How To: Gluing CX Tubulars / Not tonight honey, I've got a Mastik 1 headache

[zank]

Used this guide last year with excellent results, so thanks mike! Question: looking at gluing a fresh set of tires to a previously glued wheelset. Last year's Belgian tape looks to be in decent shape and I'm not sure whether I can apply a fresh coat on top and a few on the tires or to remove the tape and start over again. Thoughts?

My pleasure! I'm with Josh on this. I would keep going with the base of glue and tape that's already on the rim. I would do two coats max on the tires. On the rim, I would do a light coat to freshen up the surface and then do the mounting coat.

[Too Tall]

I recently had this experience with a Vittoria XM and it took a lot more than "a few times" of snapping to get it straight. I finally threw it lightly inflated in the back of my car in the sun on a hot day and warmed it up for an hour then snapped and re-stretched- problem solved. 'Course this method requires a bit of summer, so you're hosed once the season starts...

You must have a perfectly good cloths dryer? (running for cover)

[ineff]

I agreed with almost all that people have said here.

Two things though...

1) I don't use tape. Never found it to be necessary. I seem to have god luck with a muti day glue process without tape.

2) I strongly recommend NOT airing your tires to pressure. This can pull the center of the tire away from the rim depending on your rim/tire combo. I actually leave tires completely deflated after I have centered them, etc.

[s_curran]

Ok, half way through my first try. I had got some basically free wheels, and had picked up some used Zank Griffos from a swap. So really I barely have 100 bucks committed to this. I cleaned the rims all the way to new, I had no idea what glue was on them, but it was bad.

My question comes to the tires, the basetape had glue on them, and they seemed to be separating from the tire in places. I already put glue on them, and tried to over saturate those areas and smosh it together. It still looks pretty rough, and it seems as though one of the tires has a ton of extra base tape in a way. I'm sure I should have just paid to have them re-taped, but I didnt. Are they going to work ok? To be honest I doubt the rims will even hold me for long (velomax orions). Is this going to end terribly? stick with my clinchers for the season?

[Too Tall]

Would you pls post a few pics of the basetape glue job? Make sure we can see the "bad" sections edgewise

[s_curran]

Attachment 72537Attachment 72538Attachment 72539

These are the worst areas.image.jpg

[Britishbane]

Attachment 72537Attachment 72538Attachment 72539

These are the worst areas.image.jpg

Those look like a no-go to me.

[Too Tall]

What he said. The over application of glue most probably is responsible for separation of basetape from the tire carcass. Specifically, when you apply alot of glue all at once the massive amt. of solvent overwhelms the basetape to tire bond and you can see separation like what you have shown us.

Regardless, you have two options. Send it to tirealert for new basetape or yank up all the loose portions of basetape, careful not to tear and reattach using latex adhesive. Carpet cement is pretty easy to come by from hardware stores and will do in a pinch. Don't use tubular tire cement, that's not the right stuff.

The process for re-attaching is not hard. Laydown a couple layers of latex on the tire and on the basetape separately and let each application dry to the touch than inflate to 3/4 psi and wrap the tire with plastic wrap and blue painters tape over the areas that need work and now inflate to about 8/9 psi and leave it for 12 hrs. That *should* do the trick. You be the judge.

What you posted a pic. of will kill you if you just glue it up and ride.

[s_curran]

What he said. The over application of glue most probably is responsible for separation of basetape from the tire carcass. Specifically, when you apply alot of glue all at once the massive amt. of solvent overwhelms the basetape to tire bond and you can see separation like what you have shown us.

Regardless, you have two options. Send it to tirealert for new basetape or yank up all the loose portions of basetape, careful not to tear and reattach using latex adhesive. Carpet cement is pretty easy to come by from hardware stores and will do in a pinch. Don't use tubular tire cement, that's not the right stuff.

The process for re-attaching is not hard. Laydown a couple layers of latex on the tire and on the basetape separately and let each application dry to the touch than inflate to 3/4 psi and wrap the tire with plastic wrap and blue painters tape over the areas that need work and now inflate to about 8/9 psi and leave it for 12 hrs. That *should* do the trick. You be the judge.

What you posted a pic. of will kill you if you just glue it up and ride.

Ok, thanks. This is what I figured I suppose.

There is also a section that is slightly torn, so I'm thinking they just go to tire alert. Maybe in the meantime I'll try and find myself a slightly nicer set of wheels...

[Too Tall]

Good call.

[ericpmoss]

This is carbon-specific (?), not cx-specific, but I didn't see an answer elsewhere...

The instructions on Mastik 1 say to let one layer dry on the tire and rim, and then put one layer on the rim and mount the tire immediately.
The instructions on Conti Carbon-specific glue says to let one layer dry on each, then put one layer on the *tire*, NOT the rim, and mount immediately.

Conti says put the last layer on the tire "because you want it to soak into the cotton casing a little bit." I assume they mean base tape, but it still makes no sense to me. Any ideas why the difference, e.g. to soften a hard-to-stretch Conti tire a bit more?

[dashDustin]

Are you stuck using the carbon specific glue, or can you get the normal stuff?

I know it doesn't answer your question, it's just....that carbon-specific glue....meh....

[Too Tall]

If you have not previously prepped the basetape with glue sufficient to occlude further saturation of said basetape all hope is lost. Politely backing away from their advice yo. My concern has to do with oversaturation of basetape possibly resulting solvent reaching basetape glue compromising the basetape to tire carcass bond...you go boom on your arse ASAP if that happens.

Use multiple (two is good) THIN (as in sparse scrubbed in with a clean toothbrush) layers on uncoated basetape (Conti. is uncoated, Vittoria is coated) drying between coats. Two coats on the rim using "enough" edge to edge, drying between coats (two coats is enough). NOW you have options...you can put a last coat on the tire and mount immediately OR you can put a heavy coat on the rim and mount immediately. It is you call pal. Personally, I like to have a dry coat on the tire so that I can manhandle it onto the rim. If the tire has wet glue it is orders of magnitude harder to install the tire...unless it is a Vittoria and in that case does not matter 'cause they go on so flippin' easy.

Bruddahs don't let bruddahs ride gawdawul stinkin' clinchers.

[ericpmoss]

Are you stuck using the carbon specific glue, or can you get the normal stuff?

I know it doesn't answer your question, it's just....that carbon-specific glue....meh....

At some point I bought a few different kinds on sale -- Conti, Vittoria, tube, can, carbon-specific, etc. I'm getting toward the bottom of a can of Mastik One, so it's time to get up to speed on what's left.

I'll try TooTall's recommendation from the immediately previous post, as it is known to work, and I can't find a good explanation of the "must put final layer of Conti Carbon glue *only* on the tire" approach. Once the Conti glue is gone, I'll likely go to Mastik One in tubes.

[dashDustin]

I've heard bad stories from mechanics using methods other than what Conti says for the carbon specific glue. I couldn't trust it. Hate saying it, but might be worthwhile calling Conti and asking them. I assume their instructions are referring to their tires.

[dashDustin]

Chip Howat, a professor at the University of Kansas, is the foremost expert on tubular gluing and adhesion. He has literally written the book on proper installation techniques and ranked the performance of the bike industry’s tubular adhesives. We were the first to talk to Howat about Continental’s new glue, which after testing he recommends for use with carbon tubular rims.

“It did well,” said Howat. “I did four separate tests: one with [Vittoria] Mastik One, one with conventional Continental glue, one with the carbon glue following the manufacturer's recommendations and then one using the carbon glue and my procedure [three light layers of glue on the rim, one on the tire]. Using my gluing procedure against the standard [Continental] glue, it looks like 20 to 25 percent better. [With their procedure] it’s still good, better than conventional, but only marginally so.” Howat hasn't yet tested the new glue’s heat resistance.

Howat’s method for gluing is a process that one of his students earned his master’s degree testing. “We tested every procedure that we knew was out there and then developed our own,” said Howat. “We found that multiple layers on the tire — now these were all conventional glues, before the carbon glue came out — didn’t make a difference; one coat was sufficient. What really made a difference are multiple coats on the rim. We tested one coat, two coats, three coats, four and five coats, and we found that diminishing returns set in after three coats."

from BikeRadar

that all said, i prefer a dry tire when mounting.

[Bobonli]

If there is a guy who is professor of tubular gluing, then TT must be Dean of Chain Lube.

[ericpmoss]

Much thanks to everyone -- I followed TT's version of the method and had my best ride ever -- absolutely solid ascending, descending and cornering, no squirm, and snappier acceleration. I also increased my spoke tension a bit (both wheels were true and had balanced tension, but on the low end of what Enve recommended; now they are in the upper end of the range). So that may have helped, too, but the difference with a solid glue job is dramatic. Well-done tubulars are pretty magical.

Yay! One question remaining, though: when a tire's cross-section radius doesn't match that of the rim, what's the rule? Do I try to make the final layer of glue thin and force the tire to match the rim even though it deforms the casing, or do I use a lot of glue to fill the gaps so the tire cross section remains circular?

[Too Tall]

Eric, i just build up a few layers of glue.

[ericpmoss]

Eric, i just build up a few layers of glue.

I don't quite follow, but based on the results of my different approaches on the front and rear, I'll first attempt to get the best fitting tire. Whatever the success of that, I'll use plenty of glue on the final mounting layer, and after centering, pump it up hard, letting the air pressure squeeze out any that doesn't fit.

Thanks again -- I'm really enjoying how the bike rides now!