glue and tubulars

[spicoli]

Velonews has a good video link about a real basic no tricks or gimmicks way to glue up and prep tubs. Its worth a look if they still have it on there webpage. Basic and rock solid stuff.

[jimi]

Velonews has a good video link about a real basic no tricks or gimmicks way to glue up and prep tubs. Its worth a look if they still have it on there webpage. Basic and rock solid stuff.

http://velonews.com/article/74487

jimi

[dirt]

ahhhhhhhh!!!!!! my eyes!!!!!

hey how do I get anything besides the damn Trek ad?

Jason

[Too Tall]

Hey it happens. Popped a veloflex on my way home. Forced to run thru some glass, what yah gonna do? This is what happens and I hope it helps folks thinking about tubulars.

This is eactly what happened...I FREAKIN forgot my tools and pump ouch. Had to ride it flat for 5 miles to a local bike shop. Not really a big deal.

Once I sat down...three mins. later I had the flat off and the spare ,which is pre-smeared with glue and folded proper so that glue is against tyre surface not glue to glue was on and inflated :) Rode it home, cornerned with confidence...no psychotherapy required!

Once home I pulled out the big Velox repair kit and fixed the popped tubular...that process took 10 mins. Pic below is the tyre with 6 bars pressure.

Folks this ain't rocket science.

PS the bike shop wrench was grinning ear to ear he love it and said "kewl you even have a cool old leather toe strap that's sooooo cooool dewd". hehe another tubular tyre convert. :cheers:

[nicadog]

OK, so I have a problem that I could use some help with. I tried to glued up a Grifo 32s to brand new Velocity Escape rim.

Here were the steps I went through.

Lightly sanded rim
cleaned well with acetone
wiped clean with clean dry cloth
lightly filed grifo tape to remove any potential residual latex

put two coats of glue (masik one) on tire - let dry between coats

put two coats of glue on rim - let dry ( at least a day) between coats

Put another coat of glue on rim (not too thick - not too thin I thought), waited about 10 minutes and then put tire on. Adjusted centering where needed, inflated to 60 lbs, rolled tire on the floor and let sit overnight.

In the am, deflated tire and check for seal. It was terrible, some spots were OK but others just didn't take at all it seemed. I pulled the tire off the rim and the pictures below show what it looked like.

I've glued tires many times before using the same approach and never had a problem like this.

I'm open to any helpful suggestions you all might have - and going to clinchers isn't a helpfuls suggestion in this case - these are for 'cross and I couldn't imagine riding 'cross on clinchers.

Thanks a bunch.

[Too Tall]

How does the basetape look? Looks like all the glue pulled off the tape maybe.

[nicadog]

Some close ups

[Rico]

Looks like the rim wasn't complete clean and the glue released from it.
But just a guess.

[Roman]

Looks like the base tape absorbed a lot of the glue. I do what you do, plus tape.

[crumpton]

i will be shunned for this i am sure but 3x on the rim plus 2x on the tire and that rim pic sound and looks like too much cement leading to cohesion failure.

i am a single coat of panacement kinda guy. never lost a tire in 25 years. and i get a pair per tube of cement.

yes, too much cement can be bad.

[Winded]

By chance are you using Mastik 1 from the can? If so, how old and how much mixing before application? Seems like 11.4 mentioned some difficulty with cans - settling or something bad happens to the colloidal suspension. I believe he uses tubes of the stuff now. Of course I haven't quite ran out of my can of M1, so I just stir the heck out of it and of course test the bond as you did.
Just a thought.
ted.

[11.4]

Actually, on a Grifo cross tubular that really looks like one coat of glue with almost none coming up from the rim. I see one relatively smooth coat that isn't built up (which would happen with the second coat) and I see virtually no glue lumps or flakes that would be apparent if the glue had separated from the rim. On the rim itself, it looks like bare metal in the center but looks like the primary contact with the tire has been on the edges of the tire bed. The center of the bed is so clean it almost looks like glue was applied on the edges but not all the way across. Now this wouldn't necessarily have been a problem because this is how a fat cross tubular will sit on this rim anyway (and no amount of rolling the tire or other tricks will make the base tape stick there if there's a meaningful gap between rim and tire). And by the way, while the amount of glue might be less than ideal it should still stick well.

What I see here suggests that the glue job applied immediately before mounting the tire either was too thin or was allowed to dry too far. The rim and base tape basically look like the glue couldn't stick to itself -- basically no adhesion happened. I'd also suggest that the pressure while it was sitting overnight might not have been sufficient.

Your solution is pretty simple. I'd just apply another coat to the rim, thicker this time, and mount the tire promptly. If you want you can take a utility knife and run it along the edge of the tire bed on the rim to take off any excessive lumpiness there, but I don't see enough to worry about. Pump it up to more like 80-90 psi (a Grifo cross tubular will handle that easily) and let it sit overnight again. You should actually see a few little dots of glue ooze out around the crack between rim and tire (you can pull them off easily after the glue sets).

Now the one thing that isn't clear here, but possibly indicated, is that the tire doesn't match the tire bed sufficiently. I think you had a glue problem anyway, but you may have a problem with a fairly deep rim bed profile and a shallow profile fat cross tire. That tire barely sits on the edges of the rim bed with many tires, including Escapes. I've found that Ambrosio Nemesis rims have a really nice bed for cross tires, while the Escapes tend to be a little deeper and thus not as good a profile for the cross tires. You can make the Escapes work, but you don't have as much of a margin of safety. Any compromise in gluing can cost you in that instance.

Hope this helps.

[11.4]

By the way, because the problem of mismatched tire and rim profiles is so typical in cross, this is where using an adhesive rim tape (the stuff Thorne sells is particularly nice) in addition to the rim cement helps the gluing job quite a bit. Another idea for you. I don't like using the tape alone because it usually doesn't reach all the way to the edges of the rim, and it sometimes doesn't get enough pressure to be fully activated by the inflated tire.

[Too Tall]

Hi, thanks for the follow up pic. I'm piling on what 11.4 said. The glue on rim and tyre both look fine eg. they were applied and were still on there!!! Sooo, it's what 11.4 says...you waited too long. I've always applied the tyre while the glue on the rim was wet as in WET. Once you center the tyre and pump it hard once...deflate and press thru the tyre with your thumbs and reall mash the base tape into the bed than re-inflate to max psi overnight.

I use the tape sold by cyclocrossworld.com with glue per M.Z's recommend. That works.

[nicadog]

As always, a wonderful wealth of knowledge. Thanks everyone for the very helpful comments.

I think is was a combination of a number of things.

This was the bottom of can - and I did notice that as I dipped my brush in the bottom there was a sort of different milky (carmely?) look to the glue.
I was probably both too stingy on the application of the final coat, and too slow in putting the tire on.

So, here's my question, do I need to clean everything off now, or just put on another, generous, coat of glue.

Also, if I want to use the tape, do I put glue between the tape and tire, or just a generous layer of glue, tape and then the tire. I'm especially concerned about adhesion at the edges as these rims are a little narrow I think and I do like to run low pressures.


Thanks again!

[twowheels]

no need to remove the layers of glue. just put a good thick mounting layer on.

don't know about the tape.

[Too Tall]

You asked for it! Here is Mike Zanconoto's method for gluing cross tubulars.
I'd put one new thin layer on the rim than tape next comes the tyre with a fresh (wet) coat of glue. Mike and I differ. here but it amounts to same same..I'm old school and he's a young buck...when I install a tubular I like the tape surface to be dry so I can use my thumbs to get the last bit onto the rim...Mike has man hands and can yank the tyres on regardless of the resistance...a compliment 4 sure :) This is a good method. I've done this without tape and that seems fine too...the aquaseal is new to me and makes sense.
================================================== =====

Gluing Cross tubulars (Mike Zanconoto)

A lot of the basics of gluing a cross tubular is the same as a road tubular. But one particular contrast is tape alone, whether it's Tufo tape or Mastik tape, is a recipe for disaster. Especially in the wet of the Pacific Northwest. The constant mud and cleaning will render the tape useless. A top notch glue job will stand up to the constant exposure to water and mud. The edge bond is most critical but also the most vulnerable to cleaning and mud. The Tufo Extremee tape was mentioned, but the "Extreme" part of that product description means extreme heat. It is supposed to be used in hot weather, not cold and wet.

Mastik One is the best glue for the job. Personally, I use Mastik One glue combined with Mastik tape that you can get from cyclocrossworld.com. My process is pretty simple. First, be sure the base tape has no latex on it. On the FMBs, there has been some latex residue left from the "made by hand" process. I have never seen any latex on a Grifo before, but it can't hurt to double check. Clean the rim surface thoroughly with a solvent that does not leave a residue. Then I follow this procedure.
1. Stretch the tubular for a few days at 80 psi.
2. Remove the tubular for the first layer of glue. Pump up the to tubular a bit to give it some shape and so the base tape rolls out a bit.
3. First layer of glue on the base tape. Most base tapes suck up a lot of glue on the first layer. Let sit overnight.
4. First layer of glue on the rim. be sure to get all of the way to the edge. Let sit overnight.
5. The next day, deflate the tubular and give it a tug. The glue will shrink a bit as it cures.
6. Put the wheel in your stand and put another coat of glue on it. Follow it immediately with the tape. Leave the outer backing paper on the tape for the moment and then push the tape into the glue.
7. Put your second coat of glue on the tire.
8. Remove the backing paper. Cut a little hole in the tape for the valve stem.
9. Mount the tubular. I always mount the tires in the same direction front and rear. Just my preference. Put the valve stem in and then start stretching right from the start. It will get tough at the end. After you get it on, check that the base tape is roughly centered and try to correct any areas that are way off.
10. Pump the tubular up to about 35 psi and then give the wheel a spin. Check to see that the tread is centered. On hand made tubulars, the base tape and tread are not always centered. Try to correct it now.
11. Deflate the tubular and then use your thumb and press down hard on the tread to be sure the base tape makes contact with the rim channel. You want all of that gooey-ness underneath to make contact.
12. Pump uo to about 60 psi and let sit overnight.

**8 Aquaseal - for sealing sidewalls

[nicadog]

Thanks for the great suggestions. I'm going to try the glue/tape method and see how she goes. I'll report back to let you all know.
Cheers.

[Too Tall]

1 tube. Discuss.

[steve575]

I need your help. I’m a tubular rookie with problems. I’ve glued some cross tires in the past with great newbie luck, but I’m struggling with these Vittoria tires and Edge rims. There seems to be a slight mound of base tape around the valve stem that is keeping the tire from seating down on the rim. The tire rides a little high right at the valve stem, creating a slight gap between the tire and rim. It also causes a slight hump in the tire, making it out of round. The tires were glued when I bought the wheels, so I asked Too Tall for advice, and ended up pulling the tires and re-gluing. I thought I fixed the problem, but once I started riding them, I realized I had not.