Mounting new tubular - is this normal?

[weisan]

I just installed a brand Vittoria Elite tubular, noticed the basetape sort of extend outside of the rim bed on one side, is that normal?

[denapista]

uhm..... You should take that tire off and center it... That's the irritating process of mounting tubular tires.. once you get the tire on, you have some time to center it and get any wobbles out of it. There should not be that much basetape showing on one side.

[weisan]

I did but when I inflate it, it wants to go back to the original state.

The basetape is definitely much wider than the rim profile. Either way, it's going to show on either or both sides.

[teleguy57]

In general, you should see a similar amount of basetape on each side of the rim; that's normal. However, what's most important is that the tire runs true when you spin the wheel in your hands and sight down the tire. You don't want to see side-to-side wobbles.

Occasionally you'll end up with base tape not quite the same on each side, but if the tire runs true that's ok.

[Neil]

I'd pull that tub off and go again, looks like the valve is catching on something as it's pushing the tyre off the rim/not allowing it to seat correctly.

[weisan]

I have pulled the tub off and re-mount for like three times already.

No, there's nothing obstructing the valve, it was like that from the beginning even when the rim is brand new, clean and free of glue.

In its current form with the basetape showing more on one side, it doesn't wobble side to side.

[Hindmost]

Is the tread centered?

[FlashUNC]

How's the tread look when you spin the wheel and eyeball it? It got a side-to-side wobble like a Hot Wheels race track? Or it straight?

[fuzzalow]

No. Do not center the tire on the rim by centering the basetape on the rim. You cannot be assured that the basetape is perfectly centered along the rolling axis of the tire carcass. As such you never center using the base to show equal amounts of tape along the edge of the tubular rim.

Center the tire using the carcass of the tire to be centrally mounted on the rim. The center section of the tire is mounted so when you spin the wheel the carcass does not wobble to and fro on the rim. You do not twist the carcass of the tire to follow and trace the path of how the basetape is manufactured to the tire. It is rare that basetape be perfectly centered - but the tire carcass should be straight and that is the important thing.

I can always give you the long answer.

[buldogge]

I think glue might change this equation...slightly. ;)

-Mark in St. Louis

I did but when I inflate it, it wants to go back to the original state.

The basetape is definitely much wider than the rim profile. Either way, it's going to show on either or both sides.

[echappist]

No. Do not center the tire on the rim by centering the basetape on the rim. You cannot be assured that the basetape is perfectly centered along the rolling axis of the tire carcass. As such you never center using the base to show equal amounts of tape along the edge of the tubular rim.

Center the tire using the carcass of the tire to be centrally mounted on the rim. The center section of the tire is mounted so when you spin the wheel the carcass does not wobble to and fro on the rim. You do not twist the carcass of the tire to follow and trace the path of how the basetape is manufactured to the tire. It is rare that basetape be perfectly centered - but the tire carcass should be straight and that is the important thing.

I can always give you the long answer.
and just how do we go about doing the latter?

[etu]

Weisan-pal,
I am a relative newb, but here's what I have learned on the 4 or sets of tubulars that I've mounted. Hopefully the experts will chime in if I am saying something wrong.
1) I've found that you shouldn't wait too long after putting on the last layer of glue. In fact, I start mounting as soon I am done so that I have more time to wiggle the tire around when the glue hasn't set yet.
2) Inflating the tire seems to help center the tire. You don't need to get it up to 100 psi, but enough so the tire is firm. Irregularities that seemed to be a problem with the tire uninflated seems to work themselves out.
I am still figuring out how to seat the area around the valve better, but based on your picture, there is definitely a problem.
Don't give up!

[ultraman6970]

I had this before, is the tubular that is twisted from factory. You have to turn it by hand a little bit to be able to get a better fit (dont sweat it because you wont be able to get it perfect ok?). It is usable just in case, hope you dont have a bump that is too big too.

To be honest, Vittorias arent the more straight tubulars in the market.

[11.4]

Good grief, people. What's with the advice here?

Wesson, your valve stem can only go into the hole in one way, and that's the area you're photographing with a base tape problem. You can't change the position of the valve stem so if the base tape is misaligned there, you'll just have to live with it. It's not uncommon that the base tape is out of position, especially near the valve stem. When you mount the tire, aim for the carcass of the tire to be centered and the centerline of the tread to make more or less a straight line. The tire can either be off center in a section because you mounted it off center, or it can be twisted on its axis (rotated over a short section while on the rim) by putting it on with an off-center section and then rolling the tire to get it in place. That centers the tire but it's twisted in that area, leading to tire problems, higher rolling resistance, a potential bump, and poor gluing there.

When you put the tire on, sight down on the tire with about 20 psi in the tire. If you are off-center on the rim bed, you'll see it at the bed and also sighting down the top of the tire as you spin the wheel in your hand. Now here's the important thing: Don't twist or rotate the tire to move it into position. Pull it up, move it sideways until it's centered, and then put it down -- in short, don't rotate, just lift and pull sideways. That keeps you from all kinds of new problems.

Your tire seems to have a bit of a bump going on there too, caused by the valve stem not seating all the way into the hole. The base tape may have a little wrinkle or bump there, or the fabric of the casing itself, or the flange of the valve stem may not have been aligned quite right. Sometimes these issues sort themselves out after you've ridden the wheel a couple rides. If they don't you can either live with it or pull the tire and fix it. Don't worry if it looks weird from the side. If there's no bump in the tread (as in, narrowing the gap under the fork crown or seat stay bridge) you should just live with it and write it up as a not particularly nicely made tire. If there's a bump, you'll probably feel it and not like it after a while, and if it compromises tire clearance it's a must-do repair. Taking the tire off, you may be able to trim some of the base tape or other fabric piled up around the valve stem with a sharp blade. Obviously, don't cut anywhere near the inner tube. Try it on the rim and see if that works. You may have a rim (and there are some) that have a tight rim bed and minimal valve stem hole so they always make tires sit high. If that happens with this and other tires as well, one option is to take a reamer and chamfer the valve hole a little, creating a little more room for remaining fabric. Do this cautiously and with some hesitation, because modern rims tend not to need this fix as often. One rim that often does give problems is the Ambrosio Nemesis -- the metal fitting at the valve stem is slightly tight for many valve stems so they don't go all the way through. That particular case needs a small rattail file or a small chainsaw sharpening file to clean out any burs that prevent the valve stem from seating fully. Don't worry about this if your tire tread doesn't have any kind of bump or twist.

One last point. Always mount tubulars on a dry clean rim before you start gluing. If you get a funky tire, and this looks like it's close to qualifying, take it back and get a replacement. Sometimes it's the really high-end tires that have the most problems like this, and I've returned a lot of FMBs and Dugasts for problems like this. The minute glue touches the tire, you can't return it. It's always an important step to do quality control before you start gluing.

You did everything right here. These were just a few tricks that you learn with a lot of tubulars.

[buldogge]

Ummm...Look at the basetape..There's no glue on it (basically). :confused:

Weisan, are we talking about a dry fit, here?

You need to coat the base tape, as well as the rim...you need to pay particular attention to setting the stem area, and then you need to move out and around from the stem, following 11.4s advice!

-Mark

[elcolombiano]

No. Do not center the tire on the rim by centering the basetape on the rim. You cannot be assured that the basetape is perfectly centered along the rolling axis of the tire carcass. As such you never center using the base to show equal amounts of tape along the edge of the tubular rim.

Center the tire using the carcass of the tire to be centrally mounted on the rim. The center section of the tire is mounted so when you spin the wheel the carcass does not wobble to and fro on the rim. You do not twist the carcass of the tire to follow and trace the path of how the basetape is manufactured to the tire. It is rare that basetape be perfectly centered - but the tire carcass should be straight and that is the important thing.

I can always give you the long answer.

The tape is not always placed exactly in the center. What is most important is that the tire is centered, not the tape.

[oldpotatoe]

I just installed a brand Vittoria Elite tubular, noticed the basetape sort of extend outside of the rim bed on one side, is that normal?

Not centered, as I mentioned, take the tire off the rim and inflate. See it turn 90 degrees? Before the glue is sticking, the same thing will happen on the rim..center it with just a little air, roll on ground, let sit.

[weisan]

Thank you thank you all my pals, especially fuzz and 22.8/4 pal who took the time to write such a clear and thorough explanation/instruction.

Not very good pictures but hopefully you can see the bulge around the valve stem, lifting the base tape above the rim bed and won't let the adhesive do its trick. It's also causing a hop. I have "enlarged" the valve hole on the rim slightly but that still doesn't fix the problem. I am a bit leery about performing surgical changes to the base of the valve stem itself. I can use the big chopper knife pretty good but when it comes to the needle and thread stuff, I am hopeless.

[weisan]

Not centered, as I mentioned, take the tire off the rim and inflate. See it turn 90 degrees? Before the glue is sticking, the same thing will happen on the rim..center it with just a little air, roll on ground, let sit.

I did!

[11.4]

A spot like that around the valve stem will typically do one of two things. Assuming a good coat of glue on it, a few miles on the road will either settle the valve stem in properly or at least adhere the glue solidly, or else it will pop up and down with every wheel revolution and you'll hear this little popping or squeaking sound as the glue gets pushed together and then pulls apart again.

As far as risk, the valve stem is the last place where the tire will want to roll, so this isn't about keeping the tire from coming off the rim. It's about avoiding a bump in the tire and excessive flexing and noise at the glue joint.

It's pretty clear there's too much base tape right there (which actually means there's probably some casing fabric in the way underneath, and the process of sewing the casing in around the valve stem was done badly). Live with it if it feels and sounds acceptable to you, or pull the tire and shave off some of that extra fabric. You do want fabric around the valve stem, so don't take it all the way down to the stitching -- that's a high wear area because the valve stem wants to flex with every wheel rotation. Note that the tire casing looks a bit narrowed at the valve stem as well. That's basically an effed up assembly on that tire at the factory. If you got the tire at a local shop or at a mail order shop you can talk to and have a good relationship with, see about replacing the tire. This isn't how you should start learning about tubulars.

[moobikes]

Is the valve actually in the middle of the base tape?
Is the base tape in fact off center?

I see about equal amounts of sidewall exposed from base tape to tread, on both sides of the tire.
If it is in fact off center then you have no choice but to use it that way.
The double layer of base tape around the valve, nothing to be done. Every tubular is like that.

You can also bias the tape a bit to the other side as you glue it down. So the casing twist will cancel out your bias and straighten the tire out on the rim.

The small bulge or hop in the casing around the valve, this step is how to get rid of it -->

You have to stretch the tubular a little as you mount it. Just a little bit, hands on both sides of the valve, and press it down as you move along to the next part of the tire/ rim. Just enough stretching to even out the casing around the valve so that there is minimal or no hop. Stretch the tire less as go along especially if it's a cotton tire. Stretching helps the reduce the casing twist also.

Some tubulars have twists that are hard to undo and will lean to one side of the rim, even with a good glue job. It's not a huge deal but looks odd especially if it's the front wheel.

[weisan]

I have tried drilling the valve hole a bit bigger but that doesn't resolve the problem. There's simply too much material at the base of the valve stem so much that it's causing the carcass of the tire to twist unnaturally to one side. You can see from the pictures...thanks pals for chiming in, I really appreciate it.

[oldpotatoe]

I have tried drilling the valve hole a bit bigger but that doesn't resolve the problem. There's simply too much material at the base of the valve stem so much that it's causing the carcass of the tire to twist unnaturally to one side. You can see from the pictures...thanks pals for chiming in, I really appreciate it.

Sumethin wrong with that tire...twisted at valve or something. Refund!!

https://www.youtube.com/watch?v=fQaavQNGsMY

[11.4]

I agree. That vertical shot is telling. The tire isn't sitting straight and won't. That should be replaced. And because it's at the valve stem, where it can never be straightened, you have a fair chance of getting a replacement tire.

[FlashUNC]

Odin's Beard, thats a wobble.

[11.4]

I doubt you destroyed it, but I wouldn't have drilled out the valve stem hole. You might include a photo of what you did when you take the tire off. And I would take that tire off and get an exchange. It'll never ride right and will fail early.

[weisan]

Thank you 十一点四朋友.

[weisan]

Pictures of another tubular on the same wheel.

[11.4]

Much better. There's a slight bump in the base tape at the valve stem, and it might translate into a bump at the tread. But this is within the tolerances of a decent tire.

[ultraman6970]

Weisan in case you are anal for perfection ok? Tubulars in general are never perfect so have that in mind, you can twist the tubulars up to some extend but the previous one was just insane bad, I had tubulars like that before and I used them as spares.

Never expect perfection and learn to live with those little things here and there, it is what it is.

Hope you can return the other one but since is glued already who knows if they will take it back.

[malcolm]

From 11.4

Don't twist or rotate the tire to move it into position. Pull it up, move it sideways until it's centered, and then put it down -- in short, don't rotate, just lift and pull sideways. That keeps you from all kinds of new problems.

I don't ride tubbies anymore but this is the biggest mistake I see newbies make. Never ever twist or rotate to center, lift and then move to one side or the other.