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

cyclotoine 07-26-06 04:49 PM

there are lots of gommitlaia champion and clement futura (or something close to those names) comming up on ebay... They seen to sell pretty cheep. Are these low quality tubulars? What is the clement hierarchy?
thanks
anthony

USAZorro 07-26-06 08:05 PM

Clement Futurox - Not bad, but probably lower end. I've been riding some for the past year, and they've done reasonably well. I actually got some of mine because my LBS couldn't get me the Gommitalia's that a friend of mine recommended. Never rode them yet, so I can't give my first-hand impression.

godspiral 07-26-06 08:24 PM


Originally Posted by OLDYELLR
I just came across this in an archive. It sort of confirms what has been my gut feeling all along.

"I've seen enough tires that had been ridden
that had as good as no glue on them and they stayed on. The center of
pressure of a tubular at 45 degrees lean is still within the width of
the rim. That would be 0.707 of the distance between the central
plane of the tire and the cross sectional diameter. For a 22mm tire,
that's 7.777mm on a 20mm wide rim or 10-7.777=2.223mm inside the edge
of the rim. This is not a good practice without glue but it explains
why there it doesn't take a large disturbing load to roll the tire.

Jobst Brandt"

The very last sentence is contradictory to what leads upto it. Is there a typo in the last sentence? should it read
"... but it explains
why it does take a large disturbing load to roll the tire." ?

OLDYELLR 07-27-06 07:20 AM


Originally Posted by godspiral
The very last sentence is contradictory to what leads upto it. Is there a typo in the last sentence? should it read
"... but it explains
why it does take a large disturbing load to roll the tire." ?

I pasted the text directly from "Tubulars" here: http://yarchive.net/bike/index.html and you're right. But you do understand the principle; a large part of the cornering force is resolved intothe plane of the wheel, pressing the tire onto the rim, not tearing it off sideways. It's not as bad as it would be on a car wheel with no negative camber.

godspiral 07-27-06 12:01 PM

I ordered some tubulars and the velotec tape. I imagine the reason you got gunk around the edge of the tire is that it is too wide. I'll consider trimming the edges before applying.

mattmelcher 08-07-06 07:27 AM

I went 'old school' this weekend and it was quite interesting...

About 30 miles into my ride i noticed my rear tire was looking kinda low. Checked it out and discovered a slow leak from a puncture. Since I was going 'old school' I didn't have any spares, so I put some more air in the tire and went on for about a mile and checked it again. Needed more air so I figured I would have to stop every mile or so until I got back home. I was about 5 miles from nowhere when this happened. So on I went and all of the sudden 'PSSSSSSST'...The front tire was flat. It took about 10 seconds and that was it...I checked it out and it wouldn't hold any air...CRAP! I rode VERY SLOWLY (less than 5 miles an hour). For the next hour - stopping constantly to put air in the rear and walking whenever the road got rough. I Finally made it home and pulled the tires off. The rear tire is relatively new and I could easily find the leak; I'll fix that sometime in the near future. The front tire was a different story. I first put it on the rim about 12 years ago, and it hasn't been ridden for 10 years. I could barely get it off the rim. When I did, I found out the sewed up part was coming apart, and I had a pinch flat...I couldn't believe it. I also discoved the sidewall was falling appart. It's time for some new tires...I don't think I'll ride old shool next time...

godspiral 08-19-06 06:20 PM

Velotec tape was extremely easy to put on. Seemed to match the width of my rim exactly (20mm or so). Definitely something you can get right on your first try. Seemed a little tricky getting tire on exactly centered, but doesn't seem to be any riding impact.

caloso 08-23-06 01:06 PM

http://sacramento.craigslist.org/bik/197567536.html

$20 for a set of tubular wheels. I have no idea if these are any good, but a double sawbuck for anything is a deal these days.

bejay 08-24-06 02:17 PM

sealent, who makes the best one
 
hey did a search...but wondering if people's opinions have changed, so which is the best tubular sealant and how many psi can you use it up to before it begins to leak

thanks

j.

lotek 08-24-06 03:13 PM

I hear very good things about the Vittoria pit stop (or something like that).
Slime, Tufo, and Tube Spooge (rock n' roll) are all good to about 100psi
anything higher than that will leak (or spew all over you). Of course
depends on size of cut/puncture, I would imagine that wire (from
auto belted tires) at about the size of a staple would seal effectively
to higher psi than small cut.

Marty

peripatetic 08-24-06 11:52 PM


Originally Posted by godspiral
The very last sentence is contradictory to what leads upto it. Is there a typo in the last sentence? should it read
"... but it explains
why it does take a large disturbing load to roll the tire." ?

Just about every linked post I've read by Jobst Brandt was contradictory in some way. For being such a conceited, prickly know-it-all, his writing borders on remedial. I've read, re-read and re-read again his quoted post on Sheldon Brown's site about tire sizes, and I have yet to parse out the exact reason for different tire sizes, even though the final line is something like, "So you see, there is a good reason tires have changed in size." I find his writing obtuse, inconsistent and generally irksome. If only one of those posters on rec.bicycles.net would actually point this out to him, instead of arguing with some point he's made in one of his impenetrable posts: his vagueness serves his purpose, and he often responds to people with "No, what I said was..."

USAZorro 08-25-06 07:18 AM


Originally Posted by peripatetic
Just about every linked post I've read by Jobst Brandt was contradictory in some way. For being such a conceited, prickly know-it-all, his writing borders on remedial. I've read, re-read and re-read again his quoted post on Sheldon Brown's site about tire sizes, and I have yet to parse out the exact reason for different tire sizes, even though the final line is something like, "So you see, there is a good reason tires have changed in size." I find his writing obtuse, inconsistent and generally irksome. If only one of those posters on rec.bicycles.net would actually point this out to him, instead of arguing with some point he's made in one of his impenetrable posts: his vagueness serves his purpose, and he often responds to people with "No, what I said was..."

Agreed. I don't understand why he has the reputation of being an expert. He does not come off as articulate - at least not in English.

peripatetic 08-25-06 09:19 PM

Just curious: any company manufacture a tubular snow tire, say with studs?

Second, I just did a quick browse of Biketiresdirect.com; do the Conti Gatorskins only come in 22c widths, or can one get them wider?

intron 12-27-06 05:17 PM

who makes some tubulars that are pretty good against flats? i don't think im ready to be unstitching and sewing up casings. so, a tire that will keep that to a minimum would be nice. the rims are Mavic GP4

el twe 12-27-06 05:23 PM

Maybe Tufo? Plus, they make that sealant stuff.

onetwentyeight 12-27-06 08:54 PM

continental makes gatorskin tubulars now. i am a fan.

intron 12-27-06 11:12 PM


Originally Posted by onetwentyeight
continental makes gatorskin tubulars now. i am a fan.

i run gatorskin clinchers, and i love them, where is the cheapest place to get the tubular version?:D

el twe 12-28-06 09:59 PM


Originally Posted by onetwentyeight
continental makes gatorskin tubulars now. i am a fan.

I gotta say, I'm pretty excited for these.

vxpro 12-29-06 01:53 PM


Originally Posted by intron
i run gatorskin clinchers, and i love them, where is the cheapest place to get the tubular version?:D

$44.95 from biketiresdirect.com was the best price I found but didn't search very hard.

onetwentyeight 12-29-06 02:37 PM

i got mine from bike tires direct, too.

sbarner 12-30-06 12:44 PM


Originally Posted by USAZorro
Here are a few things I've learned about preparing tubulars for installation in the past 6-7 months.

When you get them, inflate them to about 40 psi - don't mount them on anything yet.

After a few days (maybe a week), deflate, and mount them on a rim (no glue), and inflate to about 40 psi again.

I don't like inflating sewups when they are not mounted. They have a tendency to try to turn inside out and this stresses the glue joint between the basetape and the casing. I just mount them on a junk rim or spare wheel and inflate to full pressure. I leave them that way until I am ready to use them. Don't mount sewups on unlaced rims that you plan to use someday.

Originally Posted by USAZorro
Also, a few days before you want to glue them on, put a layer of adhesive onto the rim(s) you're going to mount the tire(s) to.

Unless you're dealing with really old tubulars, I suggest using 3-M Fast Tack for glue. I must say though that I've heard that Fast-Tack can cause the base tape on older tubulars to separate from the tires. I had a pair of old Wolbers that this happened with, but I haven't had it happen on any of the other tires I've used. Anyhow, here's a technique that I've used to mount tires with very little mess. I don't ride very aggressively, so I haven't ridden on any hairy, high-speed descents, so I can't vouch for how this holds under those conditions.

Lots of people use Fast Tack for sewups but I stay away from it. It holds a bit too well, if that can be possible, sometimes stripping the basetape off the tire on removal. Its biggest problem is lack of residual glue to grip a spare installed on the road. An advantage is it sets up really quick, making an unexpected flat change before a ride possible. It's also cheaper than real tubular cement, which is probably the biggest reason why racers use it.

Originally Posted by USAZorro
Before you start, have some mineral spirits and a clean cloth rag at hand. Sit in a plastic chair in a clean well ventilated space, and put on vinyl or latex gloves - the very thin ones. Deflate the tire, put the stem of the tire into the hole in the rim. Make sure you have the tire oriented the way you want it. Once the tire is on the rim, sit in the chair, hold the rim with the stem up. Grasp the tire about one spoke hole away from the stem and lift it up. Squeeze a bit of glue onto the exposed sections of the rim. Move the glue tube around to get a light coating on the entire surface. Release the tire, being certain that the base tape is centered, rotate the rim two spoke holes, and repeat the process. Do this until you make it back to the stem.

If you get any glue on the tire, rim, spokes or yourself, wipe it off immediately. Use mineral spirits as necessary to clean the glue from any metal that it gets on.

I used to do it this way. It's cleaner and it might work ok if you preglue as you recommended earlier. However, it's really important to preglue the basetape as well as the rim. Manufacturers recommend three coats of glue. I preglue the rim and basetape, let them both dry (this happens pretty fast, if you are in a hurry), then add another coat to the rim just before stretching the tire on. If the tire is prestretched and you are careful, this can be done with minimal mess. After 12 hours, the bond I get with Continental cement (which I buy in cans) grips like a vice. I have strong hands, but I need a key or tire iron to start working a flat tire back off the rim. Roughing up a new rim with sandpaper is also important. It's not a godd idea to use mineral spirits on a tire, as it can create problems if it gets to the tube.

Originally Posted by USAZorro
Once you've completed the gluing, inflate to about 25 psi. If any glue oozes onto the tire or rim, wipe it off immediately. Also make any manipulations you may want to center the tire if it hasn't gone on quite as straight as you want. You may need to decrease the pressure in the tire to do this. After 30 minutes, inflate the tire to about 40 psi and let the rim sit over night. I've had no problems riding on the tires the next day.

I totally agree.

el twe 02-26-07 05:03 PM

I'm in the process of gluing my first set of tubulars, and have a quick question: is it a problem to leave some of the old glue on the rim? I scraped and mineral spirited what I could, and I may be able to get some more off, but if I don't have to I'd rather not.

DiabloScott 02-26-07 05:07 PM


Originally Posted by el twe
I'm in the process of gluing my first set of tubulars, and have a quick question: is it a problem to leave some of the old glue on the rim? I scraped and mineral spirited what I could, and I may be able to get some more off, but if I don't have to I'd rather not.

If it's that hard to get off, it'll be a great surface for the new glue to bond to. Don't take it off unless there's so much that it gets in the way or spills over the edge.

el twe 02-26-07 05:12 PM

OK, that's sort of what I figured. Thanks for the help.

San Rensho 02-26-07 07:48 PM

Try putting masking tape on the braking surfaces of the rim. Makes clean up much easier.

el twe 02-26-07 07:52 PM

I read that, thought, "Hmm, that's a really good idea," and then proceeded to not do that. Maybe on the next one...

el twe 02-26-07 08:11 PM

OK, just got the rear done. My hands are covered in Tubasti. Can I use mineral spirits to get glue off of the tire itself? How terrible is it to have the valve stem angled (not perpendicular to the rim)?

CV-6 02-26-07 09:18 PM


Originally Posted by el twe
OK, just got the rear done. My hands are covered in Tubasti. Can I use mineral spirits to get glue off of the tire itself? How terrible is it to have the valve stem angled (not perpendicular to the rim)?

If it is not perpindicular, you are asking for a failure at that point. Mineral spirits are not recommended for use on the tire.

el twe 02-26-07 10:32 PM

Tire cleaning is gonna be fun - shoulda worn gloves.. The valve isn't actually not terribly off-center, so I'm just gonna leave it for now.

lotek 02-27-07 08:33 AM

el twe,

If you have tubasti all over the place you are working with glue that is too wet.
Let it dry a bit before mounting the tire. It should be tacky, not runny.
and you might be using too much glue!

marty


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