV-6 08-19-21 09:46 PM


Originally Posted by Hobbiano (Post 22191664)
Is there any advantage to applying beforehand a coat of glue to the spare, when there's no glue on the rim?

If you are swapping a spare in, then you will have glue on the rim.

Hobbiano 08-19-21 10:14 PM


Originally Posted by CV-6 (Post 22191914)
If you are swapping a spare in, then you will have glue on the rim.

Not if I'm using tape. I was just asking if a spare with dried glue would stay on the rim any better then without glue at all. Would the glue remain tacky over time? It's pretty clear how to handle a flat when gluing your tires on. But with tape I'm not sure. I guess I'll mount my spares without glue and see if they seem like they'll stay on just riding easy around the neighborhood (as a test). I'll do this before taping my new tires on. If they don't seem like they'll stay on I'll pack some tape with the spare like you suggested above. Thanks.

DiabloScott 08-19-21 10:55 PM


Originally Posted by Hobbiano (Post 22191664)
Is there any advantage to applying beforehand a coat of glue to the spare, when there's no glue on the rim?

I don't use tape, but I've heard usually there's lots of residue that stays on the rim. Sometimes it takes part of the tire's base tape too.

My spare is always used, so it has some glue on it - I'm pretty sure there's no disadvantage to putting a pre-glued tire on a pre-taped rim.

The other thing you have to be careful with, when riding a less-than perfectly glued/taped tire, is braking... the tire can creep around the rim and then the valve will get crooked and then there can be problems.

Rolling sew-ups off the rim is the kind of horror everybody's heard about; I have literally NEVER seen it... except for the famous Beloki crash in the TdF... and that was HOT, at race speed, and a steep winding downhill. A lot of the stories (especially criteriums) are crashes for OTHER reasons and then the tire comes off IN the crash rather than CAUSING the crash. So yeah be careful, but quit worrying.

https://cimg0.ibsrv.net/gimg/bikefor...a74f72b905.jpg

Hobbiano 08-19-21 11:32 PM

I've seen it happen once. This was around 1985. I was riding in a small group and we were nearing the end of a ride where we would often crank it up if we had any gas left. We were going pretty fast but not really sprinting, maybe 28 or 30 mph. We were drafting each other when the guy in front's front tire came off the rim! We were on a straight stretch of road and he managed to keep it upright as he rolled to a stop on the rim. The tire was still inflated and it just stayed right between the rim and the fork crown and off to the side of the rim at the bottom. I remember that the glue was not tacky at all. No telling how long he rode it like that before it finally came off. The glue must have just completely dried up or not been adequately glued to begin with. That's kind of stuck with me all these years.

DiabloScott 08-20-21 11:00 AM

https://cimg2.ibsrv.net/gimg/bikefor...6118a2dc9c.jpg

Checking your glue condition is a standard PM. Once a year is probably fine - twice a year if you're a worrier. Do it without air in the tire so you can really peel up the edges and look for the boogers.

tcpasley 08-23-21 11:04 PM

Question about Velox Jantex Competition 76 Tape
 
Has Velox Jantex Competition 76 tubular gluing tape been changed/upgraded in recent years?

On vendor sites, I often see Velox Jantex Competition 76 tape referred to as "Belgian tape" that "Must be used in conjunction with tubular glue". These sites usually have a picture of a yellow-tan roll of tape. However, the Velox.fr website shows it as looking more like Effetto Mariposa Carogna tape, but with a pink color, and says nothing about it being Belgian tape. Nashbar.com mentions "New formula for 2015" but contradicts itself about the need to use glue with it.

I know about Belgian tape, used for 'cross tubulars (https://cyclocrossworld.com/how-to-g...-belgium-tape/), but Velox Jantex Competition 76 ain't Belgian tape. I'm just curious about all the confusion in the product descriptions, and wonder if I should try to order some from a website that shows the newer pink stuff. Maybe the distributor (QBP?) is giving all the vendors inaccurate product information. Any advice is appreciated.

Shrevvy 08-24-21 05:23 AM


Originally Posted by tcpasley (Post 22197870)
Has Velox Jantex Competition 76 tubular gluing tape been changed/upgraded in recent years?

On vendor sites, I often see Velox Jantex Competition 76 tape referred to as "Belgian tape" that "Must be used in conjunction with tubular glue". These sites usually have a picture of a yellow-tan roll of tape. However, the Velox.fr website shows it as looking more like Effetto Mariposa Carogna tape, but with a pink color, and says nothing about it being Belgian tape. Nashbar.com mentions "New formula for 2015" but contradicts itself about the need to use glue with it.

I know about Belgian tape, used for 'cross tubulars (https://cyclocrossworld.com/how-to-g...-belgium-tape/), but Velox Jantex Competition 76 ain't Belgian tape. I'm just curious about all the confusion in the product descriptions, and wonder if I should try to order some from a website that shows the newer pink stuff. Maybe the distributor (QBP?) is giving all the vendors inaccurate product information. Any advice is appreciated.

Jantex did change their packaging and description. They also changed the tape, but I believe it was more the backing strip that was changed to something that tears less when installing. They must have transitioned packaging at some point becuase QBP was sending out tape in two different boxes. This box clearly gives instructions without using glue. The older red box did not. If you want to try a box of this, shoot me PM.

https://cimg0.ibsrv.net/gimg/bikefor...0ef0403efb.jpg
https://cimg1.ibsrv.net/gimg/bikefor...7f571a0d1c.jpg

RustyJames 08-31-21 10:30 PM

I used the Velox tape and it didnít say anything about using glue. I didnít use glue and so far all seems well.

masi61 09-03-21 12:18 PM


Originally Posted by Classtime (Post 22190714)
be aware that the Major Toms are wide and are inappropriate for 25mm or less tires. I built some for CX and thought I might use them also for road rides with 25s and the radius of the MT was too large for a good gluing.

Can you share which tires you were proposing to use with the Major Tomís for road? What is their width?

Classtime 09-03-21 12:36 PM


Originally Posted by masi61 (Post 22213683)
Can you share which tires you were proposing to use with the Major Tomís for road? What is their width?

25mm Sprinter Gatorskins. I mounted them and with glue and 90 psi, the radius of the tire was significantly less than the rimís. There was a gap on both sides when the tire was centered. While the tires were secure, the gap would have filled up with sand/dirt/etc. I didnít try 28s because my road bikes donít have the clearance.

masi61 09-03-21 01:15 PM

Classtime - sorry the Sprinter Gatorskins did not work out and sorry your frame cannot accept 28ís.

Any chance that a bonded (not a ďsew-upĒ) tubular like a TUFO or a Conti GP4000 tubular with more of a flat base tape might work better in the 25 mm width?

Classtime 09-03-21 01:46 PM

Somebody else is racing CX on those Major Toms. My go to road tire is a regular 22mm Sprinter. And the 25mm Gatorskin is for Eroica, The BWR, and one day, Cino. (Those 22mm Sprinters on 7900/Nemesis felt pretty awesome today.)

masi61 09-03-21 01:58 PM


Originally Posted by Classtime (Post 22213861)
Somebody else is racing CX on those Major Toms. My go to road tire is a regular 22mm Sprinter. And the 25mm Gatorskin is for Eroica, The BWR, and one day, Cino. (Those 22mm Sprinters on 7900/Nemesis felt pretty awesome today.)

Oh - gotcha.
I have Major Tomís (polished) built up with Chris King road hubs into a custom road wheelset. I have not ridden them yet but hope they work for me for road.

HM70 09-06-21 08:55 PM

Need to get new tubs like my Strada
 
Lohttps://cimg2.ibsrv.net/gimg/bikefor...f89d6697c3.jpg
Love the way these ride... gifted to me by a friend. But it seems the new Strada has a synthetic sidewall, spun poly or something. These look like Egyptian cotton judging from the outrageous psi rating but I don't know. As a recreational rider 150 lbs they run great at 90/100psi. I vaguely remember how a great tubular like the clement seta rides from the 70s so I'll be disappointed if the new ones don't have a good feel and sound. And I'll be damned if they don't have a tan sidewall! Should I go for it?

Miele Man 09-11-21 01:11 PM

I just put a pair of Servizio Corse tubular tire onto the rims. Unfortunately the rear tire isn't sitting quite right at the valve stem and thus there's a bit of a bump every revolution. What's t he easiest way to get the tire to sit on t he rim perfectly round. I haven't applied the tape yet because 1. I was wanting to stretch the tire prior to doing that and 2. I wanted to be sure the tire was perfectly round on the rim.

Thanks and cheers

smontanaro 09-11-21 01:22 PM


Originally Posted by Miele Man (Post 22225656)
I just put a pair of Servizio Corse tubular tire onto the rims. Unfortunately the rear tire isn't sitting quite right at the valve stem and thus there's a bit of a bump every revolution. What's t he easiest way to get the tire to sit on t he rim perfectly round. I haven't applied the tape yet because 1. I was wanting to stretch the tire prior to doing that and 2. I wanted to be sure the tire was perfectly round on the rim.

In his wheelbuilding book, The Art of Wheelbuilding, Gerd Schraner specifically mentions countersinking the valve stem hole to provide room for the "shoulder" on the tire around the valve stem. I can't find the quote in my copy, but as I recall, he implied this bit of work should have been done by the rim manufacturer. Obviously, different rim/tire combinations will require more or less work in this regard.

Classtime 09-11-21 06:40 PM

I've never mounted Servizio Corse tires but Is is very important that you mount the tire with a great deal of stretching force from the beginning -- at the valve -- or you end up with more tire at the valve. And if the base tape is doubled at the valve? Well?

JohnDThompson 09-13-21 06:58 AM


Originally Posted by Miele Man (Post 22225656)
I just put a pair of Servizio Corse tubular tire onto the rims. Unfortunately the rear tire isn't sitting quite right at the valve stem and thus there's a bit of a bump every revolution. What's t he easiest way to get the tire to sit on t he rim perfectly round. I haven't applied the tape yet because 1. I was wanting to stretch the tire prior to doing that and 2. I wanted to be sure the tire was perfectly round on the rim.


Originally Posted by Classtime (Post 22226031)
I've never mounted Servizio Corse tires but Is is very important that you mount the tire with a great deal of stretching force from the beginning -- at the valve -- or you end up with more tire at the valve.

I've had good luck with the YJ Servizio Corse tires being both round and straight. I note that @Miele Man has not yet glued the tires onto the rims. That is good. I always stretch my tires on rims for several days or weeks (or even longer) before fully mounting them; it seems to help minimize lumpiness. Once you have the tire on the rim, pump it up to at least half pressure and let it sit, the longer the better, before gluing them down.

squirtdad 09-14-21 10:13 AM


Originally Posted by Miele Man (Post 22225656)
I just put a pair of Servizio Corse tubular tire onto the rims. Unfortunately the rear tire isn't sitting quite right at the valve stem and thus there's a bit of a bump every revolution. What's t he easiest way to get the tire to sit on t he rim perfectly round. I haven't applied the tape yet because 1. I was wanting to stretch the tire prior to doing that and 2. I wanted to be sure the tire was perfectly round on the rim.

Thanks and cheers

i use the method posted on yellow jacket....really important to seat the valve them and then stretch hard going away, I got lazy once and got the bump and had to take off re glue and remount

Tubular Tire Mounting Cement Gluing Adhesion by Yellow Jersey; Thoughts on a Front Wheel

Lazyass 09-15-21 02:59 AM

I only pre-stretch my tires if they're super tight and then I only stretch them overnight. I've never had problems with lumps if they aren't stretched.

Miele Man 09-16-21 09:01 PM

Yesterday I manage to g et rid of the hop near the valve stem. Unfortunately te tire now has a hop in a different location. I didn't feel like messing with it today.

Funny thing is that the front tubular tire went on the wheel with no hop at all.

I shall persevere and get this rear wheel t ire hop out... eventually. I'll let you all know when that happens.

Cheers

Lazyass 09-17-21 02:05 AM

I've mounted tubs so many times now that I'm good at getting the tension even all the way around the first time. If I do an up getting a lumpy spot I'll just pull over to the side of the road, remove wheel, deflate and readjust the tension to stretch out the lump then air it back up and continue the ride. Not a big deal.


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