Mounting tublars

mace112961 said:

Okay,

So I'm thinking about taking my first attempt to mount my own tubulars. I come here and other boards and read a dozen "How to" posts. Most everyone agrees with the same basic method:
1. apply first coat let dry 24 hours,
2. apply second coat let dry 24 hours,
3. apply third coat and mount.

Several differing opinions on the best glue, but most everyone agrees Vittoria's Mastik One is a good choice.

I get a can of the glue and I'm ready to take on the project............. until I read the direction on the can!!! The directions totally conflict with the board advice:

1. Sandpaper rim (new or used) clean with solvent and leave to dry.
2. Clean the seam cover band of the tubulars slightly dipped in solvent
3. spread a thin layer of Mastic over the rim and over the seam cover
4. After 5-10 minutes maximum apply second coat of glue on rim only
5. Leave to dry for 3-5 minutes maximum
6. Mount the tubular on the rim, inflate slightly and center
7. Inflate to working pressure

Should I follow the directions of the board (presumably people that have done this lots of times) or the instructions from the company?

I'm open to any and all opinions and advice.

Regardless of WHICH instructions you follow, YOU MUST PRE-STRETCH A NEW TUBULAR TIRE (on an spare/old rim) otherwise there is no way on Earth that you will get a new tubular on the rim without making a mess of everything.

I recommend something closer to the second set of instructions ...

THE FOLLOWING IS ONE EXTREME GLUE-UP TECHNIQUE (and, not necessarily recommended):

When I used to use sew-ups (as recently as just a few years ago) I used the MINIMUM amount of glue you can imagine ... but, I wasn't racing.

After decades, it got to the point where I was basically putting a DAB between each spoke hole (36h wheel), and then rolling a NEW (as in clean) BARELY INFLATED pre-stretching tire onto a "clean" rim ... "centering" the tire, ADDING a little more air (you know, bring it up to between 45 & 60 PSI), and then letting it set-up overnight (or, longer). It was ready to go the next day AS FAR AS I WAS CONCERNED.

I have no doubt that mounting the clean tire on wet dabs of glue seems imprudent to some, but in reality there really is just glue enough to penetrate the tape's fibers ... and, undoubtedly any excess solvent wicks away over-night.

You may eventually conclude, as I did, that an inflated, UN-glued, new tire really doesn't want to go anywhere when it is mounted on a rim!

Inflate a new, unglued tire and see if you can roll it off the rim ... lean on the wheel at an angle that simulates you & your bike carving a turn, too. Let the air out and see how readily it pulls/rolls away ... OR, doesn't!

For me, it got to the point where the glue-up was mostly to keep the tire from torquing on the rim when accelerating/braking ... but, again, I wasn't racing.

If you get a flat while you are on a straight, the sew-up won't roll off the rim.

If you get a flat while you are on a curve AND are going at a speed where the tire might roll off if it weren't glued, it probably really isn't going to matter how much glue you have on the rim & tire. :eek:

TUFO makes a special double-sided tape which is apparently pressure activated ... apparently very easy to use, but much more expensive than a tube-of-glue. Good to go as soon as you inflate the tire.

FWIW. I am also under the impression that TOO MUCH glue can inhibit heat dissipation ...

alfeng said:

Regardless of WHICH instructions you follow, YOU MUST PRE-STRETCH A NEW TUBULAR TIRE (on an spare/old rim) otherwise there is no way on Earth that you will get a new tubular on the rim without making a mess of everything.

I recommend something closer to the second set of instructions ...

THE FOLLOWING IS ONE EXTREME GLUE-UP TECHNIQUE (and, not necessarily recommended):

When I used to use sew-ups (as recently as just a few years ago) I used the MINIMUM amount of glue you can imagine ... but, I wasn't racing.

After decades, it got to the point where I was basically putting a DAB between each spoke hole (36h wheel), and then rolling a NEW (as in clean) BARELY INFLATED pre-stretching tire onto a "clean" rim ... "centering" the tire, ADDING a little more air (you know, bring it up to between 45 & 60 PSI), and then letting it set-up overnight (or, longer). It was ready to go the next day AS FAR AS I WAS CONCERNED.

I have no doubt that mounting the clean tire on wet dabs of glue seems imprudent to some, but in reality there really is just glue enough to penetrate the tape's fibers ... and, undoubtedly any excess solvent wicks away over-night.

You may eventually conclude, as I did, that an inflated, UN-glued, new tire really doesn't want to go anywhere when it is mounted on a rim!

Inflate a new, unglued tire and see if you can roll it off the rim ... lean on the wheel at an angle that simulates you & your bike carving a turn, too. Let the air out and see how readily it pulls/rolls away ... OR, doesn't!

For me, it got to the point where the glue-up was mostly to keep the tire from torquing on the rim when accelerating/braking ... but, again, I wasn't racing.

If you get a flat while you are on a straight, the sew-up won't roll off the rim.

If you get a flat while you are on a curve AND are going at a speed where the tire might roll off if it weren't glued, it probably really isn't going to matter how much glue you have on the rim & tire. :eek:

TUFO makes a special double-sided tape which is apparently pressure activated ... apparently very easy to use, but much more expensive than a tube-of-glue. Good to go as soon as you inflate the tire.

FWIW. I am also under the impression that TOO MUCH glue can inhibit heat dissipation ...

Thanks. The stretching part I think I have down, it's the difference in gluing that has me confused.

mace112961 said:

Thanks. The stretching part I think I have down, it's the difference in gluing that has me confused.

I've seen tires where it is pretty obvious (?) that the person who glued up the tire used ONE TUBE PER TIRE. That is the other extreme.

A compromise would be a VERY THIN (as thin as possible) layer of glue on a clean rim surface. Let it become tacky. Add a DAB -- a DAB+ on a rim with fewer spoke holes -- and then, roll the new tire onto the rim ... et cetera.

If in doubt, try the minimal amount of glue that I use ... wait a day-or-two. Inflate the tires to 100+ PSI ... and then, try to manually pull the tire off the rim. Deflate the tire, and push the wheel laterally/sideways on a tightly woven carpet (this is to simulate a FLATED tire while going around a curve ... you could do it outside on cement-or-asphalt, but you would be really ticked at me if the tire came off the rim and the rim got scratched!) to see if it rolls off the rim ...

If the tire rolls off the rim :eek: ... re-glue the tire with more glue. REPEAT the process until the tire doesn't roll off during this static testing. That is about the only way that you will be satisfied that you have enough glue on the rim ...

OR, you could just go with the three-stage, tube-per-tire method!

BTW. As far as stretching, generally I only pull the new tire onto the rim AND I don't inflate it (other than to test it) ... so, it is not quite as stretched as if it were inflated.

After the tire has been inflated for a while, it won't be quite as tight ... NOT a problem.

The SPARE that you carry (yes, you should to carry at least one spare) should be pre-stretched.

It is probably BETTER to carry a new tire as a spare ...

The Tufo tape works very well, but it's a bit pricey at $5/tire. However, the cost of a tire popping off at the wrong time is considerably higher.

You must absolutely stretch the tires for at least a day before trying to mount them. When I bought a new set of tubies, at first I thought they had sent me 650's - no way these would fit. Took some work to get them onto a spare set of rims, but after sitting overnight, they mounted much more easily.

My test when I'm done is to deflate the tire, and try to roll it off the rim with my hand. It should resist a fairly firm pull.

One motivational trick I discovered by accident... I was in the process of cleaning a set of tubie rims and gluing on a new set of tires, and tossed on the 2003 TDF to watch while I was doing this. At one point, the stage comes on where Beloki skids in a turn, the rear tire pops off, and he gets slammed to the ground hard, breaking his hip and arm. I mean, he bounced when he hit the pavement.

After seeing that, I picked up the rims and started layering the glue on.

mace112961 said:

Okay,

So I'm thinking about taking my first attempt to mount my own tubulars. I come here and other boards and read a dozen "How to" posts. Most everyone agrees with the same basic method:
1. apply first coat let dry 24 hours,
2. apply second coat let dry 24 hours,
3. apply third coat and mount.

Several differing opinions on the best glue, but most everyone agrees Vittoria's Mastik One is a good choice.

I get a can of the glue and I'm ready to take on the project............. until I read the direction on the can!!! The directions totally conflict with the board advice:

1. Sandpaper rim (new or used) clean with solvent and leave to dry.
2. Clean the seam cover band of the tubulars slightly dipped in solvent
3. spread a thin layer of Mastic over the rim and over the seam cover
4. After 5-10 minutes maximum apply second coat of glue on rim only
5. Leave to dry for 3-5 minutes maximum
6. Mount the tubular on the rim, inflate slightly and center
7. Inflate to working pressure

Should I follow the directions of the board (presumably people that have done this lots of times) or the instructions from the company?

I'm open to any and all opinions and advice.

I have used both methods and they both work. Either way you should pump the tire to full pressure and allow the glue to cure overnight before you ride. Tufo tape can be ridden pretty much right away.

Personally, I think that the first method is better, albeit more time consuming. You can make things a bit easier by thinning the glue slightly with some lacquer thinner and brushing it on with a solvent resistant brush. The multiple coats makes up for the slightly thinner glue.